NCERT - PLANT KINGDOM

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Questions and Answers

Which of the following is a method of reproduction in algae?

Budding

Fragmentation (correct)

Binary fission

Conjugation

All algal species are exclusively aquatic organisms.

False

Name one type of chemical information used in chemotaxonomy.

Chemical constituents

The term for the fusion of two dissimilar gametes in algae, such as Eudorina, is called __________.

anisogamous Signup and view all the answers

Match the following algal terms with their descriptions:

Isogamous = Fusion of gametes that are similar in size Oogamous = Fusion of a large non-motile female and a smaller motile male gamete Zoospores = Flagellated spores that are motile Filamentous forms = Algae that grow in long strands or threads Signup and view all the answers

What is a primary characteristic of algae?

They are autotrophic. Signup and view all the answers

Cytotaxonomy relies on the behavioral characteristics of organisms.

False Signup and view all the answers

What role do algae play in carbon dioxide fixation?

They carry out photosynthesis, contributing to carbon dioxide fixation. Signup and view all the answers

What is the primary role of marine algae in aquatic ecosystems?

Primary producers Signup and view all the answers

All species of marine algae produce significant amounts of hydrocolloids.

False Signup and view all the answers

Name two examples of green algae.

Chlamydomonas, Volvox Signup and view all the answers

The storage bodies located in the chloroplasts of green algae are known as _______.

pyrenoids Signup and view all the answers

Match the following classes of algae with their characteristics:

Chlorophyceae = Green algae with chlorophyll a and b Phaeophyceae = Brown algae with fucoxanthin pigment Rhodophyceae = Red algae commonly used for carrageenan Signup and view all the answers

Which of the following is a unicellular alga rich in proteins, often used as a dietary supplement?

Chlorella Signup and view all the answers

The cell walls of green algae consist of only cellulose.

False Signup and view all the answers

What type of reproduction is common in green algae?

Fragmentation or formation of spores Signup and view all the answers

Which of the following characteristics is shared by Chlorophyceae and Phaeophyceae?

They both reproduce asexually by non-motile spores. Signup and view all the answers

All algae reproduce exclusively sexually.

False Signup and view all the answers

What type of reproduction do Rhodophyceae undergo?

Oogamous sexual reproduction Signup and view all the answers

The major stored food in Phaeophyceae includes __________.

mannitol and laminarin Signup and view all the answers

Which pigment is primarily found in Rhodophyceae?

Chlorophyll a, d, phycoerythrin Signup and view all the answers

What is the habitat of Chlorophyceae?

Fresh water, brackish water, and salt water Signup and view all the answers

Match the following classes of algae with their corresponding characteristics:

Chlorophyceae = Green algae with chlorophyll a, b Phaeophyceae = Brown algae with chlorophyll a, c, fucoxanthin Rhodophyceae = Red algae with chlorophyll a, d, phycoerythrin Bryophytes = Mosses and liverworts found in moist shaded areas Signup and view all the answers

Polysiphonia and Porphyra are examples of __________ algae.

red Signup and view all the answers

What are the male and female sex organs called in gametophytes?

Antheridia and Archegonia Signup and view all the answers

All gymnosperms have their ovules enclosed by an ovary wall.

False Signup and view all the answers

Name one genus of pteridophytes that is heterosporous.

Selaginella Signup and view all the answers

The formation of the zygote occurs when the male gamete fuses with the _______ present in the archegonium.

egg Signup and view all the answers

Match the following classes of pteridophytes with their examples:

Psilopsida = Psilotum Lycopsida = Selaginella Sphenopsida = Equisetum Pteropsida = Dryopteris Signup and view all the answers

Which of the following features make gymnosperms well-adapted to withstand extreme conditions?

Needle-like leaves and thick cuticle Signup and view all the answers

Pteridophytes are considered non-vascular plants.

False Signup and view all the answers

What type of roots are associated with nitrogen-fixing cyanobacteria in some gymnosperms?

Coralloid roots Signup and view all the answers

What are the two main classes of angiosperms?

Dicotyledons and Monocotyledons Signup and view all the answers

Bryophytes require water for sexual reproduction.

True Signup and view all the answers

What structure in bryophytes bears male sex organs?

Antheridia Signup and view all the answers

The smallest angiosperm is called __________.

Wolffia Signup and view all the answers

Match each type of plant with its characteristics:

Algae = Chlorophyll-bearing, autotrophic, mainly aquatic Bryophytes = Dependent on water for sexual reproduction Pteridophytes = Main plant body is a sporophyte Angiosperms = Provide food, fuel, and medicines Signup and view all the answers

What kind of plant structure is produced after the fertilization of the zygote in bryophytes?

Sporophyte Signup and view all the answers

The main plant body of bryophytes is called a sporophyte.

False Signup and view all the answers

What type of spore formation do algae primarily exhibit?

Vegetative, asexual, and sexual reproduction Signup and view all the answers

Which of the following classification systems is based on evolutionary relationships?

Phylogenetic classification Signup and view all the answers

Algae are still classified under the kingdom Plantae in modern classification systems.

False Signup and view all the answers

Who proposed the classification system that includes the Five Kingdoms?

Whittaker Signup and view all the answers

The main component of cell walls in green algae is __________.

cellulose Signup and view all the answers

Match the following types of plants with their characteristics:

Bryophytes = Non-vascular plants Pteridophytes = Vascular plants with spores Gymnosperms = Seed-producing plants without flowers Angiosperms = Seed-producing plants with flowers Signup and view all the answers

Which of the following characteristics is emphasized in natural classification systems?

Natural affinities and internal features Signup and view all the answers

Artificial classification systems rely heavily on environmental factors.

False Signup and view all the answers

What is the primary method of classification that separates closely related species by using only a few characteristics?

Artificial classification Signup and view all the answers

What is the classification method that assigns numbers and codes to observable characteristics?

Numerical Taxonomy Signup and view all the answers

Algae can reproduce through vegetative, asexual, and sexual methods.

True Signup and view all the answers

What is the term for the fusion of two similar-sized gametes in algae?

isogamous Signup and view all the answers

The primary photosynthetic pigment found in algae is __________.

chlorophyll Signup and view all the answers

Which of the following is a well-known form of brown algae?

Fucus Signup and view all the answers

Match the following algal forms with their descriptions:

Volvox = Colonial green alga Spirogyra = Filamentous green alga Fucus = Brown alga Porphyra = Red alga Signup and view all the answers

All algae are autotrophic and depend on other organisms for food.

False Signup and view all the answers

What is the process called where algae carry out carbon dioxide fixation?

photosynthesis Signup and view all the answers

What is the primary role of marine algae in aquatic ecosystems?

Increasing levels of dissolved oxygen Signup and view all the answers

Chlorophyceae are commonly referred to as brown algae.

False Signup and view all the answers

Name one commercial product obtained from red algae.

Carrageen Signup and view all the answers

The rigid cell wall of green algae consists of an inner layer of and an outer layer of .

cellulose, pectose Signup and view all the answers

Match the following types of algae with their characteristics:

Chlorophyceae = Dominated by chlorophyll a and b and commonly green. Phaeophyceae = Characterized by the presence of fucoxanthin and brown color. Rhodophyceae = Contains pigments like phycoerythrin, often red in color. Sargassum = A type of brown algae found in marine habitats. Signup and view all the answers

Which type of algae is known for having large amounts of proteins and is used by space travelers?

Chlorella Signup and view all the answers

Phaeophyceae are primarily found in freshwater habitats.

False Signup and view all the answers

What pigment is responsible for the brown color in Phaeophyceae?

Fucoxanthin Signup and view all the answers

Which pigment is NOT found in Phaeophyceae?

Phycoerythrin Signup and view all the answers

All classes of algae reproduce sexually.

False Signup and view all the answers

Name a common habitat for Bryophytes.

Moist shaded areas Signup and view all the answers

The primary stored food in Rhodophyceae is __________.

floridean starch Signup and view all the answers

Match the types of algae with their respective pigments:

Chlorophyceae = Chlorophyll a, b Phaeophyceae = Chlorophyll a, c, fucoxanthin Rhodophyceae = Chlorophyll a, d, phycoerythrin Signup and view all the answers

What type of reproduction is characteristic of Rhodophyceae?

Oogamous sexual reproduction Signup and view all the answers

Chlorophyceae are primarily found in marine environments.

False Signup and view all the answers

List one of the common members of Rhodophyceae.

Polysiphonia Signup and view all the answers

What is the primary role of bryophytes in the ecosystem?

They contribute to plant succession on bare rocks/soil. Signup and view all the answers

Bryophytes have true roots, stems, and leaves.

False Signup and view all the answers

What is the male sex organ called in bryophytes?

Antheridium Signup and view all the answers

The structure where the female gamete is produced in bryophytes is called the ______.

archegonium Signup and view all the answers

Match the following bryophyte parts with their functions:

Rhizoids = Anchor the plant Gametophyte = Produces gametes Sporophyte = Produces spores Antheridium = Male sex organ Signup and view all the answers

What type of reproduction do bryophytes depend on?

Sexual reproduction requiring water Signup and view all the answers

The sporophyte in bryophytes is free-living and can photosynthesize independently.

False Signup and view all the answers

What are the two main types of structures produced in bryophytes for reproductive purposes?

Antheridia and archegonia Signup and view all the answers

What is the primary pigment found in red algae?

r-phycoerythrin Signup and view all the answers

Vegetative reproduction in red algae occurs by fragmentation.

True Signup and view all the answers

Name one form of stored food in brown algae.

laminarin or mannitol Signup and view all the answers

The typical structure that anchors the algal body to the substrate is known as a __________.

holdfast Signup and view all the answers

Match the following algae with their characteristic forms of reproduction:

Brown algae = Biflagellate zoospores Red algae = Fragmentation Green algae = Vegetative and sexual methods Rhodophyceae = Isogamous or oogamous reproduction Signup and view all the answers

Which of the following types of algae is primarily known for producing large amounts of hydrocolloids?

Phaeophyceae Signup and view all the answers

Green algae primarily reproduce asexually through the formation of sporangia.

False Signup and view all the answers

Name one commercial product obtained from Gelidium and Gracilaria.

Agar Signup and view all the answers

The primary role of algae in aquatic ecosystems can be summarized as __________.

primary producers Signup and view all the answers

Match the following algae with their respective characteristics:

Chlamydomonas = Unicellular green alga Ectocarpus = Simple filamentous brown algae Porphyra = Red algae used in food Volvox = Colonial green alga Signup and view all the answers

Which pigment is primarily responsible for the brown color in Phaeophyceae?

Fucoxanthin Signup and view all the answers

Chlorella is known for being a unicellular alga rich in proteins used as a dietary supplement.

True Signup and view all the answers

What is the storage body found in the chloroplasts of green algae called?

Pyrenoid Signup and view all the answers

Which part of the sporophyte in mosses contains spores?

Capsule Signup and view all the answers

Pteridophytes have a gametophyte as the main plant body.

False Signup and view all the answers

Name a common example of pteridophytes.

Fern Signup and view all the answers

The sporophyte of pteridophytes is differentiated into true root, stem, and _______.

leaves Signup and view all the answers

Match the following terms related to pteridophytes with their descriptions:

Sporophyll = Leaf-like appendage that subtends sporangia Strobilus = Compact structure that may form from sporophylls Prothallus = Free-living gametophyte in pteridophytes Xylem = Vascular tissue conducting water and minerals Signup and view all the answers

What is the main function of vascular tissues in pteridophytes?

Transport of water and nutrients Signup and view all the answers

All pteridophytes thrive in warm, dry conditions.

False Signup and view all the answers

What do sporangia produce in pteridophytes?

Spores Signup and view all the answers

What is the major pigment found in Phaeophyceae?

Chlorophyll a, c, and fucoxanthin Signup and view all the answers

Chlorophyceae are primarily found in marine environments.

False Signup and view all the answers

What type of reproduction is primarily exhibited by Rhodophyceae?

Oogamous reproduction Signup and view all the answers

The main stored food in Chlorophyceae is _______.

starch Signup and view all the answers

Match the following classes of algae to their corresponding characteristics:

Chlorophyceae = Green algae with chlorophyll a, b and starch storage Phaeophyceae = Brown algae with major pigments including fucoxanthin Rhodophyceae = Red algae that contain phycoerythrin and lack flagella Dinophyceae = Algae that are often found in marine systems, can be bioluminescent Signup and view all the answers

Which of the following is a common member of the Rhodophyceae class?

Polysiphonia Signup and view all the answers

Brown algae are the only division of algae that reproduce only asexually.

False Signup and view all the answers

What habitat is primarily associated with bryophytes?

Moist shaded areas Signup and view all the answers

What are the male and female sex organs in gametophytes called?

Antheridia and archegonia Signup and view all the answers

Homosporous plants produce two types of spores.

False Signup and view all the answers

What is the dominant phase of pteridophytes?

Sporophyte Signup and view all the answers

The zygote develops into a multicellular __________ known as a sporophyte.

well-differentiated organism Signup and view all the answers

Match the following gymnosperms with their characteristics:

Sequoia = Tallest tree species Pinus = Has mycorrhizal roots Cycas = Has coralloid roots Cedrus = Unbranched stems Signup and view all the answers

Which of the following statements is true regarding gymnosperms?

They produce naked seeds. Signup and view all the answers

What type of roots are associated with nitrogen-fixing cyanobacteria in some gymnosperms?

Coralloid roots Signup and view all the answers

Gymnosperms mainly include shrubs and herbaceous plants.

False Signup and view all the answers

Which pigment is responsible for the brown color in Phaeophyceae?

Fucoxanthin Signup and view all the answers

Green algae primarily store food in the form of starch only.

False Signup and view all the answers

What type of reproduction do Rhodophyceae undergo?

Both asexual and sexual Signup and view all the answers

Name a commercial product obtained from Gelidium and Gracilaria.

Agar Signup and view all the answers

Green algae are primarily characterized by the presence of chlorophyll and .

a, b Signup and view all the answers

All types of algae have flagella.

False Signup and view all the answers

Match the following algae to their classes:

Chlamydomonas = Chlorophyceae Ectocarpus = Phaeophyceae Porphyra = Rhodophyceae Chara = Chlorophyceae Signup and view all the answers

Name a common member of Phaeophyceae.

Kelp Signup and view all the answers

What is the method of asexual reproduction most commonly observed in green algae?

Fragmentation Signup and view all the answers

The major stored food for Chlorophyceae is __________.

starch Signup and view all the answers

Match the following classes of algae with their major pigments:

Chlorophyceae = Chlorophyll a, b Phaeophyceae = Chlorophyll a, c, fucoxanthin Rhodophyceae = Chlorophyll a, d, phycoerythrin Signup and view all the answers

All species of marine algae are used as food for aquatic organisms.

False Signup and view all the answers

What structure in bryophytes bears female sex organs?

Archegonium Signup and view all the answers

What is the main stored food in Phaeophyceae?

Starch Signup and view all the answers

Polysiphonia and Porphyra are examples of Chlorophyceae.

False Signup and view all the answers

What is a primary habitat for Chlorophyceae?

Fresh water Signup and view all the answers

What term describes the cones bearing microsporophylls and microsporangia?

Microsporangiate Signup and view all the answers

In gymnosperms, the male and female gametophytes have independent free-living existence.

False Signup and view all the answers

What structure develops into seeds after fertilization in gymnosperms?

ovules Signup and view all the answers

The __________ grain is the reduced male gametophyte found in gymnosperms.

pollen Signup and view all the answers

Match the following structures with their descriptions:

Microsporangiate = Male strobili Macroscopic = Female strobili Pollen grain = Male gametophyte Megasporangium = Contains megaspores Signup and view all the answers

Where do pollen grains develop in gymnosperms?

In microsporangia Signup and view all the answers

In angiosperms, ovules are naked and not enclosed in any structure.

False Signup and view all the answers

Name the female gametophyte that develops from one of the megaspores inside the megasporangium.

multicellular female gametophyte Signup and view all the answers

Which of the following terms correctly describes the male and female sex organs in gametophytes?

Antheridia and Archegonia Signup and view all the answers

All pteridophytes are homosporous.

False Signup and view all the answers

What classification system is used to categorize pteridophytes?

Four classes Signup and view all the answers

In gymnosperms, the seeds that develop post-fertilization are described as __________.

naked Signup and view all the answers

Match the following gymnosperms with their characteristics:

Sequoia = Tall tree species Pinus = Fungal association through mycorrhiza Cycas = Coralloid roots with N2-fixing cyanobacteria Cedrus = Branched stem structure Signup and view all the answers

What is the primary role of the zygote in pteridophytes?

It develops into a sporophyte. Signup and view all the answers

Gymnosperms are classified as homosporous plants.

False Signup and view all the answers

What is the adaptive feature of gymnosperm leaves that helps in reducing water loss?

Needle-like shape and thick cuticle Signup and view all the answers

Which of the following is NOT a product provided by angiosperms?

