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Kingdom Protista Morphological Diversity - some species form statospores Holdfast - possess membrane-bound organelles and a nucleus - broadly classified into two groups-based symmetry:...

Kingdom Protista Morphological Diversity - some species form statospores Holdfast - possess membrane-bound organelles and a nucleus - broadly classified into two groups-based symmetry: - the statospores helps the cell survive harsh or - an anchor that attaches algae to a surface like rocks, - can be unicellular, colonial, or multicellular centric diatoms, which possess radial symmetry, and unfavorable conditions coral, or the sea floor - autotrophic, heterotrophic, or mixotrophic pennate diatoms, characterized by bilateral - common in brown algae (kelps), red algae, and - primarily found in moist or aquatic environments symmetry. Phylum Rhodophyta – Red Algae some green algae - asexual and sexual - mostly seaweeds found in warmer, deeper waters, some as deep as 269 meters where light is minimal Stipe Cellular Organization - they can be unicellular or filamentous - a stem-like structure that connects the holdfast to Basic Differences Among Protists - diatoms are eukaryotic cells, possessing a nucleus, - often forming delicate, feathery structures. the blades. It supports the algae and positions blades Mode of Locomotion chloroplasts for photosynthesis, mitochondria, and - three types of thallus: male gametophyte, female in a way that maximizes exposure to light - Flagella, Cilia or Pseudopodia other typical organelles. gametophyte, tetrasporophyte - mostly in brown algae but also in some green algae - they reproduce with non-moving gametes that are Types of Nutrition Comparative Analysis: Diatoms and other carried by water currents Blade - Producers, Consumers and Decomposers Chromists - after fertilization, the zygote grows into a structure - are leaf-like parts of the algae, where Diatoms (Bacillariophyceae): called a cystocarp, which produces spores photosynthesis takes place. They are thin and broad Structural Diversity - unicellular algae characterize by intricate silica cell - their red to purplish color comes from pigments to maximize surface area for sunlight absorption - Ranges from single-celled organisms to large walls, known as frustule. They are predominantly called phycobilins, along with chlorophyll - found in brown algae, red algae, and green algae multicellular seaweeds non-motile, although their gametes exhibit flagella. Brown Algae (Phaeophyceae) Phylum Dinophyta – Dinoflagellates Bladder Significance of Kingdom Protista - multicellular algae with cellulose cell walls, - a red tide happens when dinoflagellates increases in - help algae float, keeping them closer to the water number very quickly surface where they can get more light for 1. Ecological Role – Producers in aquatic food chains primarily inhabiting marine environments where they - have special characteristics such as armor-like photosynthesis (e.g. Phytoplankton), Decomposers recycling form extensive kelp forests; non-motile; primary shells, two flagella, and chloroplasts - mainly in brown algae (kelps), though some red nutrients (e.g. Slime Molds) producers - some types of dinoflagellates release toxins that algae may have similar mechanisms to float. 2. Economic Importance – Algae as a source of food, Dinoflagellates (Dinophyceae) build up in shellfish biofuel, and industrial products. - unicellular organisms with cellulose plates (theca) Phylum Euglenophyta – Euglenoids Thallus 3. Medical Relevance – Some protists cause diseases and two flagella, enabling motility. Many are - algae found in places like ponds and sewage - plant body of the algae (e.g. Malaria by plasmodium), Research models for photosynthetic, some are mixotrophic. Found in treatment areas - vary greatly in form, from simple, undifferentiated understanding cell biology. freshwater and marine environments. - shaped like a spindle and it doesn’t have a rigid, structures to complex, multipart bodies hard outer structure like some other cells Structural parts of the algae Diatoms: Structure, Form, and Phylum Evolutionary Origins: Secondary Symbiosis - has a pellicle that helps it maintain shape while still Chromophyta Comparisons - the chloroplasts in diatoms originated through being able to change form Diatoms are unicellular algae characterized by their secondary symbiosis, involving the engulfment of a - has two flagella: long flagellum- move through Slime Molds water; short flagellum- detect light Cell wall composition unique silica-based cell walls, called frustules. red alga. - some species are photosynthetic; some species - slime molds and water molds