Plastics Signup and view all the answers

Bryophytes do not require water for sexual reproduction.

False Signup and view all the answers

What are the two main classes of angiosperms?

Dicotyledons and Monocotyledons Signup and view all the answers

The male and female sex organs in bryophytes are called _ and _ respectively.

antheridia, archegonia Signup and view all the answers

Match the following plant types with their characteristics:

Angiosperms = Produce seeds enclosed in an ovary Gymnosperms = Produce seeds not enclosed in an ovary Bryophytes = Require water for reproduction Pteridophytes = Have a dominant sporophyte generation Signup and view all the answers

Which plant group is characterized by vascular tissues and spores?

Pteridophytes Signup and view all the answers

The main plant body of a bryophyte is called a sporophyte.

False Signup and view all the answers

What is the smallest angiosperm?

Wolffia Signup and view all the answers

What is the primary storage form of food in red algae?

Floridean starch Signup and view all the answers

All red algae are freshwater organisms.

False Signup and view all the answers

What type of reproduction occurs in the majority of brown algae?

Asexual reproduction by biflagellate zoospores Signup and view all the answers

In Rhodophyceae, the predominant pigment responsible for their coloration is __________.

r-phycoerythrin Signup and view all the answers

Match the following types of algae with their stored food:

Phaeophyceae = Laminarin Rhodophyceae = Floridean starch Chlorophyceae = Starch Cyanobacteria = Glycogen Signup and view all the answers

Which pigment is primarily responsible for the brown color in Phaeophyceae?

Fucoxanthin Signup and view all the answers

Chlorophyceae include algae that are green due to the presence of chlorophyll a and b.

True Signup and view all the answers

Name one common genus of brown algae.

Ectocarpus Signup and view all the answers

The storage bodies in the chloroplasts of green algae are called __________.

pyrenoids Signup and view all the answers

Match the following algae with their characteristics:

Chlamydomonas = Unicellular green alga Volvox = Colonial green alga Sargassum = Brown alga, used in food Carrageen = Hydrocolloid from red algae Signup and view all the answers

Which of the following is a characteristic of Phaeophyceae?

Contain fucoxanthin pigment Signup and view all the answers

Agar is a substance derived from Gelidium and Gracilaria, used in food products.

True Signup and view all the answers

What is the primary role of marine algae in aquatic ecosystems?

Primary producers Signup and view all the answers

What is the predominant stage of the life cycle in mosses?

Gametophyte Signup and view all the answers

Liverworts typically grow in dry and sunny environments.

False Signup and view all the answers

What structure do gemmae develop in on liverworts?

gemma cups Signup and view all the answers

Mosses attached to soil through multicellular and branched __________.

rhizoids Signup and view all the answers

Match the following parts of liverworts with their functions:

Thallus = Main body structure Gemmae = Asexual reproduction Sporophyte = Production of spores Gametophyte = Free-living phase Signup and view all the answers

Which of the following is a characteristic of Sphagnum moss?

It can retain a large amount of water. Signup and view all the answers

Mosses only reproduce asexually through fragmentation.

False Signup and view all the answers

How do liverworts primarily reproduce asexually?

by fragmentation of thalli or gemmae formation Signup and view all the answers

What is the primary function of rhizoids in bryophytes?

Anchoring the plant to the substratum Signup and view all the answers

Bryophytes possess true roots, stems, and leaves.

False Signup and view all the answers

What is the male sex organ called in bryophytes?

antheridium Signup and view all the answers

The female sex organ in bryophytes is called __________.

archegonium Signup and view all the answers

Match the following bryophyte structures with their functions:

Gametophyte = Produces gametes Sporophyte = Produces spores Rhizoids = Anchors plant Antheridium = Male sex organ Signup and view all the answers

During the life cycle of bryophytes, which structure is produced directly after the fusion of the male and female gametes?

Zygote Signup and view all the answers

The main body of a bryophyte is diploid.

False Signup and view all the answers

What type of environment do bryophytes typically thrive in?

damp, humid, and shaded localities Signup and view all the answers

What is the dominant phase in the life cycle of pteridophytes?

Sporophyte Signup and view all the answers

Spores in mosses are produced through mitosis.

False Signup and view all the answers

Name two common examples of mosses.

Funaria, Polytrichum, Sphagnum Signup and view all the answers

The small, free-living gametophyte of pteridophytes is called a __________.

prothallus Signup and view all the answers

Match the following types of pteridophytes with their examples:

Selaginella = Heterosporous Equisetum = Horsetail Ferns = Macrophylls Salvinia = Aquatic pteridophyte Signup and view all the answers

What type of vascular tissues do pteridophytes have?

Xylem and phloem Signup and view all the answers

Pteridophytes primarily grow in dry, sandy conditions.

False Signup and view all the answers

What are the leaf-like appendages that subtend sporangia called?

Sporophylls Signup and view all the answers

Which of the following classifications of plants focuses primarily on evolutionary relationships?

Phylogenetic classification Signup and view all the answers

Natural classification systems primarily use superficial morphological traits for categorizing plants.

False Signup and view all the answers

Name the two botanists who provided a classification for flowering plants based on natural affinities.

George Bentham and Joseph Dalton Hooker Signup and view all the answers

The blue-green algae, also known as __________, are now excluded from the plant kingdom.

cyanobacteria Signup and view all the answers

Match the following types of classification with their defining features:

Artificial classification = Based mainly on superficial traits Natural classification = Focuses on natural affinities and internal features Morphological classification = Base classification on observable physical characteristics Phylogenetic classification = Involves evolutionary relationships among organisms Signup and view all the answers

Which of the following is NOT true regarding the Five Kingdom classification?

Fungi are included in the Plantae kingdom. Signup and view all the answers

The classification of plants has remained static over time.

False Signup and view all the answers

The earliest systems of classification were primarily based on __________ characteristics.

morphological Signup and view all the answers

Which of the following pigments is absent in Phaeophyceae?

Chlorophyll b Signup and view all the answers

All species of brown algae are simple, branched forms.

False Signup and view all the answers

Name one commercially important hydrocolloid produced by brown algae.

Alginate Signup and view all the answers

Chlorophyceae are commonly known as __________ algae.

green Signup and view all the answers

Match the following algae with their characteristics:

Chlamydomonas = Unicellular green alga Sargassum = Brown algae Gracilaria = Source of agar Volvox = Colonial green alga Signup and view all the answers

Which of the following is a characteristic of the green algae?

Presence of pyrenoids Signup and view all the answers

Red algae produce water-holding substances such as alginate.

False Signup and view all the answers

What type of reproduction is primarily observed in green algae?

Vegetative reproduction, asexual by zoospores, and sexual reproduction Signup and view all the answers

Which of the following statements is true regarding the sporophyte of mosses?

It contains a capsule that holds spores. Signup and view all the answers

Pteridophytes are the first plants to have vascular tissues.

True Signup and view all the answers

Name two examples of mosses.

Funaria and Sphagnum Signup and view all the answers

The main plant body of pteridophytes is a ________.

sporophyte Signup and view all the answers

Match the following structures to their descriptions in pteridophytes:

Sporophylls = Leaf-like appendages that subtend sporangia Strobili = Compact structures formed by sporophylls Microphylls = Small leaves found in some pteridophytes Macrophylls = Large leaves, such as those found in ferns Signup and view all the answers

Which of the following is NOT a characteristic of pteridophytes?

They can thrive only in sandy soils. Signup and view all the answers

Prothallus is the dominant phase in the life cycle of pteridophytes.

False Signup and view all the answers

Spores are produced by meiosis in ________ cells.

spore mother Signup and view all the answers

What is the main structure responsible for the male gamete production in bryophytes?

Antheridium Signup and view all the answers

Bryophytes are fully independent from water for their reproductive processes.

False Signup and view all the answers

What is the term used for the body of bryophytes that produces gametes?

gametophyte Signup and view all the answers

The female sex organ in bryophytes is known as the _________.

archegonium Signup and view all the answers

Match the following bryophyte structures with their functions:

Rhizoids = Anchorage to the substratum Sporophyte = Produces haploid spores Antheridium = Male gamete production Archegonium = Female gamete production Signup and view all the answers

Which of the following statements best describes a sporophyte in bryophytes?

It derives nourishment from the gametophyte. Signup and view all the answers

The zygote in bryophytes undergoes immediate reduction division.

False Signup and view all the answers

Bryophytes are often referred to as the ________ of the plant kingdom.

amphibians Signup and view all the answers

What do gymnosperms produce in microsporangia and megasporangia?

Microspores and megaspores Signup and view all the answers

The ovules of gymnosperms are enclosed by an ovary wall.

False Signup and view all the answers

What are the two main classes of angiosperms?

Dicotyledons and Monocotyledons Signup and view all the answers

Gymnosperms and angiosperms are both classified as __________.

seed plants Signup and view all the answers

Match the following terms with their definitions:

Protonema = A filamentous stage in the life cycle of mosses Antheridium = The male sex organ in many plants Archegonium = The female sex organ in many plants Sporophyll = A leaf that bears sporangia Signup and view all the answers

What happens after fertilization in plants like gymnosperms?

The zygote develops into a seed Signup and view all the answers

Seeds in gymnosperms are covered by a protective layer.

False Signup and view all the answers

Name one example of a plant that bears archegonia.

Moss Signup and view all the answers

Which of the following groups is excluded from the Plantae kingdom in modern classifications?

Cyanobacteria Signup and view all the answers

Natural classification systems are based primarily on superficial morphological characters.

False Signup and view all the answers

What classification system did Whittaker propose?

Five Kingdom classification Signup and view all the answers

The primary stored food in Pteridophytes is __________.

starch Signup and view all the answers

Match the following plant groups with their characteristics:

Algae = Aquatic organisms that can perform photosynthesis Bryophytes = Non-vascular land plants requiring water for reproduction Gymnosperms = Seed-producing plants with exposed ovules Angiosperms = Flowering plants that produce seeds enclosed in fruits Signup and view all the answers

Which of the following factors has NOT historically influenced plant classification?

Genetic sequencing Signup and view all the answers

The classification method presented by Linnaeus is considered a natural classification system.

False Signup and view all the answers

Name one example of a flowering plant group.

Angiosperms Signup and view all the answers

What is the primary function of marine algae in aquatic ecosystems?

They increase the level of dissolved oxygen. Signup and view all the answers

Phaeophyceae are exclusively found in freshwater habitats.

False Signup and view all the answers

What are the three main classes of algae?

Chlorophyceae, Phaeophyceae, Rhodophyceae Signup and view all the answers

The pigment responsible for the brown color in Phaeophyceae is called __________.

fucoxanthin Signup and view all the answers

Match the following algal features with their respective classes:

Chlorophyceae = May have pyrenoids Phaeophyceae = Primarily marine Rhodophyceae = Contains phycoerythrin Signup and view all the answers

Which of the following are commonly found green algae?

Ulothrix Signup and view all the answers

Vegetative reproduction in green algae generally occurs through the formation of spores.

False Signup and view all the answers

Certain species of marine brown and red algae produce large amounts of __________, which are water holding substances.

hydrocolloids Signup and view all the answers

What is the primary stage of the life cycle of a moss?

Gametophyte stage Signup and view all the answers

Mosses are the first organisms to colonize rocks.

True Signup and view all the answers

What type of habitat do liverworts typically grow in?

Moist, shady habitats Signup and view all the answers

The asexual buds of liverworts are known as __________.

gemmae Signup and view all the answers

Match the following bryophyte structures with their functions:

Seta = Supports the capsule Capsule = Produces spores Rizoid = Anchors the moss to the soil Thallus = The main body structure in liverworts Signup and view all the answers

Which of the following is an ecological benefit provided by mosses?

Reducing soil erosion Signup and view all the answers

The life cycle of moss includes only vegetative reproduction.

False Signup and view all the answers

During sexual reproduction in liverworts, what structures produce male and female gametes?

Antheridia and archegonia Signup and view all the answers

What is the primary development that occurs within microsporangia in gymnosperms?

Pollen grains Signup and view all the answers

In gymnosperms, both male and female gametophytes exist independently as free-living organisms.

False Signup and view all the answers

What do the ovules develop into after fertilization in gymnosperms?

Seeds Signup and view all the answers

Megasporangiate strobili produce __________ gametophytes.

female Signup and view all the answers

Match the type of strobili with their associated sporangia:

Male strobili = Microsporangia Female strobili = Megasporangia Signup and view all the answers

What structure carries male gametes to the archegonia during fertilization in gymnosperms?

Pollen tube Signup and view all the answers

In angiosperms, the seeds are not enclosed within fruits.

False Signup and view all the answers

What is the name given to the multicellular female gametophyte that develops in gymnosperms?

Archegonia Signup and view all the answers

What is a feature unique to gymnosperms in terms of seed structure?

Seeds remain exposed after fertilization. Signup and view all the answers

Angiosperms are classified into three main classes: dicotyledons, monocotyledons, and gymnosperms.

False Signup and view all the answers

Name one group of plants that bear archegonia.

Mosses Signup and view all the answers

The sporophylls responsible for male gamete production in gymnosperms are called __________.

microsporophylls Signup and view all the answers

Match each plant type with its corresponding classification:

Cycas = Gymnosperm Sphagnum = Bryophyte Selaginella = Pteridophyte Chlamydomonas = Alga Signup and view all the answers

In which part of the plant does fertilization occur in gymnosperms?

In the ovule. Signup and view all the answers

Heterospory refers to the production of only one type of spore.

False Signup and view all the answers

Describe the significance of heterospory in plants.

Heterospory allows for more efficient reproduction and adaptation since microspores develop into male gametophytes and megaspores develop into female gametophytes. Signup and view all the answers

Which classification method is currently considered acceptable for plants?

Phylogenetic classification systems Signup and view all the answers

Fungi and cyanobacteria are currently classified under the Kingdom Plantae.

False Signup and view all the answers

What are the five kingdoms proposed by Whittaker (1969)?

Monera, Protista, Fungi, Animalia, Plantae Signup and view all the answers

The primary structure used by early classification systems was called __________.

androecium Signup and view all the answers

Match the following plant groups with their primary characteristics:

Algae = Aquatic photosynthetic organisms Bryophytes = Non-vascular land plants Gymnosperms = Seed-producing plants without flowers Angiosperms = Seed-producing plants with flowers Signup and view all the answers

Who contributed to the natural classification systems for flowering plants?

George Bentham and Joseph Dalton Hooker Signup and view all the answers

Natural classification systems take into account both external and internal features of organisms.

True Signup and view all the answers

What has influenced the evolution of classification systems over time?

Understanding of natural affinities and evolutionary relationships. Signup and view all the answers

What is the primary mode of reproduction in algae?

Vegetative, asexual, and sexual Signup and view all the answers

All types of algae are exclusively found in marine environments.

False Signup and view all the answers

Name the type of reproduction that involves the fusion of two gametes of the same size in algae.

Isogamous Signup and view all the answers

Algae are important for carbon dioxide fixation through __________.

photosynthesis Signup and view all the answers

Match the terms for gamete fusion to their definitions:

Isogamous = Fusion of gametes of similar size Anisogamous = Fusion of gametes of dissimilar size Oogamous = Fusion of a large non-motile gamete with a small motile gamete Signup and view all the answers

Which method of numerical taxonomy uses observable characteristics to classify organisms?

Computational analysis Signup and view all the answers

Cytotaxonomy relies on chromosomal characteristics to help classify organisms.

True Signup and view all the answers

What is the unique feature of zoospores?

They are flagellated and motile. Signup and view all the answers

What is the main plant body of bryophytes called?

Gametophyte Signup and view all the answers

Bryophytes can live in dry conditions without water.

False Signup and view all the answers

What are the male and female sex organs in bryophytes called?

Antheridium and archegonium Signup and view all the answers

The antherozoids produced by the antheridium are __________ in nature.

biflagellate Signup and view all the answers

Match the bryophyte structures with their functions:

Rhizoids = Anchor the plant to the substratum Antheridiophore = Bears male sex organs Archegoniophore = Bears female sex organs Capsule = Produces haploid spores Signup and view all the answers

Which of the following statements about sporophytes is correct?

They depend on the gametophyte for nourishment. Signup and view all the answers

Zygotes in bryophytes undergo reduction division immediately after formation.

False Signup and view all the answers

How do bryophytes typically reproduce?

Sexually, requiring water for the fertilization of gametes. Signup and view all the answers

Which type of plant is known for having exposed seeds?

Gymnosperms Signup and view all the answers

Gymnosperms produce both microspores and megaspores.

True Signup and view all the answers

What is the primary classification of angiosperms?

Dicotyledons and Monocotyledons Signup and view all the answers

After fertilization in gymnosperms, the zygote develops into an ________.

embryo Signup and view all the answers

Match each plant group with its characteristic:

Gymnosperms = Naked seeds Angiosperms = Seeds enclosed in ovary Mosses = Non-vascular Ferns = Vascular with spores Signup and view all the answers

Which of the following groups includes plants that bear archegonia?

All of the above Signup and view all the answers

Angiosperms and gymnosperms are classified together due to their similar reproductive structures.

False Signup and view all the answers

What term describes the production of both male and female spores in plants?

Heterospory Signup and view all the answers

Which of the following statements accurately describes the gametophyte phase of pteridophytes?

It bears antheridia and archegonia as male and female sex organs. Signup and view all the answers

Gymnosperms produce ovules that are enclosed by an ovary wall.

False Signup and view all the answers

What type of spores are produced by heterosporous plants like Selaginella?

macro and micro spores Signup and view all the answers

The process of fusion of the male gamete with the egg in the archegonium leads to the formation of a __________.

zygote Signup and view all the answers

Match the following classes of pteridophytes with their examples:

Psilopsida = Psilotum Lycopsida = Selaginella Sphenopsida = Equisetum Pteropsida = Dryopteris Signup and view all the answers

What adaptation helps gymnosperms like conifers reduce water loss?

Needle-like leaves Signup and view all the answers

Pteridophytes are classified as vascular plants.

True Signup and view all the answers

What type of roots do some gymnosperms like Pinus form in association with fungi?

tap roots Signup and view all the answers

Which classification system is primarily based on evolutionary relationships among organisms?

Phylogenetic classification Signup and view all the answers

Fungi and members of the Monera are included in the plant kingdom according to modern classification systems.

False Signup and view all the answers

What are the five kingdoms proposed by Whittaker in his classification system?

Monera, Protista, Fungi, Animalia, Plantae Signup and view all the answers

Natural classification systems take into account both external and _____ characteristics.

internal Signup and view all the answers

Match the following classes of plants with their characteristics:

Bryophytes = Non-vascular plants that depend on water for reproduction Gymnosperms = Seed-producing plants with unenclosed ovules Angiosperms = Flowering plants that produce seeds enclosed in fruit Pteridophytes = Vascular plants that reproduce via spores Signup and view all the answers

Which of the following characteristics is a major consideration in natural classification systems?

Natural affinities among organisms Signup and view all the answers

Artificial classification systems give more weight to vegetative characteristics than to sexual characteristics.

True Signup and view all the answers

Which two botanists are noted for providing a classification system for flowering plants?

George Bentham and Joseph Dalton Hooker Signup and view all the answers

What term describes the method of reproduction where fragmentation leads to the development of new thalli in algae?

Vegetative reproduction Signup and view all the answers

All algae are exclusively found in aquatic environments.

False Signup and view all the answers

Name a type of spore commonly produced by algae during asexual reproduction.

Zoospore Signup and view all the answers

The fusion of two gametes that are similar in size and flagellated is known as __________.

isogamous Signup and view all the answers

Match the types of algae with their examples:

Green algae = Volvox Brown algae = Fucus Red algae = Porphyra Filamentous algae = Spirogyra Signup and view all the answers

What is a significant role played by algae in the ecosystem?

They fix carbon dioxide through photosynthesis. Signup and view all the answers

Cytotaxonomy relies on cytological information such as chromosome number and structure.

True Signup and view all the answers

What are the two types of gametes that can undergo fusion in sexual reproduction in algae?

Flagellated and non-flagellated Signup and view all the answers

Which pigment is primarily responsible for the brown color in Phaeophyceae?

Fucoxanthin Signup and view all the answers

Green algae are typically pink due to the dominance of specific pigments.

False Signup and view all the answers

Name one common genus of brown algae.

Ectocarpus Signup and view all the answers

The storage bodies found in the chloroplasts of green algae are called __________.

pyrenoids Signup and view all the answers

What is the primary ecological role of mosses?

They decompose rocks, aiding higher plant growth. Signup and view all the answers

Match the following classes of algae with their characteristics:

Chlorophyceae = Contains chlorophyll a and b, found in freshwater and marine environments Phaeophyceae = Primarily marine, includes large forms like kelp Rhodophyceae = Contains phycoerythrin, often found in deeper waters Chlorella = Unicellular and rich in proteins, used as a food supplement Signup and view all the answers

Liverworts are typically found in dry, sunny environments.

False Signup and view all the answers

Which of the following is NOT a method of reproduction seen in algae?

Regeneration Signup and view all the answers

What are gemmae in liverworts?

Asexual buds that develop in receptacles called gemma cups. Signup and view all the answers

Carrageenan is a hydrocolloid produced by red algae.

True Signup and view all the answers

The male and female sex organs in mosses are called and respectively.

antheridia, archegonia Signup and view all the answers

What is the primary role of algae in aquatic ecosystems?

Primary producers of energy-rich compounds Signup and view all the answers

Which part of a moss sporophyte is responsible for spore production?

Capsule Signup and view all the answers

Match the types of reproduction in liverworts and mosses:

Liverworts = Fragmentation and gemmae Mosses = Fragmentation and budding Signup and view all the answers

The __________ stage of moss develops from a spore and is creeping and branched.

protonema Signup and view all the answers

All bryophytes primarily reproduce sexually.

False Signup and view all the answers

What is a characteristic feature of gymnosperms?

Seeds remain exposed after fertilization Signup and view all the answers

Gymnosperms and angiosperms both produce seeds, thus they are classified together.

False Signup and view all the answers

What are the two types of spores produced by gymnosperms?

Microspores and megaspores Signup and view all the answers

The male gamete is released by the _______ tube into the ovule.

pollen Signup and view all the answers

Match the plant group with its corresponding feature:

Gymnosperms = Naked seeds Angiosperms = Enclosed seeds Pteridophytes = Spores for reproduction Bryophytes = Require water for reproduction Signup and view all the answers

Which of the following best describes heterospory?

Production of two different types of spores Signup and view all the answers

Name one example of a gymnosperm.

Cycas Signup and view all the answers

The ovule in gymnosperms is enclosed by an ovary wall after fertilization.

False Signup and view all the answers

What is the storage form of food in Rhodophyceae?

Floridean starch Signup and view all the answers

All members of Rhodophyceae are exclusively found in freshwater environments.

False Signup and view all the answers

Identify one common reproductive method for brown algae.

Fragmentation Signup and view all the answers

The flagella of the gametes in brown algae are __________ and laterally attached.

unequal Signup and view all the answers

Match the following algal classes with their primary characteristics:

Phaeophyceae = Food stored as laminarin Rhodophyceae = Predominance of r-phycoerythrin Chlorophyceae = Cell walls primarily cellulose Bacillariophyceae = Siliceous cell wall Signup and view all the answers

Which pigment is primarily responsible for the brown color in Phaeophyceae?

Fucoxanthin Signup and view all the answers

The chloroplasts in Chlorophyceae can adopt various shapes such as spiral or ribbon-shaped.

True Signup and view all the answers

Name one commercial product obtained from algae.

Agar Signup and view all the answers

Certain marine algae produce large amounts of __________, which are used commercially.

hydrocolloids Signup and view all the answers

Match the following algal species with their respective classes:

Chlamydomonas = Chlorophyceae Ectocarpus = Phaeophyceae Porphyra = Rhodophyceae Chara = Chlorophyceae Signup and view all the answers

What method of reproduction is common in green algae?

Fragmentation Signup and view all the answers

All members of Phaeophyceae are found exclusively in freshwater habitats.

False Signup and view all the answers

What is the primary role of marine algae in aquatic ecosystems?

Primary producers of energy-rich compounds Signup and view all the answers

What type of plant body is dominant in pteridophytes?

Sporophyte Signup and view all the answers

Spores in mosses are formed after mitosis.

False Signup and view all the answers

Name one common example of a moss.

Funaria Signup and view all the answers

Pteridophytes are the first terrestrial plants to possess ________ tissues.

vascular Signup and view all the answers

Match the following terms with their descriptions:

Sporangia = Structures that produce spores Strobili = Compact structures bearing sporophylls Prothallus = Free-living gametophyte of pteridophytes Microphylls = Small leaves found in some pteridophytes Signup and view all the answers

Which of the following habitats do pteridophytes prefer?

Cool, damp, shady places Signup and view all the answers

The gametophyte phase in pteridophytes can grow under sandy soil conditions.

False Signup and view all the answers

What is the main organ of spore production in pteridophytes?

Sporangia Signup and view all the answers

What is the dominant phase of pteridophytes?

Sporophyte Signup and view all the answers

Gymnosperms have seeds that are enclosed by an ovary wall.

False Signup and view all the answers

Name one genus of gymnosperms.

Pinus Signup and view all the answers

What is the predominant stage of the life cycle of a moss?

Gametophyte Signup and view all the answers

All mosses are capable of vegetative reproduction.

False Signup and view all the answers

The female gamete is present in the __________ of pteridophytes.

archegonium Signup and view all the answers

Match the following classes of pteridophytes with their examples:

Psilopsida = Psilotum Lycopsida = Selaginella, Lycopodium Sphenopsida = Equisetum Pteropsida = Dryopteris, Pteris, Adiantum Signup and view all the answers

What are the specialized structures called that aid in asexual reproduction in liverworts?

gemmae Signup and view all the answers

Which of the following statements is true regarding gymnosperms?

They have a tap root system. Signup and view all the answers

The ability of Sphagnum moss to retain water makes it useful as _____ material.

packing Signup and view all the answers

Match the following terms related to bryophytes with their descriptions:

Liverworts = Moist, shady habitats with thalloid structure Mosses = Gametophyte stage predominant in life cycle Gemmae = Asexual reproductive structures in liverworts Sphagnum = Moss known for water retention and peat production Signup and view all the answers

What process takes place when a male gamete fuses with an egg in pteridophytes?

Fertilization Signup and view all the answers

All gymnosperms are heterosporous.

False Signup and view all the answers

Which of the following statements about liverworts is true?

They can reproduce asexually through fragmentation. Signup and view all the answers

Mosses are the first organisms to colonize rocks.

True Signup and view all the answers

What type of habitats do liverworts typically grow in?

moist, shady habitats Signup and view all the answers

What is the primary form of carbohydrate storage in vegetative cells of brown algae?

Laminarin Signup and view all the answers

Red algae primarily reproduce sexually by oogamous reproduction.

False Signup and view all the answers

Name one common form of brown algae.

Sargassum Signup and view all the answers

The primary pigment that gives red algae their color is called __________.

r-phycoerythrin Signup and view all the answers

Match the following types of algae with their primary reproductive methods:

Brown algae = Biflagellate zoospores Red algae = Vegetative fragmentation Green algae = Multiple forms including sexual and asexual Rhodophyceae = Oogamous or isogamous Signup and view all the answers

Which classification method is based on evolutionary relationships between organisms?

Phylogenetic classification Signup and view all the answers

Fungi are classified within the plant kingdom according to modern classification systems.

False Signup and view all the answers

Name two key figures associated with the natural classification system for flowering plants.

George Bentham and Joseph Dalton Hooker Signup and view all the answers

The __________ classification systems were originally based on superficial morphological characters.

artificial Signup and view all the answers

Match the following classifications with their definitions:

Artificial classification = Based on a few morphological characteristics Natural classification = Based on natural affinities of organisms Phylogenetic classification = Based on evolutionary relationships Morphological classification = Focus on physical traits and structure Signup and view all the answers

What was one limitation of early classification systems proposed by Linnaeus?

They treated vegetative and sexual features equally. Signup and view all the answers

In modern classification, algae are still considered part of the plant kingdom.

False Signup and view all the answers

What did the earliest classification systems primarily rely on for grouping organisms?

Gross superficial morphological characters Signup and view all the answers

What pigment is primarily found in brown algae?

Fucoxanthin Signup and view all the answers

Chlorophyceae are also known as red algae.

False Signup and view all the answers

Name one type of marine algae that produce hydrocolloids.

Alginate or Carrageenan Signup and view all the answers

Chlorella is a unicellular alga rich in __________.

proteins Signup and view all the answers

Match the following algae with their classifications:

Porphyra = Rhodophyceae Ectocarpus = Phaeophyceae Chlamydomonas = Chlorophyceae Chara = Chlorophyceae Signup and view all the answers

Which of the following methods of reproduction is NOT commonly found in green algae?

Fertilization of pollen Signup and view all the answers

Green algae have cell walls made only of pectose.

False Signup and view all the answers

What are storage bodies in chloroplasts called?

Pyrenoids Signup and view all the answers

Which of the following is a class of angiosperms?

Monocotyledons Signup and view all the answers

Bryophytes do not require water for sexual reproduction.

False Signup and view all the answers

What is the primary structure of gametophytes in bryophytes?

Gametophyte Signup and view all the answers

What are the male and female gametes produced by antheridia and archegonia called, respectively?

Antherozoids and Eggs Signup and view all the answers

The smallest angiosperm is called __________.

Wolffia Signup and view all the answers

Match the following plant types with their characteristics:

Angiosperms = Plants that bear flowers and produce seeds Gymnosperms = Seed-producing plants without flowers Bryophytes = Non-vascular plants requiring water for reproduction Pteridophytes = Vascular plants with true roots, stems, and leaves Signup and view all the answers

All gymnosperms have their ovules enclosed by an ovary wall.

False Signup and view all the answers

What is the dominant phase of pteridophytes?

Sporophyte Signup and view all the answers

Which group of plants is characterized by having true vascular tissues?

Pteridophytes Signup and view all the answers

The zygote in pteridophytes produces haploid spores.

True Signup and view all the answers

The fusion of the male gamete with the egg in the archegonium results in the formation of a __________.

zygote Signup and view all the answers

What type of reproductive structures do pteridophytes bear?

Sporangia Signup and view all the answers

Match the following plant classes with their examples:

Psilopsida = Psilotum Lycopsida = Selaginella Sphenopsida = Equisetum Pteropsida = Dryopteris Signup and view all the answers

Which of the following is a characteristic feature of the leaves in gymnosperms?

Needle-like and thick cuticle Signup and view all the answers

Homosporous plants produce two types of spores.

False Signup and view all the answers

Name one example of a heterosporous plant.

Selaginella Signup and view all the answers

What is the primary focus of numerical taxonomy?

Processing observable characteristics using computers Signup and view all the answers

Cytotaxonomy relies solely on behavioral characteristics of organisms.

False Signup and view all the answers

Name one of the three types of methods algae use for reproduction.

Vegetative, asexual, or sexual Signup and view all the answers

The fusion between one large, non-motile female gamete and a smaller, motile male gamete is termed __________.

oogamous Signup and view all the answers

Match the types of algae with their examples:

Green algae = Volvox Brown algae = Fucus Red algae = Porphyra Filamentous algae = Spirogyra Signup and view all the answers

Which of the following algae forms massive plant bodies in marine environments?

Laminaria Signup and view all the answers

Algae contribute to over half of the total carbon dioxide fixation on Earth.

True Signup and view all the answers

What is the method by which algae primarily reproduce asexually?

Production of spores Signup and view all the answers

What is the male sex organ in bryophytes called?

Antheridium Signup and view all the answers

Bryophytes can survive in dry conditions without any water.

False Signup and view all the answers

What type of structure do bryophytes use to anchor themselves to the substrate?

Rhizoids Signup and view all the answers

The zygote in bryophytes develops into a ________ that is attached to the gametophyte.

sporophyte Signup and view all the answers

Match the following structures with their corresponding function in bryophytes:

Antheridium = Produces male gametes Archegonium = Produces female gametes Sporophyte = Produces spores Rhizoids = Anchors the plant Signup and view all the answers

In which environment do bryophytes predominantly thrive?

Damp and shaded localities Signup and view all the answers

The main plant body of bryophytes is diploid.

False Signup and view all the answers

What type of division do some cells of the sporophyte undergo to produce haploid spores?

Meiosis Signup and view all the answers

Which of the following classifications is NOT considered artificial?

Phylogenetic classification systems Signup and view all the answers

Natural classification systems give equal weight to vegetative and sexual characteristics.

False Signup and view all the answers

What major advancements have been made in the understanding of the plant kingdom since earlier classifications?

Fungi and certain members of Monera and Protista have been excluded from Plantae. Signup and view all the answers

The earliest classification systems were based on ________ characteristics such as habit and color.

superficial Signup and view all the answers

Match the following types of plants with their classification:

Bryophytes = Non-vascular plants Pteridophytes = Vascular spore-bearing plants Gymnosperms = Seed-producing plants without flowers Angiosperms = Flowering plants Signup and view all the answers

The system proposed by Whittaker in 1969 classified living organisms into how many kingdoms?

Five Signup and view all the answers

Cyanobacteria are classified as ‘algae’ in the modern classification system.

False Signup and view all the answers

Who were the botanists that provided a natural classification system for flowering plants?

George Bentham and Joseph Dalton Hooker. Signup and view all the answers

Which of the following groups of plants possess vascular tissues?