lacks chitin in their Diatoms are unicellular algae, also known as Phylum Chlorophyta – Green Algae consume food by ingestion walls phytoplankton, inhabiting a wide range of aquatic - found in freshwater, oceans, and unique habitats - instead, slime molds either lack cell walls or have environments. They play a crucial role in aquatic like tree bark, sloth fur, and snowbanks. They are key Structural parts of the algae cell walls made of cellulose in certain stages food webs and global carbon cycling. Their defining plankton contributors. - water molds have cell walls primarily composed of characteristics is the intricate silica cell wall, known - sharing pigments (chlorophyll a and chlorophyll b) cellulose, a characteristic more common in plants as a frustule. and storing starch in chloroplasts. - exhibit a wide variety of shapes and structures: Nutrition microscopic unicellular species, filaments, colonies, Frustule Structure and Function - slime molds are heterotrophic and feed via seaweed-like structures. - consists of two overlapping halves: the epitheca and phagocytosis - most are unicellular hypotheca, provides both structural support and - water molds are saprotrophic or parasitic and lack - reproduce both sexually and asexually protection for the diatom cell the enzymatic pathways typical of fungi - the intricate patterns and pores on the frustule Phylum Chromophyta Life Cycle and Reproduction surface are species-specific, making them valuable - about 7,600 species, mostly microscopic - slime molds alternate between amoeboid, motile tools for identification - kelp and other brown seaweed stages and a stationary spore-producing stage, - common characteristics: food reserves, specialized resembling protists more than fungi pigments, unique cell structure - water molds produce zoospores with flagella Motility Most fungi consist of a network of filaments called Phylum Glomeromycota Reproduction: - slime molds exhibit motility during their life cycle, hyphae, which form a mycelium. These hyphae may Habitat: Mostly terrestrial, forming symbiotic Asexual reproduction is rare; involves conidia with an amoeboid stage that can move to seek food be septate (with cross-walls) or coenocytic (without relationships with plants. or fragmentation - water molds also produce motile, flagellated spores. cross-walls). Structure: Sexual reproduction involves basidiospores 6. Reproduction: Hyphae are coenocytic. produced on the surface of the basidium, Phylum Myxomycota – Plasmodial Slime Molds Fungi reproduce via both sexual and asexual spores, Form arbuscules (branched hyphal structures) usually on fruiting bodies. - consists of unique, fungus-like organisms which can be dispersed by wind, water, or animals. within plant root cells. - multinucleate, amoeba-like mass called the 7. Lack of Chlorophyll: Unique Features: Phylum Microsporidia plasmodium, which moves and grows through its Unlike plants, fungi do not have chlorophyll and Obligate symbionts, forming arbuscular Habitat: Obligate intracellular parasites, mainly environment, engulfing bacteria, spores, and organic cannot photosynthesize. This is why they depend mycorrhizae with the roots of most land plants, infecting animals, including insects and humans. material entirely on organic matter for their energy aiding in water and nutrient absorption. Structure: 8. Storage Molecule: Unicellular and lack typical fungal features like Reproduction Phylum Dictyosteliomycota – Cellular Slime Fungi store energy in the form of glycogen, similar mitochondria. Asexual: Reproduces exclusively through Molds to animals. This shared characteristic highlights their large, multinucleate spores. Produce highly resistant spores capable of - consists of slime molds that exhibit a unique life unique position in the tree of life. Sexual: No known sexual reproduction; relies surviving harsh conditions. cycle on forming arbuscular mycorrhizae in plant Unique Features: - exists as individual amoeba-like cells during most Phylum Chytridiomycota (Chytrids) roots for survival and spread Lack conventional hyphae. of their life Habitat: Primarily aquatic, but some are found in Use a polar tube to inject their genetic material moist terrestrial environments. Phylum Ascomycota (Sac Fungi) into host cells. Phylum Oomycot – Water Molds Structure: Mostly unicellular; some species form - includes a group of fungus-like organisms that Habitat: Found in diverse habitats, including soil, Reproduction: simple, coenocytic hyphae. thrive in aquatic environments, as well as in moist decaying matter, plants, and as symbionts (lichens). Spore formation is their primary means of Unique Features: terrestrial habitats. Structure: Hyphae are septate (divided by cross- reproduction. Produce zoospores, the only motile spores walls with pores). among fungi, which have flagella for Unique Features: Form and Functions swimming. Named after their ascus, a sac-like structure KINGDOM FUNGI Considered the most primitive fungi, showing where sexual spores (ascospores) are produced. 