Pteridophytes Signup and view all the answers

The dominant phase in the life cycle of pteridophytes is the sporophytic plant body.

True Signup and view all the answers

Name one common example of a moss.

Funaria Signup and view all the answers

Spores in mosses are formed after __________.

meiosis Signup and view all the answers

Which of the following features is characteristic of pteridophytes?

They possess true roots, stems, and leaves. Signup and view all the answers

Match the following types of leaf structures with their descriptions:

Microphylls = Small leaves, as in Selaginella Macrophylls = Large leaves, as in ferns Sporophylls = Leaf-like appendages that bear sporangia Strobili = Compact structures formed by sporophylls Signup and view all the answers

Pteridophytes are commonly found in dry and sunny environments.

False Signup and view all the answers

What is the term for the free-living, photosynthetic gametophyte in pteridophytes?

Prothallus Signup and view all the answers

What are the male strobili bearing microsporophylls referred to as?

Microsporangiate strobili Signup and view all the answers

In gymnosperms, both male and female gametophytes have a free-living existence.

False Signup and view all the answers

What develops from the ovules after fertilization?

Seeds Signup and view all the answers

The structure that carries male gametes toward the archegonia in ovules is called a __________.

pollen tube Signup and view all the answers

Match the following terms with their definitions:

Microspores = Develop into pollen grains Megaspores = Form female gametophyte Pollen grain = Male gametophyte of gymnosperms Ovule = Structure enclosing megasporangium Signup and view all the answers

What is the primary difference between angiosperms and gymnosperms regarding their seeds?

Angiosperms have seeds enclosed in fruits. Signup and view all the answers

Megasporophylls are only found in male strobili.

False Signup and view all the answers

What is the function of archegonia in the female gametophyte?

To produce female gametes Signup and view all the answers

Which form of food storage is primarily found in Rhodophyceae?

Floridean starch Signup and view all the answers

Brown algae reproduce only through sexual reproduction.

False Signup and view all the answers

What pigment is predominantly found in red algae?

r-phycoerythrin Signup and view all the answers

The vegetative cells of brown algae typically have a ___________ wall covered by a gelatinous coating.

cellulosic Signup and view all the answers

Match the following terms with their definitions:

Isogamous = Fusion of gametes of similar size Anisogamous = Fusion of gametes of different sizes Oogamous = Fusion of a large female gamete and a small male gamete Fragmentation = A method of asexual reproduction involving breaking off pieces Signup and view all the answers

Which of the following classifications is based on evolutionary relationships among organisms?

Phylogenetic classification Signup and view all the answers

Fungi are currently classified under the kingdom Plantae.

False Signup and view all the answers

Name one group of plants that is classified under the kingdom Plantae.

Angiosperms Signup and view all the answers

The system of classification that was notably proposed by George Bentham and Joseph Dalton Hooker is called __________ classification.

natural Signup and view all the answers

Match each type of plant with its characteristics:

Algae = Primarily aquatic organisms Bryophytes = Non-vascular plants that require water for reproduction Gymnosperms = Seed-producing plants without flowers Angiosperms = Plants that produce flowers and seeds enclosed in fruit Signup and view all the answers

Which factor is primarily considered in artificial classification systems?

Environmental factors Signup and view all the answers

Natural classification systems give equal weight to vegetative and sexual characteristics.

False Signup and view all the answers

What distinguishes angiosperms from gymnosperms?

Angiosperms produce flowers and seeds enclosed in fruit. Signup and view all the answers

What is the term for the fusion of two similar gametes in algae, as seen in Ulothrix?

Isogamous Signup and view all the answers

All algae reproduce exclusively through sexual methods.

False Signup and view all the answers

Which type of reproduction involves the development of new plants from fragments in algae?

Vegetative reproduction Signup and view all the answers

Cytotaxonomy relies on cytological information such as chromosome number and __________.

structure Signup and view all the answers

Match the following types of algae with their respective examples.

Green Algae = Volvox Brown Algae = Laminaria Red Algae = Porphyra Cyanobacteria = Oscillatoria Signup and view all the answers

Which of the following algae is known to form massive plant bodies?

Kelp Signup and view all the answers

Zoospores in algae are non-motile spores.

False Signup and view all the answers

Name one habitat where algae can be found.

Moist stones or soils Signup and view all the answers

What is the primary stored food in brown algae (Phaeophyceae)?

Mannitol Signup and view all the answers

Red algae (Rhodophyceae) have a cell wall that is absent.

False Signup and view all the answers

What type of reproduction is characterized by the fusion of male and female gametes in Rhodophyceae?

Oogamous Signup and view all the answers

The primary pigment found in green algae is __________.

Chlorophyll a, b Signup and view all the answers

Match the algae class with its corresponding characteristic:

Chlorophyceae = Freshwater, brackish and saltwater Phaeophyceae = Brown algae, contains fucoxanthin Rhodophyceae = Typically found in marine environments Bryophytes = Includes mosses and liverworts Signup and view all the answers

Which class of algae is primarily characterized by an equal number of flagella located at the apex?

Chlorophyceae Signup and view all the answers

Bryophytes typically thrive in dry environments.

False Signup and view all the answers

Name one common member of the red algae group.

Polysiphonia Signup and view all the answers

Which of the following is NOT a commercially important product provided by angiosperms?

Metals Signup and view all the answers

All angiosperms are trees.

False Signup and view all the answers

Name the two classes that angiosperms are divided into.

Dicotyledons and monocotyledons Signup and view all the answers

The main plant body of a bryophyte is called a __________.

gametophyte Signup and view all the answers

Match the following plant groups with their characteristics:

Algae = Simple thalloid organisms, aquatic Bryophytes = Dependent on water for reproduction Pteridophytes = Sporophytes with vascular tissues Angiosperms = Seed-producing plants with flowers Signup and view all the answers

Which method of reproduction is demonstrated by bryophytes?

Sexual reproduction and asexual reproduction Signup and view all the answers

Pteridophytes are considered non-vascular plants.

False Signup and view all the answers

What is the function of sporangia in pteridophytes?

To produce spores Signup and view all the answers

What is the primary method of reproduction in algae that involves the development of a new organism from a fragment?

Vegetative reproduction Signup and view all the answers

Cytotaxonomy relies on chromosome number and structure to help classify organisms.

True Signup and view all the answers

Name one characteristic feature of algae.

Chlorophyll-bearing Signup and view all the answers

The most common type of spore produced in asexual reproduction of algae is called __________.

zoospore Signup and view all the answers

Match the following types of algal reproduction with their definitions:

Isogamous = Fusion of gametes similar in size Anisogamous = Fusion of gametes dissimilar in size Oogamous = Fusion between a large, non-motile female gamete and a smaller, motile male gamete Asexual = Reproduction without fusion of gametes Signup and view all the answers

Which of the following is a method of sexual reproduction in algae?

Fusion of gametes Signup and view all the answers

Algae only occur in marine environments and cannot be found in fresh water.

False Signup and view all the answers

What do algae primarily contribute to the global carbon dioxide fixation?

At least half Signup and view all the answers

What is a primary producer of energy-rich compounds in aquatic environments?

Marine algae Signup and view all the answers

Chlorophyceae are commonly known as red algae.

False Signup and view all the answers

Name one type of commercial product derived from red algae.

Carrageenan Signup and view all the answers

The rigid cell wall of green algae consists of an inner layer of __________ and an outer layer of pectose.

cellulose Signup and view all the answers

Which of the following pigments is present in brown algae?

All of the above Signup and view all the answers

Match the type of algae with their characteristic:

Chlorophyceae = Green algae Phaeophyceae = Brown algae Rhodophyceae = Red algae Signup and view all the answers

Members of Phaeophyceae can reach heights of up to 100 meters.

True Signup and view all the answers

What is the name of the unicellular alga that is rich in proteins and used as a food supplement?

Chlorella Signup and view all the answers

What is the dominant phase in the life cycle of pteridophytes?

Sporophyte Signup and view all the answers

All pteridophytes are adapted to dry environments.

False Signup and view all the answers

Name one genus of mosses.

Funaria Signup and view all the answers

Pteridophytes possess vascular tissues called and .

xylem and phloem Signup and view all the answers

Match the following pteridophytes with their descriptions:

Horsetails = Known for their jointed stems Ferns = Have large, divided leaves Selaginella = Known as a club moss Equisetum = Ancient lineage with hollow stems Signup and view all the answers

What structures bear sporangia in pteridophytes?

Sporophylls Signup and view all the answers

Spores in pteridophytes are formed by mitosis.

False Signup and view all the answers

What is the term for the free-living photosynthetic phase in pteridophytes?

Prothallus Signup and view all the answers

What part of the liverwort sporophyte is responsible for anchoring it to the substrate?

Foot Signup and view all the answers

The predominant stage of the life cycle of a moss is the sporophyte.

False Signup and view all the answers

What type of environment do liverworts typically grow in?

Moist, shady habitats Signup and view all the answers

The specialized structures in liverworts that develop into new individuals are called __________.

gemmae Signup and view all the answers

Match the following components of the moss life cycle with their descriptions:

Protonema = Creeping, green, branched stage Leafy stage = Upright structure bearing leaves Antheridia = Male sex organs Archegonia = Female sex organs Signup and view all the answers

Which moss species is noted for its ability to hold water and is often used for packing material?

Sphagnum Signup and view all the answers

Mosses can reproduce vegetatively through fragmentation and budding.

True Signup and view all the answers

What are the two main groups into which bryophytes are divided?

Liverworts and mosses Signup and view all the answers

What structure in male gametophytes is responsible for producing antherozoids?

Antheridia Signup and view all the answers

Gymnosperms have their ovules enclosed by an ovary wall.

False Signup and view all the answers

Name one genus of pteridophytes that is classified as heterosporous.

Selaginella or Salvinia Signup and view all the answers

The dominant phase of the pteridophytes is the __________.

sporophyte Signup and view all the answers

Match the following classes of gymnosperms with their examples:

Cycadopsida = Cycas Coniferopsida = Pinus Ginkgopsida = Ginkgo biloba Gnetopsida = Ephedra Signup and view all the answers

Which of the following adaptations help gymnosperms reduce water loss?

Thick cuticle Signup and view all the answers

What is the role of mycorrhiza in some gymnosperms?

Fungal association that aids in nutrient absorption Signup and view all the answers

Pteridophytes produce only one kind of spore in most cases.

True Signup and view all the answers

What pigment primarily gives Rhodophyceae their red color?

r-phycoerythrin Signup and view all the answers

All members of Rhodophyceae are freshwater species.

False Signup and view all the answers

What is the method of vegetative reproduction in red algae?

fragmentation Signup and view all the answers

Food in brown algae is generally stored as __________.

laminarin or mannitol Signup and view all the answers

Match the following algae with their characteristics:

Ectocarpus = Common brown alga Dictyota = Brown algae with branched structure Laminaria = Kelp species Sargassum = Floating brown algae Signup and view all the answers

Which pigment is responsible for the brown color in Phaeophyceae?

Fucoxanthin Signup and view all the answers

All members of the Chlorophyceae are multicellular organisms.

False Signup and view all the answers

Name one commercially significant product obtained from red algae.

Carrageen Signup and view all the answers

Green algae have a rigid cell wall made of _______ and pectose.

cellulose Signup and view all the answers

Which of the following algae are known for their ecological role as primary producers?

Laminaria Signup and view all the answers

Match the following algae with their class:

Chlamydomonas = Chlorophyceae Fucus = Phaeophyceae Porphyra = Rhodophyceae Spirogyra = Chlorophyceae Signup and view all the answers

Asexual reproduction in green algae occurs mainly through the formation of flagellated zoospores.

True Signup and view all the answers

Certain species of algae store food in the form of ______ droplets.

oil Signup and view all the answers

Which of the following pigments is found in Phaeophyceae?

Fucoxanthin Signup and view all the answers

All classes of algae reproduce sexually.

False Signup and view all the answers

What is the primary stored food in Chlorophyceae?

Starch Signup and view all the answers

The major stored food in Rhodophyceae is __________.

Floridean starch Signup and view all the answers

Match the following classes of algae with their major characteristics:

Chlorophyceae = Cell wall made of cellulose Phaeophyceae = Includes mannitol and laminarin as stored food Rhodophyceae = Contains phycoerythrin and has an absent flagellar insertion Signup and view all the answers

Which habitat is most commonly associated with Bryophytes?

Moist shaded areas Signup and view all the answers

The cell wall of Phaeophyceae is primarily made of chitin.

False Signup and view all the answers

Name a common member of Rhodophyceae.

Polysiphonia Signup and view all the answers

What is the main plant body of bryophytes called?

Gametophyte Signup and view all the answers

Bryophytes can survive in dry areas without needing water for reproduction.

False Signup and view all the answers

What type of reproductive structures do bryophytes possess?

Multicellular sex organs Signup and view all the answers

The male sex organ in bryophytes is called __________.

antheridium Signup and view all the answers

Match the following bryophyte structures with their descriptions:

Antheridiophore = Structure that bears male sex organs Archegoniophore = Structure that bears female sex organs Sporophyte = Multicellular body attached to gametophyte Rhizoids = Root-like structures for anchorage Signup and view all the answers

Which statement correctly describes the sporophyte in bryophytes?

It is attached to the gametophyte and receives nourishment. Signup and view all the answers

Zygotes in bryophytes undergo immediate reduction division to produce spores.

False Signup and view all the answers

What type of reproduction do bryophytes primarily depend on?

Sexual reproduction Signup and view all the answers

Which of the following is a characteristic of gymnosperms?

Seeds remain exposed after fertilization Signup and view all the answers

All angiosperms are divided into two classes: dicotyledons and polycotyledons.

False Signup and view all the answers

What are the male and female structures that produce spores in gymnosperms called?

microsporophylls and megasporophylls Signup and view all the answers

Gymnosperms produce seeds that remain ________ after fertilization.

exposed Signup and view all the answers

Match the following plant groups with their characteristics:

Gymnosperms = Naked-seeded plants Angiosperms = Enclosed seeds in ovaries Pteridophytes = Vascular plants without seeds Bryophytes = Non-vascular plants Signup and view all the answers

Which group of plants is known for bearing archegonia?

Both B and C Signup and view all the answers

Heterospory refers to the production of two different types of spores.

True Signup and view all the answers

What is the main difference between gymnosperms and angiosperms?

Gymnosperms have seeds that are not enclosed by an ovary, while angiosperms have seeds enclosed within an ovary. Signup and view all the answers

Study Notes

Taxonomy

Modern taxonomy uses multiple sources including fossil evidence, chemical constituents, and numerical data to classify organisms.
Numerical Taxonomy uses computer analysis to assign equal importance to observable characteristics.
Cytotaxonomy focuses on cytological information like chromosome number and structure.
Chemotaxonomy studies the chemical constituents of a plant to aid in classification.

Algae

Algae are chlorophyll-bearing, simple, thalloid, autotrophic organisms primarily found in aquatic environments.
They are highly diverse in size and form, ranging from unicellular to massive plant bodies like kelps.
Algae reproduce by vegetative, asexual, and sexual methods.
Vegetative Reproduction: Occurs through fragmentation where each fragment develops into a thallus.
Asexual Reproduction: Takes place through the production of motile zoospores.
Sexual Reproduction: Involves the fusion of two gametes, which can be isogamous (similar in size), anisogamous (dissimilar in size), or oogamous (one large, static female gamete and one smaller, motile male gamete).
Algae are crucial for carbon dioxide fixation and the basis of aquatic food cycles.
Many species are used as food, and others produce commercially valuable substances like algin and carrageen.

Chlorophyceae (Green Algae)

Have a plant body that can be unicellular, colonial, or filamentous.
Are usually green due to the dominance of chlorophyll a and b.
Contain storage bodies called pyrenoids located in their chloroplasts, which store protein and starch.
Some store food in the form of oil droplets.
Have a rigid cell wall made of cellulose and pectose.
Reproduce vegetatively by fragmentation and asexually by zoospores.
Sexual reproduction can be isogamous, anisogamous, or oogamous.
Examples include Chlamydomonas, Volvox, Ulothrix, Spirogyra, and Chara.

Phaeophyceae (Brown Algae)

Found primarily in marine habitats.
Exhibit great variation in size and form, ranging from simple filamentous forms to massive kelps.
Possess chlorophyll a, c, carotenoids, and xanthophylls, which give them their brown color.
Reproduce asexually by non-motile spores.
Sexual reproduction is oogamous.
Examples include Polysiphonia, Porphyra, Gracilaria, and Gelidium.

Bryophytes

Include mosses and liverworts commonly found in moist, shaded areas.
Gametophytes bear male (antheridia) and female (archegonia) sex organs.
Water is required for the transfer of male gametes (antherozoids) to the archegonia.
Fusion of male and female gametes results in the formation of a zygote, giving rise to a multicellular sporophyte.
The sporophyte is the dominant phase in bryophytes.

Pteridophytes

Possess true roots, stems, and leaves with well-differentiated vascular tissues.
Sporophytes bear sporangia, which produce spores.
Spores germinate to form gametophytes that require cool, damp environments.
Gametophytes bear antheridia and archegonia.
Water is required for fertilization.
Zygote produces a sporophyte.
Most pteridophytes are homosporous (producing one type of spore).
Some, like Selaginella and Salvinia, are heterosporous (producing two types of spores).

Gymnosperms

Have ovules that are not enclosed by an ovary wall, remaining exposed before and after fertilization.
Seeds are not covered, hence the name "naked seed".
Include medium-sized trees, tall trees, or shrubs.
Roots are generally tap roots, often with mycorrhizae or specialized coralloid roots associated with nitrogen-fixing cyanobacteria.
Leaves are adapted to withstand extreme temperatures, humidity, and wind.
Heterosporous: produce haploid microspores and megaspores.
Examples include Sequoia, Pinus, Cedrus, and Cycas.

Angiosperms

Exceptionally large group of plants with a wide range of habitats.
Include species from the smallest Wolffia to tall Eucalyptus trees.
Provide food, fodder, fuel, medicines, and various other commercially important products.
Divided into two classes: dicotyledons and monocotyledons.

Plant Kingdom: Introduction

The Plant Kingdom has been reclassified, excluding fungi, bacteria, and protists with cell walls.
Current classification includes algae, bryophytes, pteridophytes, gymnosperms, and angiosperms.
Early classification systems were artificial, relying on superficial features like shape, color, and leaf arrangement.
These systems were based on vegetative characters or androecium structure, not reflecting evolutionary relationships.
Natural classification systems consider internal features like anatomy, embryology, and phytochemistry, reflecting natural affinities.
Phylogentic classification, based on evolutionary relationships and common ancestors, is currently accepted.
Numerical taxonomy uses computer analysis of all observable characteristics, assigning equal importance to each.
Cytotaxonomy examines chromosome structure and behavior.
Chemotaxonomy utilizes chemical constituents to clarify relationships.

Algae

Algae are chlorophyll-bearing and largely aquatic, found in diverse habitats including moist soils, wood, and associations with fungi and animals.
Algae exhibit varying sizes and forms, ranging from unicellular to colonial and filamentous.
Reproduction occurs through vegetative (fragmentation), asexual (spore production), and sexual methods.
Zoospores, motile reproductive cells, germinate into new plants.
Sexual reproduction can be isogamous (identical gametes), anisogamous (dissimilar gametes), or oogamous (one large, non-motile egg and one small, motile sperm).
Algae are essential as primary producers, contributing to aquatic food chains and oxygen production.
Porphyra, Laminaria, and Sargassum are examples of edible marine algae.
Brown and red algae yield hydrocolloids like algin and carrageen, used commercially.
Chlorella, a protein-rich unicellular alga, is used as a food supplement.
Algae are classified into three main groups: Chlorophyceae (green algae), Phaeophyceae (brown algae), and Rhodophyceae (red algae).

Chlorophyceae (Green Algae)

Green algae have unicellular, colonial, or filamentous forms.
They typically showcase a grass-green color due to the predominance of chlorophyll a and b.
Pigments are contained within defined chloroplasts, exhibiting various shapes.
Pyrenoids, storage bodies within chloroplasts, hold protein and starch.
Some species store food as oil droplets.
Cell walls are composed of an inner cellulose layer and an outer pectose layer.
Vegetative reproduction occurs through fragmentation or spore formation.
Asexual reproduction involves zoospores, produced in zoosporangia.
Sexual reproduction displays variations in sex cell types and formation, including isogamous, anisogamous, or oogamous processes.
Common examples include Chlamydomonas, Volvox, Ulothrix, Spirogyra, and Chara.

Phaeophyceae (Brown Algae)

Brown algae are primarily marine and exhibit variations in size and form.
They range from simple branched filaments to large, complex forms like kelps, reaching up to 100 meters in height.
Pigments include chlorophyll a, c, carotenoids, and xanthophylls.
Color varies from olive green to brown, depending on the amount of fucoxanthin, a specific xanthophyll pigment.
Asexual reproduction occurs through non-motile spores, while sexual reproduction involves non-motile gametes.
Sexual reproduction is oogamous, with complex post-fertilization development.
Common examples include Polysiphonia, Porphyra, Gracilaria, and Gelidium.

Bryophytes

Bryophytes, including mosses and liverworts, are often found in moist, shaded environments.
They are called "amphibians of the plant kingdom" due to their dependence on water for sexual reproduction.
Bryophytes play a crucial role in plant succession on bare soil or rocks.
The plant body is more differentiated than algae, being thallus-like and either prostrate or erect.
They lack true roots, stems, or leaves, but possess root-like (rhizoids), leaf-like, and stem-like structures.
The primary plant body is the gametophyte (haploid), which produces gametes.
Sex organs are multicellular: the male antheridium produces biflagellate antherozoids, while the female archegonium produces a single egg.
Antherozoids fuse with the egg in water, forming a zygote.
The zygote develops into a multicellular sporophyte, which remains attached to the gametophyte and relies on it for sustenance.
Spores produced through meiosis in the sporophyte are haploid and germinate into new gametophytes.

Algae: The Basis of Aquatic Life

Importance: Algae are crucial primary producers in aquatic ecosystems, using photosynthesis to generate energy-rich compounds and increase dissolved oxygen.
Food Source: 70 marine algae species are used as food, including Porphyra, Laminaria and Sargassum.
Hydrocolloid Production: Certain brown and red algae create commercial hydrocolloids like algin (from brown algae) and carrageen (from red algae), used in various industries.
Agar Production: Gelidium and Gracilaria produce agar, used for microbial growth cultivation and in food products like ice-cream and jellies.
Chlorella: This single-celled alga is rich in protein and serves as a food supplement, even for space travelers.

Chlorophyceae (Green Algae)

Characteristics: Green algae are generally grass green due to chlorophyll a and b dominance. They exist as unicellular, colonial or filamentous organisms.
Chloroplast Variation: Chloroplasts can take various forms, including discoid, plate-like, reticulate, cup-shaped, spiral or ribbon-shaped.
Pyrenoids: These storage bodies within chloroplasts store protein and starch.
Cell Wall: Composed of an inner cellulose layer and an outer pectose layer.
Reproduction:
- Vegetative: Fragmentation or spore formation.
- Asexual: Flagellated zoospores produced in zoosporangia.
- Sexual: Isogamous, anisogamous or oogamous, with varying sex cell types and formation.
Common Examples: Chlamydomonas, Volvox, Ulothrix, Spirogyra, and Chara.

Phaeophyceae (Brown Algae)

Habitat: Primarily found in marine environments.
Size and Form: Vary greatly, ranging from simple branched, filamentous forms (Ectocarpus) to the large kelps, reaching up to 100 meters in height.
Pigments: Possess chlorophyll a, c, carotenoids, and xanthophylls.
Color: Ranges from olive green to various shades of brown depending on the amount of fucoxanthin.
Food Storage: Store food as complex carbohydrates, including laminarin or mannitol.
Cell Wall: Cellulose wall with an external gelatinous algin coating.
Structure: Typically attached to a substrate with a holdfast, followed by a stipe (stalk) and frond (leaf-like photosynthetic organ).
Reproduction:
- Vegetative: Fragmentation.
- Asexual: Biflagellate, pear-shaped zoospores with two unequal, laterally attached flagella.
- Sexual: Isogamous, anisogamous, or oogamous; gametes are pear-shaped and biflagellate.
Common Examples: Ectocarpus, Dictyota, Laminaria, Sargassum, and Fucus

Rhodophyceae (Red Algae)

Characteristics: Predominantly red due to the presence of the pigment phycoerythrin. Most are marine with greater concentrations in warmer regions.
Habitat: Found in well-lit surface waters and deeper ocean depths.
Structure: Multicellular thalli with complex body organization.
Food Storage: Store food as floridean starch, similar in structure to amylopectin and glycogen.
Reproduction:
- Vegetative: Fragmentation.
- Asexual: Non-motile spores.
- Sexual: Oogamous, with non-motile gametes and complex post-fertilization development.
Common Examples: Polysiphonia, Porphyra, Gracilaria, and Gelidium.

Bryophytes (Mosses and Liverworts)

Habitat: Common in moist, shaded areas, particularly in hilly regions.
Dominant Phase: Gametophytic plant body.
Sporophyte Structure: Consists of a foot, seta (stalk), and capsule containing spores formed through meiosis.
Spore Dispersal: Mosses have a sophisticated spore dispersal mechanism.
Common Examples: Funaria, Polytrichum, and Sphagnum.

Pteridophytes (Ferns and Horsetails)

Importance: Used medicinally, as soil-binders, and as ornamentals.
Evolution: The first terrestrial plants to evolve vascular tissues (xylem and phloem).
Habitat: Cool, damp, shady areas, but some can thrive in sandy soil.
Dominant Phase: Sporophytic plant body.
Sporophyte Structure: Differentiated into true roots, stem, and leaves with well-developed vascular tissues.
Leaf Types: Microphylls (small, as in Selaginella) and macrophylls (large, as in ferns).
Sporangia: Borne on sporophylls, sometimes forming compact structures called strobili or cones (in Selaginella and Equisetum).
Spore Production: Produced by meiosis in spore mother cells.
Gametophyte: Small, inconspicuous, and free-living; called prothallus.
Reproduction:
- Gametophyte: Bears antheridia (male sex organs) and archegonia (female sex organs).
- Fertilization: Requires water for the transfer of antherozoids (male gametes).
- Zygote Development: Forms a multicellular, well-differentiated sporophyte.
Homosporous: Most pteridophytes produce only one type of spore.
Heterosporous: Some, like Selaginella and Salvinia, produce two types of spores: macro (large) and micro (small).
Important Evolutionary Step: The retention of female gametophytes on the parent sporophyte for a period is a precursor to the seed habit.
Classification: Four classes:
- Psilopsida (Psilotum)
- Lycopsida (Selaginella, Lycopodium)
- Sphenopsida (Equisetum)
- Pteropsida (Dryopteris, Pteris, Adiantum)

Gymnosperms (Conifers)

Definition: Plants with ovules that are not enclosed by an ovary wall and remain exposed before and after fertilization.
Seed Development: Seeds develop after fertilization and are not covered (naked).
Size and Form: Include medium-sized trees, tall trees, and shrubs.
Roots: Usually tap roots, with mycorrhiza fungal associations in some species (e.g., Pinus), and specialized coralloid roots associated with nitrogen-fixing cyanobacteria in others (e.g., Cycas).
Stems: Unbranched (Cycas) or branched (Pinus, Cedrus).
Leaves: Simple or compound; in Cycas, pinnate leaves persist for a few years.
Leaf Adaptations: Well-adapted to withstand extreme temperatures, humidity, and wind; needle-like leaves reduce surface area, and thick cuticles and sunken stomata help reduce water loss.
Reproduction:
- Heterosporous: Produce haploid microspores and megaspores.
- Evolution: An important evolutionary step towards the development of flowering plants.

Algae

Photosynthetic organisms that increase oxygen levels in their environment.
Primary producers of energy-rich compounds that form the basis of food cycles for aquatic animals.
Some species are used as food, such as Porphyra, Laminaria, and Sargassum.
Brown and red algae produce hydrocolloids like algin and carrageen, which are used commercially.
Agar, a product from Gelidium and Gracilaria, is used for growing microbes and in food products.
Chlorella, a unicellular alga rich in protein, is used as a food supplement.
Three main classes: Chlorophyceae (green algae), Phaeophyceae (brown algae), and Rhodophyceae (red algae).

Chlorophyceae

Commonly called green algae.
Can be unicellular, colonial, or filamentous.
Usually grass green due to chlorophyll a and b.
Chloroplasts can have different shapes: discoid, plate-like, reticulate, cup-shaped, spiral, or ribbon-shaped.
Contain pyrenoids, storage bodies that contain protein and starch.
Some store food as oil droplets.
Have a rigid cell wall with an inner cellulose layer and an outer pectose layer.
Vegetative reproduction occurs through fragmentation or spore formation.
Asexual reproduction occurs through flagellated zoospores produced in zoosporangia.
Sexual reproduction can be isogamous, anisogamous, or oogamous.
Common examples: Chlamydomonas, Volvox, Ulothrix, Spirogyra, and Chara.

Phaeophyceae

Commonly called brown algae.
Found primarily in marine habitats.
Vary in size and form, from simple branched filaments to large kelp forests reaching 100 meters in height.
Possess chlorophyll a, c, carotenoids, and xanthophylls.
Colour ranges from olive green to various shades of brown based on the amount of fucoxanthin.
Asexual reproduction occurs through non-motile spores.
Sexual reproduction is oogamous and involves complex post-fertilization developments.
Common examples: Polysiphonia, Porphyra, Gracilaria, and Gelidium.

Bryophytes

Include mosses and liverworts.
Found in moist, shaded areas.
Gametophytes bear male (antheridia) and female (archegonia) sex organs.
Water is needed for transferring antherozoids (male gametes) to the archegonia.
Fusion of male and female gametes forms a zygote, which produces a multicellular sporophyte.
Sporophyte is the dominant phase of bryophytes.
Most bryophytes are homosporous, producing spores of the same kind.
Heterosporous bryophytes, like Selaginella and Salvinia, produce macro (large) and micro (small) spores.

Pteridophytes

Include ferns and their allies.
Sporophyte is the dominant phase, with true roots, stems, and leaves.
Possess vascular tissues for transport.
Sporophyte bears sporangia, which produce spores.
Spores germinate into gametophytes, which require cool, damp environments to grow.
Gametophytes bear male and female sex organs.
Water is needed for transferring male gametes to the female gametophyte for fertilization.
Zygote produces a sporophyte.
Classified into four classes: Psilopsida (Psilotum), Lycopsida (Selaginella, Lycopodium), Sphenopsida (Equisetum), and Pteropsida (Dryopteris, Pteris, Adiantum).

Gymnosperms

"Naked seed" plants, where ovules are exposed before and after fertilization.
Include medium-sized trees, tall trees, and shrubs.
Roots are generally tap roots.
Some genera have fungal associations (mycorrhiza) while others have coralloid roots associated with nitrogen-fixing cyanobacteria.
Stems can be unbranched or branched.
Leaves can be simple or compound.
Leaves are well-adapted to withstand extreme temperatures, humidity, and wind.
Needle-like leaves in conifers reduce surface area, and thick cuticles and sunken stomata minimize water loss.
Heterosporous, producing microspores and megaspores within sporangia borne on sporophylls.
Sporophylls arranged in strobili or cones.
Microsporangiate (male) strobili produce microspores, which develop into pollen grains.
Macrosporangiate (female) strobili produce megaspores, which develop into female gametophytes.
Male and female cones may be on the same tree (Pinus) or different trees (Cycas).
Megaspore mother cell produces a megaspore that matures into a female gametophyte bearing archegonia (female sex organs).
Male and female gametophytes are dependent on the sporophyte.
Pollen grains released from microsporangia are carried by wind to the ovules, where they germinate and grow towards the archegonia.
Fertilization results in a zygote that develops into an embryo, forming a seed.
Seeds are not enclosed by an ovary.

Angiosperms

"Flowering plants" where ovules are enclosed in ovaries.
Pollen grains and ovules develop in flowers.
Seeds are enclosed within fruits.
Exceptionally large group with a wide range of habitats.
Range in size from small Wolffia to tall Eucalyptus trees.
Provide food, fodder, fuel, medicine, and other commercial products.
Divided into two classes: dicots (two cotyledons) and monocots (one cotyledon).

Algae

Algae are photosynthetic organisms that increase dissolved oxygen in their immediate environment.
They are primary producers of energy-rich compounds, forming the base of aquatic food cycles.
Some species of algae, such as Porphyra, Laminaria, and Sargassum, are used as food.
Marine brown and red algae produce hydrocolloids like algin and carrageen, which are used commercially.
Agar, a product from Gelidium and Gracilaria, is used for growing microbes and in food manufacturing.
Chlorella, a unicellular alga, is a rich protein source, even used by space travelers.

Chlorophyceae (Green Algae)

Green algae can be unicellular, colonial, or filamentous.
They are green due to chlorophyll a and b pigments.
Their chloroplasts can have different shapes, including discoid, plate-like, and spiral.
Pyrenoids, located in chloroplasts, store protein and starch.
Green algae have cell walls made of cellulose and pectose.
Vegetative reproduction occurs through fragmentation or spore formation.
Asexual reproduction involves flagellated zoospores produced in zoosporangia.
Sexual reproduction can be isogamous, anisogamous, or oogamous.
Common examples include Chlamydomonas, Volvox, Ulothrix, Spirogyra, and Chara.