1. Sporangium (Asexual reproduction of Phylum General Features evolutionary links to protists. Includes yeasts (unicellular), molds, and more Zygomycota) 1. Eukaryotic Organisms: Nutrition: Saprophytic or parasitic (notably on - a specialized structure found in various organisms complex fungi like Morchella (morels) and Fungi are eukaryotic, meaning their cells have a true amphibians, causing chytridiomycosis). including plants, and fungi, where spores are Tuber (truffles). nucleus enclosed in a membrane and other Reproduction: produced and stored. Spores are reproductive units Many species reproduce asexually by organelles. Asexual reproduction through zoospores. producing conidia (spores on specialized that serve as a means for reproduction, survival, and 2. Heterotrophic Nutrition: Sexual reproduction forms resting sporangia. hyphae). dispersal. Fungi are heterotrophs, which means they rely on FORM: Reproduction: organic matter for nourishment. They can act as Phylum Zygomycota (Zygomycetes) - It is often a spherical or sac-like structure which saprophytes, breaking down dead materials, parasites Asexual is common; forms conidia or through Habitat: Terrestrial; found in soil, decaying organic develops on top of a certain hyphae called feeding on living hosts, or mutualists, forming budding (in yeasts). matter, or as parasites. sporangiophore in fungi like Rhizopus (bread mold). beneficial relationships with other organisms Sexual reproduction involves formation of Structure: Hyphae are coenocytic (multinucleate FUNCTION: 3. Cell Wall Composition: ascospores in asci, often contained within and non-septate). Spore Production: Unlike plants, whose cell walls are made of cellulose, fruiting bodies called ascocarps. Unique Features: - Meiotic spores: are haploid and lead to sexual fungal cell walls are primarily composed of chitin, a Formation of a zygosporangium during sexual reproduction strong and flexible material also found in the Phylum Basidiomycota (Club Fungi) reproduction, which is a thick-walled structure - Mitotic spores: are genetically identical to the exoskeletons of insects. This unique composition Reproduction: that protects the zygospore during adverse parent and are involved in asexual reproduction gives fungi their structural strength. Habitat: Mostly terrestrial; found in forests, soil, conditions. Spore Protection: 4. Absorptive Nutrition: and decaying organic material. Common examples include Rhizopus (black - it provides safe environment for the spores as they Fungi secrete digestive enzymes into their Structure: develop ensuring they are viable for dispersal bread mold) and Mucor. surroundings, breaking down organic material Hyphae are septate. Spore Dispersal: Reproduction: externally. They then absorb the digested nutrients, Often form complex fruiting bodies called - Once mature, the sporangium release spores into the Asexual reproduction via sporangiospores in basidiocarps (e.g., mushrooms). which is why we often find them thriving on environment to spread and establish new individuals. sporangia. decaying matter Unique Features: Named after the basidium, a club- This dispersal may rely on mechanisms like wind, Sexual reproduction involves fusion of 5. Body Structure: shaped structure where sexual spores water, or mechanical forces for germination specialized hyphae to form zygospores. (basidiospores) are formed. 2. Coenocytic open to release numerous spores. Black bread molds 1, 2, 3, and 4. Only types 1 and 3, or types 2 and 4, ascospores, which are arranged in a row within the - refers to multinucleate hyphae that lack septa reproduce sexually by conjugation. Although there is can mate with each other. ascus. (cross-walls) resulting in a continuous cytoplasmic no visible difference in form, black bread mold - If the growth of the hyphae of compatible mating mass mycelia occur in two different mating strains, often types happens to bring them close together, cells of 8. Basidium - found in fungi like zygomycetes (e.g., Rhizopus) indicated as “+” and “-”. each mycelium may unite, initiating a new mycelium - A club-shaped structure found in basidiomycetes FUNCTION: - When a hypha of one strain encounters a hypha of in which each cell has two nuclei. that produces basidiospores - allows efficient transport of nutrients and organelles the other, the chemicals they produce create an - Such a mycelium is said to be dikaryotic. Dikaryotic Role of the Basidium in Sexual Reproduction: throughout the hyphal network attraction, and swellings called progametangia mycelia sometimes have little, walled-off bypass - Inside the basidiocarp, specialized club-shaped cells *The hyphae of most fungi are divided into cells by develop opposite each other on the hyphae. loops called clamp connections between cells on the called basidia develop on structures such as gills, internal walls called septa (singular, septum). Septa - The progametangia grow toward each other until surface of the hyphae. pores, or the surface of the fruiting body. usually have little pores that are large enough to they touch. A crosswall is formed a short distance - The clamp connections develop as a result of a - Within each basidium, the following processes allow ribosomes, mitochondria and sometimes nuclei behind each tip, and the two gametangia merge, unique type of mitosis that ensures each cell will have occur: to flow among cells. Hyphae that are divided into becoming a single, large, multinucleate coenozygote one nucleus of each original mating type within it. Karyogamy: cells are called septate hyphae. However, the hyphae in which the nuclei of the two strains fuse in pairs. A - After developing for a while, the dikaryotic The two nuclei (n + n) in each basidium fuse to form of some fungi are not separated by septa. Hyphae thick, ornamented wall then develops around this mycelium may become very dense and form a a single diploid (2n) nucleus. without septae are called coenocytic hyphae. coenozygote or zygospore with its numerous diploid compact, solid-looking mass called a button. Meiosis: Coenocytic hyphae are big, multinucleated cells. nuclei. - This pushes above the surface and expands into a The diploid nucleus undergoes meiosis, producing - This structure, called a zygosporangium, is the basidioma (formerly known as a basidiocarp), four haploid nuclei. 3. Mycelium characteristic sexual spore of members of this commonly called a mushroom. Basidiospore Formation: - A network of hyphae that forms the vegetative body division These haploid nuclei migrate into four external of a fungus 7. Ascus (sexual reproduction of ascomycetes) projections (sterigmata) on the basidium, where they - can be extensive, covering large areas, and exists 5. Conidium (asexual reproduction Phylum - a sac-shaped cell present in ascomycete fungi; it is develop into haploid basidiospores. either as single or branching filaments. Ascomycota) a reproductive cell in which meiosis and an additional FUNCTION: FORM: cell division produce eight spores - Absorption: primary function is to absorb nutrients - A non-motile asexual spore produced externally, - develops within the fruiting body (ascocarp) Spore Dispersal: Mature basidiospores are released from the environment. either singly or in chains at the tips of hyphae called from the basidia, often propelled by a mechanism - Colonization: Mycelium grows and expands to conidiophores *Sexual reproduction in sac fungi involves the called the Buller’s drop (a surface tension-based explore and exploit new food sources - spherical, elongated, or branched formation of tiny sacs called asci (singular: ascus). In mechanism). - Reproductive support: provides the base for FUNCTION: some species, male structures (antheridia) form on structures like sporangia or conidiophores - Asexual reproduction: helps fungi reproduce one fungal body and female structures (ascogonia) on Wind, water, or animals help disperse the spores to *Most fungi grow as thread-like filaments, like those quickly without sexual processes another. However, both structures can develop on the new environments. shown in Figure below. The filaments are called - Dispersal: adapted for spreading by wind, water, or same mycelium in many species. Hyphae connect This dispersal is vital for colonizing new substrates hyphae (singular, hypha). Each hypha consists of one animals antheridia and ascogonia, allowing male nuclei to and ensuring the spread of the fungus. or more cells surrounded by a tubular cell wall. A - Survival: dormant conidia can endure harsh move into the ascogonium. mass of hyphae makes up the body of a fungus, which conditions until they become favorable *Inside the ascogonium, male and female nuclei pair Germination and Restart of the Cycle: When is called a mycelium (plural, mycelia). up but do not fuse. Specialized hyphae (ascogenous basidiospores land in a suitable environment, they 6. Dikaryotic hyphae) grow from the ascogonium, with each cell germinate to produce new haploid mycelia, 4. Zygospore (sexual reproduction of Phlyum - a cell or hypha containing two