Phaeophyceae (Brown Algae)

Brown algae are primarily marine.
They exhibit diverse sizes and forms, ranging from simple filamentous to large kelps.
They contain chlorophyll a, c, carotenoids, and xanthophylls, giving them an olive green to brown colour.
They store food as laminarin or mannitol.
Their cell walls are made of cellulose and covered in algin.
They have a holdfast for attachment, a stipe, and a frond for photosynthesis.
Vegetative reproduction happens through fragmentation.
Asexual reproduction involves biflagellate zoospores.
Sexual reproduction can be isogamous, anisogamous, or oogamous.
Common examples include Ectocarpus, Dictyota, Laminaria, Sargassum, and Fucus.

Rhodophyceae (Red Algae)

Red algae are named for their prominent red pigment, r-phycoerythrin.
They are primarily marine, found in shallower and deeper water.
Most are multicellular, with some having complex body structures.
They store food as floridean starch, similar to amylopectin and glycogen.
Vegetative reproduction occurs through fragmentation.
Red algae reproduce sexually through antheridia and archegonia, with fertilization occurring in water.

Bryophytes

Bryophytes are often called the “amphibians” of the plant kingdom.
They need water for sexual reproduction.
The plant body is thallus-like and can be prostrate or erect.
They lack true roots, stems, and leaves but have rhizoids for attachment.
The dominant stage is the haploid gametophyte.
Male sex organs (antheridia) produce biflagellate antherozoids.
The female sex organ (archegonium) produces a single egg.
Fertilization occurs in water, forming a diploid sporophyte dependent on the gametophyte.
Sporophyte undergoes meiosis to produce haploid spores.
Bryophytes have limited economic importance, but some provide food for animals or are used as fuel and packing material.
They play a vital role in plant succession and soil stabilization.

Liverworts

Liverworts thrive in damp, shady environments.
The plant body is a thallus (e.g., Marchantia).
Asexual reproduction occurs through fragmentation or gemmae.
Sexual reproduction involves male and female sex organs on the same or different thalli.
The sporophyte is differentiated into a foot, seta, and capsule.

Mosses

The gametophyte is the dominant stage in moss life cycles.
The gametophyte has two phases: a protonema (creeping, filamentous) and a leafy stage.
Leaves are spirally arranged on upright axes.
Vegetative reproduction occurs through fragmentation or budding in the protonema.
Sexual reproduction involves antheridia and archegonia at the apex of leafy shoots.
The sporophyte is more elaborate than in liverworts and consists of a foot, seta, and capsule.
Common moss examples include Funaria, Polytrichum, and Sphagnum.

Pteridophytes

Pteridophytes include horsetails and ferns.
They are used for medicinal purposes, soil binding, and ornamentals.
They are the first terrestrial plants to have vascular tissues (xylem and phloem).
They are found in cool, damp, shady places but can also thrive in sandy soils.
The dominant stage is the sporophyte, which is differentiated into true roots, stems, and leaves.
Leaves can be small (microphylls, e.g., Selaginella) or large (macrophylls, e.g., ferns).
Sporophytes bear sporangia, often subtended by leaf-like sporophylls.
In some cases, sporophylls form strobili or cones (e.g., Selaginella, Equisetum).
Sporangia produce spores through meiosis.
Spores germinate into inconspicuous, photosynthetic gametophytes called prothalli, which need cool, damp, shady environments to grow.
Limited spatial distribution due to specific requirements and need for water for fertilization.

Plant Kingdom Classification

The Five Kingdom classification was proposed by Whittaker in 1969 which included Monera, Protista, Fungi, Animalia and Plantae.
The Plant Kingdom has been redefined over time, excluding Fungi and members of the Monera and Protista.
The Plant Kingdom is now characterized by multicellular organisms with cell walls and chlorophyll for photosynthesis.
The Plant Kingdom is classified into the following groups:
Algae
Bryophytes
Pteridophytes
Gymnosperms
Angiosperms

Algae

Algae are classified into three main classes: Chlorophyceae, Phaeophyceae, and Rhodophyceae.

Chlorophyceae

Chlorophyceae are commonly known as green algae
They exhibit a variety of forms including unicellular, colonial, or filamentous.
They are typically grass-green due to the dominant pigments chlorophyll a and b.
Chloroplasts are present and may be discoid, plate-like, reticulate, cup-shaped, spiral, or ribbon-shaped.
Most species have one or more storage bodies called pyrenoids within the chloroplasts.
Pyrenoids contain protein and starch.
Cell walls are rigid and composed of an inner cellulose layer and an outer pectose layer.
Vegetative reproduction occurs through fragmentation or spore formation.
Asexual reproduction involves zoospores produced in zoosporangia.
Sexual reproduction exhibits various forms: isogamous, anisogamous, and oogamous.
Common examples of green algae include Chlamydomonas, Volvox, Ulothrix, Spirogyra, and Chara.

Phaeophyceae

Phaeophyceae refers to brown algae, primarily found in marine environments.
Brown algae show great variation in size and form, ranging from simple branched filaments to complex forms like the kelps, which can reach up to 100 meters in height.
They contain chlorophyll a, c, carotenoids, and xanthophylls.
Their color varies from olive green to shades of brown, depending on the amount of fucoxanthin present.

Rhodophyceae

Rhodophyceae are commonly known as red algae, typically found in marine environments.
They are known for their distinctive red color, due to the presence of pigments such as phycoerythrin and chlorophyll.
They have a complex life cycle and play a vital role in coral reefs.

Bryophytes

Bryophytes are also known as amphibians of the plant kingdom.
They can live in soil but depend on water for sexual reproduction.
Bryophytes are typically found in damp, humid, and shaded locations.
They contribute to plant succession on bare rocks or soil.
The plant body of bryophytes is more differentiated than algae and can be thallus-like, prostrate, or erect, attached to the substratum by rhizoids.
Bryophytes lack true roots, stems, and leaves.

Pteridophytes

Pteridophytes include horsetails and ferns, often used for medicinal purposes, soil binding, and ornamental purposes.
Evolutionarily, they were the first terrestrial plants to possess vascular tissues - xylem and phloem.
Pteridophytes are typically found in cool, damp, and shady environments, although some can thrive in sandy-soil conditions.
The dominant phase in the life cycle of pteridophytes is the sporophyte, which is differentiated into true roots, stems, and leaves.
The sporophyte bears sporangia, subtended by leaf-like appendages called sporophylls.
Sporophylls can form distinct compact structures called strobili or cones.
The sporangia produce spores through meiosis in spore mother cells.
The spores germinate to form inconspicuous, small, multicellular, free-living, and predominantly photosynthetic thalloid gametophytes called prothallus.

Gymnosperms

Gymnosperms are plants with ovules not enclosed by any ovary wall.
Seeds are exposed, hence the name "naked-seeded plants."
Gymnosperms produce microspores and megaspores in microsporangia and megasporangia, respectively, borne on sporophylls.
Sporophylls, microsporophylls and megasporophylls, are arranged spirally on an axis to form male and female cones, respectively.
Pollen grains germinate releasing male gametes via the pollen tube into the ovule, where they fuse with the egg cell in archegonia.
After fertilization, the zygote develops into an embryo, and the ovule matures into a seed.
Common examples of gymnosperms are: Pines, Firs, Spruces, Cycads, and Ginkgoes.

Angiosperms

Angiosperms, also known as flowering plants, are the most diverse and successful group of plants.
Angiosperms produce their seeds within a protective ovary.
They are characterized by flowers, fruits, and a double fertilization process.
Angiosperms are further divided into two classes: Dicotyledons (dicots) and Monocotyledons (monocots).

Dicotyledons (Dicots)

Dicotyledons have two cotyledons (seed leaves) in their embryos.
Their vascular tissues are arranged in a ring, and their leaves typically have a net-like vein pattern.
Examples: roses, sunflowers, and beans.

Monocotyledons (Monocots)

Monocotyledons have one cotyledon in their embryos.
Vascular bundles are scattered throughout their stems, and their leaves usually have parallel veins.
Examples: grasses, lilies, and orchids.

Plant Kingdom Classification

The Plant Kingdom has evolved over time: Fungi, Monera, and Protista with cell walls are no longer included in the Plant Kingdom, despite previous classifications.
The Plant Kingdom consists of: Algae, Bryophytes, Pteridophytes, Gymnosperms, and Angiosperms.

Algae

Algae are classified into three main classes: Chlorophyceae (green algae), Phaeophyceae (brown algae), and Rhodophyceae (red algae).
Green algae are found in a variety of habitats, including freshwater, saltwater, and soil.
Brown algae are primarily marine and can be very large, reaching up to 100 meters in height.
Red algae are also mostly marine and have a variety of forms, including filamentous, branched, and sheet-like.

Bryophytes

Bryophytes are non-vascular plants, meaning they lack specialized tissues for transporting water and nutrients.
Bryophytes are typically small and inconspicuous, growing in moist, shady environments.
Bryophytes have a dominant gametophyte generation, meaning the haploid stage of the life cycle is the most prominent.
Bryophytes include Liverworts and Mosses.

Pteridophytes

Pteridophytes are vascular plants, meaning they have specialized tissues for transporting water and nutrients.
Pteridophytes are typically found in moist, shady environments.
Pteridophytes have a dominant sporophyte generation, meaning the diploid stage of the life cycle is the most prominent.
Pteridophytes include ferns, horsetails, and clubmosses.

Gymnosperms

Gymnosperms are seed-bearing plants, but unlike angiosperms, their seeds are not enclosed within an ovary.
Gymnosperms are typically found in a variety of habitats, including dry, cold, and temperate regions.
Gymnosperms include conifers, cycads, ginkgoes, and gnetophytes.

Angiosperms

Angiosperms are seed-bearing plants that have flowers and fruits.
Angiosperms are the most diverse group of plants, with over 250,000 species.
Angiosperms are typically found in a variety of habitats worldwide.
Angiosperms are divided into two classes: Monocotyledons and Dicotyledons.

Plant Kingdom

Plant kingdom classification has changed over time
Plants are divided into 5 kingdoms - Monera, Protista, Fungi, Animalia, and Plantae
Early classification for flowering plants used superficial morphological characters such as habit, colour, number and shape of leaves, etc. (Linnaeus)
Natural classification systems consider both internal and external features, such as ultra-structure, anatomy, embryology, and phytochemistry (Bentham and Hooker)
Phylogenetic classification considers evolutionary relationships between organisms.
Numerical taxonomy uses computer analysis and assigns numbers and codes to all observable characteristics.
Cytotaxonomy is based on cytological information such as chromosome number, structure and behaviour.
Chemotaxonomy uses chemical constituents of the plant to identify relationships.

Algae

Algae are simple, thalloid, chlorophyll-bearing, autotrophic and largely aquatic organisms
They occur in diverse environments, including moist stones, soils, and wood
Algae have variable forms and sizes, from colonial forms like Volvox and filamentous forms like Ulothrix and Spirogyra to massive plant bodies like kelps
Algae reproduce by vegetative, asexual, and sexual methods
Vegetative reproduction occurs via fragmentation, where each fragment develops into a thallus
Asexual reproduction occurs via the production of various spores, most commonly zoospores
Zoospores are flagellated (motile) and germinate to form new plants
Sexual reproduction occurs through the fusion of two gametes, which can be flagellated and similar in size (isogamous), dissimilar in size (anisogamous), or one large and non-motile and the other smaller and motile (oogamous)

Bryophytes

Bryophytes are called the amphibians of the plant kingdom because they live in soil but need water for sexual reproduction.
Bryophytes typically occur in damp, humid, and shaded locations
They play a significant role in plant succession, establishing on bare rocks and soil surfaces
The plant body of bryophytes is more differentiated than algae and can be thallus-like, prostrate, or erect, with rhizoids attaching them to the substrate
Bryophytes lack true roots, stems, or leaves but may have root-like, leaf-like, or stem-like structures
The dominant phase of the bryophyte life cycle is the haploid gametophyte, which produces gametes
Male sex organs (antheridia) produce biflagellate antherozoids, while female sex organs (archegonia) produce a single egg
Antherozoids are released into water, where they fuse with an egg to produce a diploid zygote
The zygote develops into a multicellular, non-free-living sporophyte, which is attached to the gametophyte and derives nourishment from it
Sporophytes undergo meiosis to produce haploid spores, which germinate to produce gametophytes

Pteridophytes

Pteridophytes are the first terrestrial vascular plants
They require water for sexual reproduction
The dominant phase of the pteridophyte life cycle is the diploid sporophyte
The plant body is differentiated into roots, stem, and leaves
Vascular tissues transport water and nutrients throughout the plant
The sporophyte produces spores, which germinate to form haploid, free-living gametophytes called prothalli
Prothalli bear antheridia and archegonia
Antherozoids released from antheridia fuse with eggs in the archegonia, forming a zygote
The zygote develops into a diploid sporophyte
Pteridophytes can be homosporous (producing one type of spore) or heterosporous (producing two types of spores)
Heterosporous species, like Selaginella and Salvinia, produce megaspores (large) and microspores (small), which develop into female and male gametophytes, respectively
The female gametophyte is retained on the parent sporophyte, and the zygote develops into an embryo within the female gametophyte, marking a precursor to the evolution of the seed habit

Gymnosperms

Gymnosperms produce naked seeds.
Ovules are not enclosed by an ovary wall.
Gymnosperms include tall trees, shrubs, and medium-sized trees including the giant redwood Sequoia, one of the tallest tree species.
They have tap roots, with some species having fungal associations (mycorrhiza) or specialized roots associated with nitrogen-fixing cyanobacteria (coralloid roots).
Gymnosperms have branched or unbranched stems and well-adapted leaves for withstanding extreme conditions
Gymnosperms are heterosporous and produce microspores and megaspores
Microsporophylls and megasporophylls form male and female cones, respectively.
Pollen grains from male cones germinate and release male gametes into the ovule, where they fertilize the egg cell.
The fertilized egg develops into an embryo, and the ovule develops into a seed.

Angiosperms

Angiosperms are the flowering plants and produce seeds enclosed within an ovary.
They are divided into two classes – dicotyledons and monocotyledons.

Plant Kingdom

Plant kingdom includes algae, bryophytes, pteridophytes, gymnosperms and angiosperms
Early classification systems used superficial morphological characteristics
These systems were artificial and did not reflect natural affinities
Natural classification systems consider external and internal features like anatomy, embryology, and phytochemistry
Phylogenetic classification systems are based on evolutionary relationships
Numerical taxonomy utilizes computer analysis of observable characteristics
Cytotaxonomy focuses on cytological information like chromosome number
Chemotaxonomy uses chemical constituents of the plant for classification

Algae

Chlorophyll-bearing, simple, thalloid organisms
Mostly aquatic, found in fresh water and marine habitats
Occur in moist stones, soils, and wood
Some forms associate with fungi (lichen) and animals
Form and size vary, ranging from colonial forms like Volvox to filamentous forms like Ulothrix and Spirogyra
Marine kelps can form massive plant bodies
Reproduce through vegetative (fragmentation), asexual (spore production), and sexual methods
Sexual reproduction can be isogamous (similar gametes), anisogamous (dissimilar gametes), or oogamous (one large, non-motile female gamete and a smaller, motile male gamete)
Algae are essential for carbon dioxide fixation and oxygen production
Many species are used as food
Commercial products obtained from algae include algin, carrageen, and agar
Classified into three main classes: Chlorophyceae (green algae), Phaeophyceae (brown algae), and Rhodophyceae (red algae)

Chlorophyceae (Green Algae)

Unicellular, colonial, or filamentous
Grass green due to chlorophyll a and b
Chloroplasts have diverse shapes
Contain pyrenoids for starch storage
Store food in oil droplets
Have rigid cell walls made of cellulose and pectose
Vegetative reproduction by fragmentation or spore formation
Asexual reproduction by flagellated zoospores
Sexual reproduction is isogamous, anisogamous, or oogamous
Common examples are Chlamydomonas, Volvox, Ulothrix, Spirogyra, and Chara

Phaeophyceae (Brown Algae)

Primarily marine
Varied in size and form, from filamentous to massive kelps
Possess chlorophyll a, c, carotenoids, and xanthophylls
Colour ranges from olive green to brown depending on the amount of fucoxanthin
Store food as laminarin and mannitol
Reproduce through vegetative, asexual, and sexual methods
Common examples are Ectocarpus, Laminaria, and Fucus

Rhodophyceae (Red Algae)

Mainly marine, can also be found in fresh water
Have chlorophyll a, d, and phycobilins (red pigments)
Store food as floridean starch
Cell walls are composed of cellulose and a gelatinous substance
Reproduce through vegetative, asexual, and sexual methods
Common examples are Porphyra, Gelidium, and Gracilaria

Bryophytes

Amphibious plants, require moisture for reproduction
Have a dominant gametophyte phase
Gametophyte is differentiated into thallus (liverworts) or leafy shoots (mosses)
Lack vascular tissue
Anchored to the substrate by rhizoids
Reproduce through asexual (fragmentation, gemmae) and sexual methods
Sporophyte dependent on gametophyte
Classified into liverworts and mosses

Liverworts

Thalloid or leafy
Thallus is dorsiventral and closely appressed to the substrate
Asexual reproduction by fragmentation or gemmae formation
Sexual reproduction occurs on the same or different thalli
Sporophyte is differentiated into foot, seta, and capsule

Mosses

Leafy gametophyte with two stages: protonema (filamentous) and leafy stage
Leafy stage has upright, slender axes with spirally arranged leaves
Vegetative reproduction by fragmentation and budding
Sexual reproduction takes place at the apex of the leafy shoots
Sporophyte is dependent on the gametophyte

Pteridophytes

Vascular plants with a dominant sporophyte phase
Have true roots, stems, and leaves
Possess vascular tissue (xylem and phloem)
Reproduce through spores produced in sporangia
Sporangia are clustered together in sori on the underside of leaves
Life cycle includes an independent, multicellular gametophyte called prothallus
Examples are ferns, horsetails, and clubmosses

Gymnosperms

Naked-seeded plants
Have a dominant sporophyte phase
Produce microspores and megaspores in microsporangia and megasporangia
Sporophylls are arranged spirally to form cones
Pollination takes place by wind
Fertilization occurs inside the ovule, resulting in a seed
Examples are pines, cycads, and conifers

Angiosperms

Flowering plants with seeds enclosed within an ovary wall
Dominant sporophyte phase
Possess flowers for sexual reproduction
Fruits develop from the ovary wall and protect the seeds
Divided into two classes: Monocotyledons and Dicotyledons

Monocotyledons

Have one cotyledon in the seed
Parallel venation in leaves
Fibrous root system
Floral parts are in multiples of three
Examples are grasses, lilies, palms, and orchids

Dicotyledons

Have two cotyledons in the seed
Reticulate venation in leaves
Taproot system
Floral parts are in multiples of four or five
Examples are beans, peas, sunflowers, and roses

Algae

Algae are photosynthetic and increase dissolved oxygen in their environment
They are primary producers of energy-rich compounds for aquatic food chains
70 species of algae are used as food, such as Porphyra, Laminaria, and Sargassum
Marine brown and red algae produce hydrocolloids (algin & carrageen) used commercially
Chlorella, a unicellular alga, is high in protein and used by space travelers
Algae are classified into Chlorophyceae, Phaeophyceae, and Rhodophyceae

Chlorophyceae (Green Algae)

Plant body can be unicellular, colonial, or filamentous
Usually grass green due to chlorophyll a and b dominance
Chloroplasts vary in shape (discoid, plate-like, reticulate, cup-shaped, spiral, ribbon-shaped)
Contain pyrenoids in chloroplasts for starch and protein storage
Some store food as oil droplets
Cell wall has an inner cellulose layer and outer pectose layer
Vegetative reproduction by fragmentation or spore formation
Asexual reproduction by flagellated zoospores
Sexual reproduction can be isogamous, anisogamous, or oogamous
Common examples include Chlamydomonas, Volvox, Ulothrix, Spirogyra, and Chara

Phaeophyceae (Brown Algae)

Mostly found in marine environments
Vary in size and form from simple filamentous to large kelps reaching 100 meters
Possess chlorophyll a, c, carotenoids, and xanthophylls (fucoxanthin)
Color varies from olive green to brown depending on fucoxanthin concentration
Food storage is as complex carbohydrates like laminarin or mannitol
Vegetative cells have a cellulose wall with a gelatinous algin coating
Plant body attached to substrate by a holdfast, with a stipe (stalk) and frond (leaf-like)
Vegetative reproduction by fragmentation
Asexual reproduction by biflagellate, pear-shaped zoospores
Sexual reproduction can be isogamous, anisogamous, or oogamous
Common examples include Ectocarpus, Dictyota, Laminaria, Sargassum, and Fucus

Rhodophyceae (Red Algae)

Primarily red due to predominance of r-phycoerythrin pigment
Mostly marine, concentrated in warmer regions
Found close to the surface and at great depths
Thallium (plant body) is multicellular in most species
Some have complex body organization
Food storage as floridean starch, similar to amylopectin and glycogen
Vegetative reproduction by fragmentation

Bryophytes

Bryophytes are divided into liverworts and mosses
Of little economic importance; some mosses provide food for animals
Sphagnum moss provides peat used as fuel and packing material
Mosses and lichens are pioneers colonizing rocks, important for ecological succession
Decompose rocks, make substrate suitable for higher plants
Dense mats reduce rainwater impact and prevent soil erosion

Liverworts

Grow in moist, shady habitats like stream banks and tree bark
Plant body is thalloid (e.g., Marchantia), flattened and attached to the substrate
Leafy members have small leaf-like appendages
Asexual reproduction by fragmentation or gemmae formation
Gemmae are multicellular buds in gemma cups that detach and form new individuals
Sexual reproduction has male and female sex organs on the same or different thalli
Sporophyte has foot, seta, and capsule
Spores produced by meiosis and germinate into free-living gametophytes

Mosses

Gametophyte is the dominant stage, in two stages:
- Protonema: creeping filamentous stage, developing from a spore
- Leafy stage: upright, with spirally arranged leaves, develops from a secondary protonema
Rhizoids anchor the plant to the soil
Vegetative reproduction by fragmentation and budding
Sexual reproduction with antheridia (male) and archegonia (female) on leafy shoots
Sporophyte develops after fertilization, consisting of foot, seta, and capsule
Sporophyte more elaborate than in liverworts
Spores formed by meiosis and dispersed
Common examples include Funaria, Polytrichum, and Sphagnum

Pteridophytes (Ferns & Horsetails)

Used medicinally, as soil-binders, and ornamentals
First terrestrial plants to possess vascular tissues (xylem & phloem)
Found in cool, damp, shady places, some tolerate sandy conditions
Sporophyte is dominant, with true root, stem, and leaves (Figure 3.3)
Leaves can be small (microphylls, Selaginella) or large (macrophylls, ferns)
Sporophylls (leaf-like appendages) subtend sporangia
Some have strobili or cones (Selaginella, Equisetum)
Sporangia produce spores by meiosis
Spores germinate into prothallus (small, photosynthetic gametophyte)
Gametophytes require specific conditions and water for fertilization
Antheridia (male) and archegonia (female) on the gametophyte
Water required for antherozoids (male gametes) to reach archegonium
Zygote forms after fertilization, developing into a sporophyte
Most pteridophytes are homosporous (produce one type of spore)
Selaginella and Salvinia are heterosporous (produce macro & micro spores)
Megaspores and microspores become female and male gametophytes respectively
Female gametophytes retained on parent sporophyte
Embryos develop within female gametophytes, precursor to the seed habit
Classified into Psilopsida, Lycopsida, Sphenopsida, and Pteropsida

Gymnosperms

Ovules not enclosed by ovary wall, remain exposed (naked seeds)
Include trees, shrubs, and the tallest tree species, Sequoia
Roots are tap roots
Some have mycorrhizae (Pinus) or coralloid roots (Cycas) associated with N2-fixing cyanobacteria
Stems can be unbranched (Cycas) or branched (Pinus, Cedrus)
Leaves can be simple or compound
Leaves adapted to withstand extreme conditions, needle-like leaves reduce surface area, thick cuticle and sunken stomata minimize water loss
Heterosporous, producing microspores and megaspores

Plant Kingdom

Plant Kingdom includes algae, bryophytes, pteridophytes, gymnosperms, and angiosperms.
Earlier classifications included fungi, Monera, and Protista as part of the Plantae kingdom.
Cyanobacteria, previously called blue-green algae, are not considered algae anymore.

Algae

Unicellular, colonial, or filamentous organisms.
Primarily aquatic.
Classified into three main classes: Chlorophyceae, Phaeophyceae, and Rhodophyceae.
Contain chlorophyll a and b, giving them a grass-green color.
Store food as starch, oil droplets, or complex carbohydrates.
Have a rigid cell wall made of cellulose and pectose.
Reproduce asexually by fragmentation, zoosporangia, or spores, and sexually through isogamy, anisogamy, or oogamy.
Examples include Chlamydomonas, Volvox, Ulothrix, Spirogyra, and Chara.

Chlorophyceae

Commonly known as green algae.
Have chloroplasts that can be discoid, plate-like, reticulate, cup-shaped, spiral, or ribbon-shaped.
Contain pyrenoids within chloroplasts, which store protein and starch.

Phaeophyceae

Commonly known as brown algae.
Primarily found in marine habitats.
Show great variation in size and form, ranging from simple to complex branched structures.
Possess chlorophyll a, c, carotenoids, and xanthophylls.
Color varies from olive green to brown depending on the amount of the pigment fucoxanthin.
Store food as laminarin or mannitol.
Have a cellulosic wall covered with a gelatinous coating of algin.
Reproduce vegetatively by fragmentation, asexually by biflagellate zoospores, and sexually by isogamy, anisogamy, or oogamy.
Common examples include Ectocarpus, Dictyota, Laminaria, Sargassum, and Fucus.

Rhodophyceae

Commonly known as red algae.
Predominantly marine, with higher concentrations in warmer areas.
Have a red color due to the pigment r-phycoerythrin.
Multicellular with complex body organization.
Store food as floridean starch.
Reproduce vegetatively by fragmentation, and sexually with antheridia and archegonia.
Water is essential for transfer of antherozoids (male gametes) to the archegonium.
Zygote develops into a multicellular sporophyte, the dominant phase in the life cycle.

Bryophytes

Live in soil but depend on water for sexual reproduction.
Thallus-like plant body, may be prostrate or erect.
Attached to the substratum by rhizoids.
Possess root-like, leaf-like, and stem-like structures.
Divided into liverworts and mosses.
Liverworts have a thalloid, dorsiventral plant body.
Mosses have upright, slender axes with spirally arranged leaves.
The main plant body of a bryophyte is the gametophyte, which produces gametes.
Gametophytes bear antheridia (male) and archegonia (female).
Fusion of gametes creates a zygote, which produces a multicellular sporophyte.
Sporophytes produce haploid spores, which germinate to form gametophytes.

Pteridophytes

The main plant body is a sporophyte, differentiated into true roots, stems, and leaves.
Possess vascular tissues.
Sporophytes bear sporangia, which produce spores.
Spores germinate to form gametophytes, which require a cool, damp environment.
Gametophytes bear antheridia (male) and archegonia (female).
Water is required for transfer of male gametes to archegonia, where fertilization occurs.
The zygote produces a sporophyte.
Divided into four classes: Psilopsida, Lycopsida, Sphenopsida, and Pteropsida.
Mostly homosporous (produce one type of spore), but Selaginella and Salvinia are heterosporous (produce two types of spores – macro and micro).
Heterosporous plants produce female and male gametophytes.
Female gametophytes are retained on the parent sporophyte.
The development of zygotes into embryos occurs within the female gametophytes.

Gymnosperms

"Naked seeds" as ovules remain exposed before and after fertilization.
Includes medium-sized trees, tall trees, and shrubs.
Have tap roots and may have mycorrhiza (fungal association) or coralloid roots (associated with N2-fixing cyanobacteria).
Stems may be unbranched or branched.
Leaves may be simple or compound.
Leaves are well-adapted to withstand extreme temperatures, humidity, and wind.
Conifers have needle-like leaves, thick cuticles, and sunken stomata to reduce water loss.
Heterosporous, producing haploid microspores and megaspores.

Angiosperms

"Flowering plants" with ovules enclosed within ovary walls.
Largest group of plants with wide habitat range.
Provide food, fodder, fuel, medicines, and various commercial products.
Divided into two classes: dicotyledons and monocotyledons.

Plant Kingdom

Plant Kingdom classification encompasses Algae, Bryophytes, Pteridophytes, Gymnosperms, and Angiosperms.
Fungi, Monera, and Protista are no longer classified within the Plant Kingdom.
Early classification systems relied heavily on external characteristics like habit, color, and leaf morphology.
These systems were considered "artificial" as they were based on a few characteristics, separating closely related species.
Natural classification systems emerged, taking into account internal features like anatomy, embryology, and phytochemistry.
Current accepted systems are phylogenetic, emphasizing evolutionary relationships between organisms.
Numerical taxonomy analyzes large datasets of observable characteristics to reveal relationships.
Cytotaxonomy considers chromosomal information and chemotaxonomy analyzes chemical constituents for classification.

Algae

Algae are chlorophyll-bearing, simple, thalloid, autotrophic organisms primarily found in aquatic environments.
Algae exhibit diverse forms ranging from colonial forms like Volvox to filamentous forms like Ulothrix and Spirogyra.
Some marine algae, such as kelps, form massive plant bodies.
Algae reproduce through vegetative (fragmentation), asexual (spore production, e.g., zoospores), and sexual methods (isogamy, anisogamy, oogamy).
Algae play a significant role in carbon dioxide fixation on Earth.

Bryophytes

Bryophytes are often called the "amphibians of the plant kingdom" due to their dependence on water for reproduction.
Bryophytes inhabit damp, humid, and shaded areas and contribute to plant succession.
The plant body is undifferentiated and lacks true roots, stems, or leaves.
The dominant generation in bryophytes is the haploid gametophyte.
Bryophytes possess multicellular sex organs: antheridia (male) produce biflagellate antherozoids and archegonia (female) produce a single egg.
Fertilization occurs in water, producing a zygote that develops into a non-free-living sporophyte attached to the gametophyte.
The sporophyte produces spores by meiosis, which germinate into gametophytes.
Common examples include Funaria, Polytrichum, and Sphagnum.

Pteridophytes

Pteridophytes include horsetails and ferns, often used medicinally, as soil binders, and ornamentals.
Pteridophytes are the first terrestrial plants to possess vascular tissues (xylem and phloem).
They thrive in cool, damp, shaded environments but some can adapt to sandy soils.
The dominant generation in pteridophytes is the sporophyte, which is differentiated into true roots, stem, and leaves.
Leaves can be either small (microphylls, like Selaginella) or large (macrophylls, like ferns).
Sporangia, borne on sporophylls, produce spores by meiosis.
Spores germinate into inconspicuous, free-living, photosynthetic gametophytes called prothalli.
Pteridophytes require specific environmental conditions for reproduction, limiting their geographic distribution.

Gymnosperms

Gymnosperms include cycads, conifers, and ginkgoes.
Gymnosperms produce two types of spores: microspores and megaspores.
Microspores form within microsporangia, borne on microsporophylls, and develop into pollen grains.
Megaspores develop within megasporangia, borne on megasporophylls, and form female gametophytes within ovules.
Unlike bryophytes and pteridophytes, gametophytes in gymnosperms are not free-living.
Pollen grains are dispersed by wind and reach ovules, where a pollen tube grows toward the archegonia, transporting male gametes.
Fertilization results in a zygote that develops into an embryo, and the ovule matures into a seed.

Angiosperms

Angiosperms, or flowering plants, produce flowers where pollen grains and ovules are developed.
Seeds are enclosed within fruits.

Plant Kingdom

Whittaker (1969) proposed Five Kingdom classification: Monera, Protista, Fungi, Animalia and Plantae.
Plant kingdom includes algae, bryophytes, pteridophytes, gymnosperms and angiosperms.
Fungi, members of Monera and Protista with cell walls were previously included in Plantae but have since been excluded.
Cyanobacteria, previously known as blue-green algae, are not algae.

Classification Systems

Early classification systems were artificial and based on superficial morphological characters, like habit, color, leaf shape, etc.
Artificial systems used vegetative characters and androecium structure, which isn't ideal because vegetative characters are easily affected by the environment.
Natural classification systems were developed based on natural affinities considering both external and internal features, including ultra-structure, anatomy, embryology, and phytochemistry.
George Bentham and Joseph Dalton Hooker developed a natural classification system for flowering plants.
Phylogenetic classification systems are acceptable, assuming taxa within the same group share a common ancestor.
Numerical Taxonomy uses computers to analyze all observable characteristics with equal importance.
Cytotaxonomy uses cytological information like chromosome number, structure, and behavior.
Chemotaxonomy utilizes the chemical constituents of the plant.

Algae

Algae are chlorophyll-bearing, simple, thalloid, autotrophic, and largely aquatic organisms.
They can also live on moist stones, soils, wood and in association with fungi (lichen) and animals.
Algae have variable form and size, ranging from colonial forms (Volvox) to filamentous forms (Ulothrix, Spirogyra) to massive plant bodies (kelps).
Reproduction in algae occurs through vegetative, asexual, and sexual methods.
Vegetative reproduction happens via fragmentation.
Asexual reproduction occurs through the production of spores, with zoospores being the most common.
Zoospores are flagellated (motile) and can germinate into new plants.
Sexual reproduction involves the fusion of two gametes.
Isogamous reproduction involves the fusion of two flagellated, similar-sized gametes.
Anisogamous reproduction involves the fusion of two gametes that differ in size.
Oogamous reproduction involves the fusion of a large, non-motile (static) female gamete and a smaller, motile male gamete.