genetically distinct containing one male and one female nucleus. These completing the cycle. Zygomycota) nuclei, one from each parent, which does not cells divide uniquely, maintaining one nucleus of - a thick-walled, resistant spore formed during the immediately fuse. each type. At the tip of an ascogenous hypha, a hook- Examples of True Fungi sexual reproduction of zygomycetes - found in fungi like basidiomycetes and ascomycetes like structure called a crozier forms. The nuclei in the 1. Athlete’s Foot - formed by the fusion of specialized hyphae called during the sexual reproduction phase. crozier divide, and crosswalls create three cells: the - Or, medically known as Tinea pedis, is caused by gametangia Reproduction: middle cell holds one male and one female nucleus Trichophyton spp. These fungi belong to the FUNCTION: - When a spore lands in a suitable place—often an and develops into an ascus. dermatophyte group. They are responsible for - Sexual reproduction: carries genetic material from area with good organic material and humus in the causing various skin, hair, and nail infections in two parent fungi. soil—it germinates and produces a mycelium just *In the ascus, the two haploid nuclei fuse to form a humans and animals. - Survival:enables the fungus to withstand beneath the surface. diploid zygote nucleus. The asci form in a layer unfavorable environmental conditions - The hyphae of the mycelium are divided into cells (hymenium) on the surface of a structure called an 2. Dutch Elm Disease - Germination: Upon favorable conditions, the that each contain a single haploid nucleus. Such a ascoma (formerly ascocarp). The zygote nucleus caused by a member of the sac fungi (Ascomycota), zygospore germinates to produce new mycelium mycelium is said to be monokaryotic. undergoes meiosis, producing four haploid nuclei, Ophiostoma spp. This disease, caused by species like *Rhizopus reproduces asexually by producing - Monokaryotic mycelia of club fungi often occur in which then divide by mitosis to produce eight nuclei. Ophiostoma ulmi and Ophiostoma novo-ulmi, has sporangia at the end of sporangiophores. Sporangia four mating types, usually designated simply as types These nuclei are enclosed in cytoplasm to form devastated elm populations worldwide. It is spread by bark beetles, these fungi infect trees and disrupt 8. Chestnut Blight Fungus Phylum Basidiomycota - Crustose lichens are attached to or embedded in their water transport system, leading to wilting, - Cryphonectria parasitica is a pathogenic fungus 1. Agaricus bisporus (Button Mushrooms): This their substrate over their entire lower surface. - They yellowing leaves, and eventual death. classified in Phylum Ascomycota. It was accidentally versatile fungus is widely cultivated and consumed often form brightly colored, crusty patches on bare introduced to North America from Asia, causing worldwide, adding flavor and nutritional value to rocks and tree bark. The hyphae of some that grow 3. Pilobolus decimation of the once numerous American chestnut countless dishes. on sedimentary rocks penetrate as much as 1 - Belongs in the Phylum Zygomycota group, this trees from the eastern deciduous forest. 2. Lentinula edodes (Shiitake Mushrooms): centimeter (0.4 inch) into the rock. Others grow just species is known for its unique reproductive strategy. 9. Puffball Renowned for their umami flavor and medicinal beneath the cuticle of the leaves of tropical hardwood Often found growing on dung, mature sporangia of - Puffballs belong to the division Basidiomycota and properties, shiitake mushrooms are cultivated and trees, with no apparent harm to the leaves. Pilobolus are catapulted, where they adhere to grass encompass several genera, including Calvatia, consumed in many parts of the world. or other vegetation. When the vegetation is ingested Calbovista and Lycoperdon. They are stalkless club 3. Pleurotus ostreatus (Oyster Mushrooms): These by animals, the spores germinate in the digestive tract fungi that may each produce trillions of spores. easily cultivated mushrooms are a popular choice for - Foliose lichens have somewhat leaflike thalli, and are already growing in the dung when it is 10. Smut home cultivation and commercial production, which often overlap one another. They are weakly released. - They are a group of fungi belonging to the Phylum providing a sustainable and nutritious food source. attached to the substrate. The edges are frequently Basidiomycota, characterized by their large numbers 4. Ganoderma lucidum (Reishi Mushrooms): Used in crinkly or divided into lobes. 