Chlorophyceae (Green Algae)

They have chlorophyll a and b.
Food is stored as starch.
Cell walls are made of cellulose.
Flagella are 2-8, equal, and apical.
Found in freshwater, brackish water, and saltwater.

Phaeophyceae (Brown Algae)

They have chlorophyll a, c, and fucoxanthin.
Food is stored as mannitol and laminarin.
Cell walls are made of cellulose and algin.
Flagella are 2, unequal, and lateral.
Found in freshwater (rare), brackish water, and saltwater.

Rhodophyceae (Red Algae)

They have chlorophyll a, d, and phycoerythrin.
Food is stored as floridean starch.
Cell walls are made of cellulose, pectin, and polysulphate esters.
Flagella are absent.
Found in freshwater (some), brackish water, and saltwater (most).

Bryophytes

Bryophytes include mosses and liverworts.
They commonly grow in moist, shaded areas.
Bryophytes can live in soil but require water for sexual reproduction.
The bryophyte plant body is more differentiated than algae.
They have thallus-like forms and may be prostrate or erect, attached to the substratum by rhizoids.
Bryophytes possess root-like, leaf-like, and stem-like structures.
Bryophytes are divided into liverworts and mosses.
Liverworts have a thalloid, dorsiventral plant body.
Mosses have upright, slender axes with leaves arranged spirally.

Bryophyte Reproduction

The main bryophyte plant body is a gametophyte, responsible for producing gametes.
Gametophytes bear antheridia (male sex organs) and archegonia (female sex organs).
Male and female gametes fuse to form a zygote, which produces a multicellular sporophyte.
The sporophyte produces haploid spores.
Spores germinate to form gametophytes.

Pteridophytes

Pteridophytes are referred to as ferns and their allies.
They have a vascular system and are differentiated into true roots, stems, and leaves.
The sporophyte is the dominant generation in the life cycle.
Sporophytes bear sporangia that produce spores.
Spores germinate to form gametophytes, which require cool, damp environments.
Gametophytes produce antheridia and archegonia.
Water is needed for the transfer of male gametes to the archegonia for fertilization.
The zygote produces a sporophyte.

Angiosperms

Angiosperms are flowering plants and include a wide range of sizes, from the smallest Wolffia to tall trees like Eucalyptus.
They provide food, fodder, fuel, medicines, and other important products.
Angiosperms are divided into two classes: dicotyledons and monocotyledons.
Dicotyledons have two cotyledons in their seeds.
Monocotyledons have one cotyledon in their seeds.

Classification of Organisms

Taxonomic classification assumes organisms belonging to the same taxa share a common ancestor.
Modern classification relies on various sources, including fossil evidence, numerical taxonomy, cytotaxonomy, and chemotaxonomy.
Numerical taxonomy uses observable characteristics with assigned numbers and codes to analyze data.
Cytotaxonomy utilizes cytological information like chromosome number, structure, and behavior, while chemotaxonomy analyzes a plant's chemical constituents.

Algae

Algae are simple thalloid organisms with chlorophyll, predominantly found in aquatic environments like fresh water and marine habitats.
They exhibit diverse forms and sizes, ranging from colonial (e.g., Volvox) to filamentous (e.g., Ulothrix and Spirogyra) to massive plant bodies (e.g., kelps).
Algae reproduce through vegetative, asexual, and sexual methods.
Vegetative reproduction occurs through fragmentation where each fragment develops into a thallus.
Asexual reproduction involves the production of spores, predominantly zoospores, which are flagellated and motile.
Sexual reproduction occurs through the fusion of two gametes, which can be flagellated and similar in size (isogamous) or dissimilar in size (anisogamous).
Oogamous reproduction involves the fusion of a large, non-motile female gamete with a smaller, motile male gamete.

Uses of Algae

Algae play a significant role in carbon dioxide fixation, contributing to a significant portion of global carbon dioxide fixation through photosynthesis.
They enhance dissolved oxygen levels in their immediate environment, acting as crucial primary producers of energy-rich compounds within aquatic food cycles.
Certain algae, like Porphyra, Laminaria, and Sargassum, are used as food sources.
Marine brown and red algae produce hydrocolloids (water-holding substances), such as algin from brown algae and carrageen from red algae, utilized commercially.
Agar, a product from Gelidium and Gracilaria, is used in microbial growth and food products like ice cream and jellies.
Chlorella, a unicellular alga rich in protein, serves as a food supplement, even for space travelers.

Classes of Algae

Algae are categorized into three main classes: Chlorophyceae, Phaeophyceae, and Rhodophyceae.

Chlorophyceae

Chlorophyceae, commonly known as green algae, exhibit diverse forms, including unicellular, colonial, and filamentous.
Their green color stems from the dominance of chlorophyll a and b pigments.
Chloroplasts, containing the pigments, exhibit varying shapes like discoid, plate-like, reticulate, cup-shaped, spiral, or ribbon-shaped.
Many green algae possess pyrenoids within chloroplasts, acting as storage bodies for protein and starch, while others store food as oil droplets.

Phaeophyceae

Phaeophyceae, or brown algae, are primarily found in marine habitats.
They display a wide range of sizes and forms, from simple branched filaments (e.g., Ectocarpus) to extensively branched kelps reaching up to 100 meters.
Brown algae contain chlorophyll a, c, carotenoids, and xanthophylls.
Their coloration ranges from olive green to brown shades, depending on fucoxanthin, a xanthophyll pigment.

Bryophytes

Bryophytes are non-vascular plants, typically found in damp, shady environments like stream banks, marshy grounds, and on tree bark.
They play a crucial role in colonizing rocks and soil, contributing to the decomposition of rocks, making the substrate suitable for higher plants.
Bryophytes help prevent soil erosion by forming dense mats.
Bryophytes are broadly classified into two groups: liverworts and mosses.

Liverworts

Liverworts prefer moist, shady habitats.
The plant body of a liverwort is thalloid, like Marchantia.
Thalli are dorsoventral and closely attached to the substrate.
Leafy liverworts have small leaf-like appendages in two rows on stem-like structures.
Asexual reproduction occurs through fragmentation of thalli or specialized structures called gemmae.
Gemmae are green, multicellular, asexual buds that develop in gemma cups on the thalli.

Mosses

Mosses are the dominant stage of the life cycle.
The gametophyte of a moss undergoes two stages: protonema and leafy stage.
The protonema stage is creeping, green, branched, and filamentous.
The leafy stage arises as a lateral bud from the secondary protonema, featuring upright, slender axes with spirally arranged leaves.
Mosses are attached to the soil through branched rhizoids.
Vegetative reproduction happens through fragmentation and budding in the secondary protonema.
Sex organs, antheridia and archegonia, are produced at the apex of leafy shoots.
The sporophyte in mosses, which develops after fertilization, is more elaborate than in liverworts.

Pteridophytes

Pteridophytes, including horsetails and ferns, are used for medicinal purposes, soil binding, and as ornamentals.
They are the first terrestrial plants to possess vascular tissues – xylem and phloem.
Pteridophytes thrive in cool, damp, shady places, though some can tolerate sandy soil conditions.
The dominant phase of the life cycle is the sporophyte, which is differentiated into a true root, stem, and leaves.
Pteridophyte leaves can be microphylls (e.g., Selaginella) or macrophylls (e.g., ferns).

Gymnosperms

Gymnosperms are plants with ovules that remain exposed before and after fertilization.
They include medium-sized to tall trees and shrubs.
Sequoia, a gymnosperm, is known as the tallest tree species.
Gymnosperms have tap roots and may form mycorrhizae (e.g., Pinus) or coralloid roots with nitrogen-fixing cyanobacteria (e.g., Cycas).
Their stems can be unbranched (e.g., Cycas) or branched (e.g., Pinus, Cedrus).
Gymnosperm leaves are adapted to withstand temperature extremes, humidity changes, and wind.
Conifers have needle-like leaves, thick cuticles, and sunken stomata to reduce water loss.
Gymnosperms are heterosporous, producing haploid microspores and megaspores.

Algae

Photosynthetic organisms that increase dissolved oxygen levels in their environment.
Primary producers of energy-rich compounds, forming the base of aquatic food chains.
Many species are used as food, including Porphyra, Laminaria, and Sargassum.
Certain brown and red algae produce hydrocolloids, such as algin (brown algae) and carrageen (red algae), used commercially.
Agar is obtained from Gelidium and Gracilaria and is used in growing microbes and food products like ice cream and jelly.
Chlorella, a unicellular alga, is rich in proteins and used as a food supplement, even by space travellers.
Algae are classified into three main classes: Chlorophyceae, Phaeophyceae, and Rhodophyceae.

Chlorophyceae (Green Algae)

Plant bodies can be unicellular, colonial, or filamentous.
Typically grass green due to chlorophyll a and b.
Contain chloroplasts with various shapes, including discoid, plate-like, reticulate, cup-shaped, spiral, or ribbon-shaped.
Chloroplasts often contain pyrenoids which store protein and starch.
Some store food as oil droplets.
Cell walls consist of cellulose and pectose.
Vegetative reproduction occurs through fragmentation or spore formation.
Asexual reproduction via flagellated zoospores.
Sexual reproduction exhibits variation in sex cell type and formation, including isogamous, anisogamous, and oogamous.
Common examples: Chlamydomonas, Volvox, Ulothrix, Spirogyra, and Chara.

Phaeophyceae (Brown Algae)

Primarily found in marine habitats.
Diverse in size and form, ranging from simple filamentous forms (e.g., Ectocarpus) to large kelps reaching 100 meters in height.
Possess chlorophyll a, c, carotenoids, and xanthophylls, resulting in colors from olive green to brown depending on the fucoxanthin content.
Store food as complex carbohydrates like laminarin and mannitol.
Cell walls are composed of cellulose and covered in a gelatinous algin coating.
Plant bodies are attached to substrates through a holdfast, which connects to a stipe (stalk) and a frond (leaf-like photosynthetic organ).
Vegetative reproduction happens through fragmentation.
Asexual reproduction via biflagellate, pear-shaped zoospores with two unequal laterally attached flagella.
Sexual reproduction can be isogamous, anisogamous, or oogamous, with gamete fusion occurring in water or within the oogonium (in oogamous species).
Gametes are pear-shaped with two lateral flagella.
Common examples: Ectocarpus, Dictyota, Laminaria, Sargassum, and Fucus.

Rhodophyceae (Red Algae)

Dominated by the red pigment, r-phycoerythrin, giving them their characteristic color.
Mainly marine and concentrated in warmer areas.
Found in well-lit shallow waters and deeper regions where light penetration is low.
Thalli (plant bodies) are mostly multicellular and some have complex organization.
Store food as floridean starch, similar to amylopectin and glycogen.
Vegetative reproduction through fragmentation.
Asexual reproduction via non-motile spores.
Sexual reproduction is oogamous with complex post-fertilization development.
Sexual reproduction involves non-motile gametes.
Common examples: Polysiphonia, Porphyra, Gracilaria, and Gelidium.

Bryophytes

Include mosses and liverworts, found in moist shaded areas.
Often called amphibians of the plant kingdom due to their terrestrial habitat with dependence on water for reproduction.
Crucial for plant succession in bare areas.
Plant bodies are more complex than algae, being thallus-like and either prostrate or erect.
They attach to substrates via rhizoids.
Lack true roots, stems, or leaves, but may have root-like, leaf-like, or stem-like structures.
The dominant plant body is a haploid gametophyte, which produces gametes.
Sex organs are multicellular: antheridia (male) produce biflagellate antherozoids, and archegonia (female) produce a single egg.
Fertilization occurs in water, with antherozoids fusing with eggs to produce zygotes.
Zygotes develop into sporophytes, which are attached to and dependent on the gametophyte for nutrition.
Spore production occurs within the sporophyte through meiosis, creating haploid spores that germinate into gametophytes.

Gymnosperms

Plants with ovules not enclosed within an ovary wall.
Seeds are exposed after fertilization, hence "naked-seeded plants".
Produce microspores and megaspores, formed in microsporangia and megasporangia, respectively.
Sporophylls (microsporophylls and megasporophylls) are arranged on an axis, forming male and female cones.
Pollen grains germinate and release male gametes through pollen tubes into the ovule, where fertilization with the egg in archegonia occurs.
Zygotes develop into embryos and ovules into seeds.

Angiosperms

Divided into two classes: dicotyledons and monocotyledons.

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This quiz covers essential concepts in taxonomy and the classification of algae. It explores modern taxonomy, including numerical and cytotaxonomy, as well as the reproductive methods of algae. Test your knowledge on these foundational topics in biology!

NCERT - PLANT KINGDOM - 24-25

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Questions and Answers

Which of the following is a method of reproduction in algae?

All algal species are exclusively aquatic organisms.

Name one type of chemical information used in chemotaxonomy.

The term for the fusion of two dissimilar gametes in algae, such as Eudorina, is called __________.

Match the following algal terms with their descriptions:

What is a primary characteristic of algae?

Cytotaxonomy relies on the behavioral characteristics of organisms.

What role do algae play in carbon dioxide fixation?

What is the primary role of marine algae in aquatic ecosystems?

All species of marine algae produce significant amounts of hydrocolloids.

Name two examples of green algae.

The storage bodies located in the chloroplasts of green algae are known as _______.

Match the following classes of algae with their characteristics:

Which of the following is a unicellular alga rich in proteins, often used as a dietary supplement?

The cell walls of green algae consist of only cellulose.

What type of reproduction is common in green algae?

Which of the following characteristics is shared by Chlorophyceae and Phaeophyceae?

All algae reproduce exclusively sexually.

What type of reproduction do Rhodophyceae undergo?

The major stored food in Phaeophyceae includes __________.

Which pigment is primarily found in Rhodophyceae?

What is the habitat of Chlorophyceae?

Match the following classes of algae with their corresponding characteristics:

Polysiphonia and Porphyra are examples of __________ algae.

What are the male and female sex organs called in gametophytes?

All gymnosperms have their ovules enclosed by an ovary wall.

Name one genus of pteridophytes that is heterosporous.

The formation of the zygote occurs when the male gamete fuses with the _______ present in the archegonium.

Match the following classes of pteridophytes with their examples:

Which of the following features make gymnosperms well-adapted to withstand extreme conditions?

Pteridophytes are considered non-vascular plants.

What type of roots are associated with nitrogen-fixing cyanobacteria in some gymnosperms?

What are the two main classes of angiosperms?

Bryophytes require water for sexual reproduction.

What structure in bryophytes bears male sex organs?

The smallest angiosperm is called __________.

Match each type of plant with its characteristics:

What kind of plant structure is produced after the fertilization of the zygote in bryophytes?

The main plant body of bryophytes is called a sporophyte.

What type of spore formation do algae primarily exhibit?

Which of the following classification systems is based on evolutionary relationships?

Algae are still classified under the kingdom Plantae in modern classification systems.

Who proposed the classification system that includes the Five Kingdoms?

The main component of cell walls in green algae is __________.

Match the following types of plants with their characteristics:

Which of the following characteristics is emphasized in natural classification systems?

Artificial classification systems rely heavily on environmental factors.

What is the primary method of classification that separates closely related species by using only a few characteristics?

What is the classification method that assigns numbers and codes to observable characteristics?

Algae can reproduce through vegetative, asexual, and sexual methods.

What is the term for the fusion of two similar-sized gametes in algae?

The primary photosynthetic pigment found in algae is __________.

Which of the following is a well-known form of brown algae?

Match the following algal forms with their descriptions:

All algae are autotrophic and depend on other organisms for food.

What is the process called where algae carry out carbon dioxide fixation?

What is the primary role of marine algae in aquatic ecosystems?

Chlorophyceae are commonly referred to as brown algae.

Name one commercial product obtained from red algae.

The rigid cell wall of green algae consists of an inner layer of __________ and an outer layer of __________.

Match the following types of algae with their characteristics:

Which type of algae is known for having large amounts of proteins and is used by space travelers?

Phaeophyceae are primarily found in freshwater habitats.

What pigment is responsible for the brown color in Phaeophyceae?

Which pigment is NOT found in Phaeophyceae?

All classes of algae reproduce sexually.

Name a common habitat for Bryophytes.

The primary stored food in Rhodophyceae is __________.

Match the types of algae with their respective pigments:

What type of reproduction is characteristic of Rhodophyceae?

Chlorophyceae are primarily found in marine environments.

List one of the common members of Rhodophyceae.

What is the primary role of bryophytes in the ecosystem?

Bryophytes have true roots, stems, and leaves.

What is the male sex organ called in bryophytes?

The structure where the female gamete is produced in bryophytes is called the ______.

The rigid cell wall of green algae consists of an inner layer of and an outer layer of .

Green algae are primarily characterized by the presence of chlorophyll and .