4. Penicillium mold of teliospores. These fungi can infect a wide range of traditional Chinese medicine for centuries, reishi - Fruticose lichens may resemble miniature upright - Penicillium is a genus of fungi commonly known as plant species, including cereals, grasses, and mushrooms are prized for their potential health shrubs, or they may hang down in festoons from blue or green mold. Some species are used in food ornamental plants. benefits, including immune-boosting properties. branches. Their thalli, which are usually branched, production, such as cheesemaking, while others can 5. Ustilago maydis (Corn Smut): While often are basically cylindrical in form and are attached at cause food spoilage. Notably, some species of Economically Important Fungi considered a crop pathogen, it does not usually cause one point. Penicillium are sources of penicillin, the well-known significant economic losses. Corn smut can be a - It should be stressed that while lichens may be and widely used antibiotic in the world. Phylum Chytridiomycota culinary delicacy in certain cultures, particularly in attached to trees or other plants, the majority in no 1. Batrachochytrium dendrobatidis, causes a disease Mexico, where it is known as huitlacoche. way parasitize them. There are, however, a very small 5. Stinkhorn in amphibians called chytridiomycosis. This disease number of species that do produce parasitic rhizines - Stinkhorns are a unique group of fungi belonging to is believed to be a major cause of amphibian Lichens that penetrate the cortical parenchyma cells of their the phylum Basidiomycota. They are known for their population declines worldwide. consists of a fungus and an alga (cyanobacterium) hosts. foul odor, whose odor attracts flies; the flies associated with a spongy thallus. disseminate the sticky spores that adhere to their Phylum Zygomycota a prime example of a symbiotic relationship bodies and its phallic shape when mature. 1. Rhizopus - Black bread mold, used in food - mutualism BRYOPHYTES - Phallus impudicus and Mutinus caninus production, especially tempeh. - parasitism 2. Mucor spp. - It's used to produce ethanol, and has - Gr. ‘bryon’ (tree moss, liverwort), and ‘phyon’ 6. Yeast a large array of sugars it can use as a food source. It How are lichens identified? (plants). - Yeasts are single-celled microorganisms that are is also used as fish feed and may be a valuable tool to - There are about 14,500 known species of lichens. - primitive members of Plant Kingdom classified in the phylum Ascomycota group. They are clean up oil spills. - The photosynthetic component is either a green alga - referred as “amphibians of the plant world” characterized by their ability to ferment sugars, 3. Actinomucor elegans and Mucor spp. - used with or a cyanobacterium, with a few lichens having two - grows in shady and damp areas producing alcohol and carbon dioxide as byproducts. soybeans to make a Chinese cheese called sufu. species of algae present. The photosynthetic partner - non-vascular and non-flowering plants These are usually used in industrial applications such 4. Phycomyces blakesleeanus - potential producers of in lichens may be any of about 100 species of algae - absorbs water through surface tissues and as baking, brewing, and food production. food-coloring pigments, used in food production. or blue-green bacteria. cuticle - Saccharomyces cerevisiae 5. Blakeslea trispora - used as manufacturing yellow - Each lichen also has its own unique species of food coloring agents (margarine). fungus. It is possible to isolate and culture the components separately. When this is done, however, Distinguishing Features 7. Ergot Phylum Ascomycota the fungus takes on a very different, compact but - absence of true roots, stem and leaves - Ergot is a fungal disease that affects cereal grains, 1. Morels (Morchella esculenta) and Truffles (Tuber indefinite shape, and the algae or cyanobacteria grow - small and low-growing primarily rye. It's caused by fungi Claviceps spp.) - They are known for their unique flavors and faster than they do when they are part of a lichen. - thrives in moist and shaded environments purpurea. This fungus seldom causes serious damage textures, making them sought-after delicacies. - The fungal component is very rarely found growing - requires water for fertilization to the crop, but as it develops in the maturing grain, 2. Ergot - This fungus seldom causes serious damage independently in nature, while the photosynthetic - reproduce through spores it produces several powerful drugs. If the infected to the crop, however it can also produce several component is known to thrive independently of the - dominant gametophyte (haploid) phase grain is harvested and milled, a disease called powerful drugs. lichen in some instances. Lichen species, therefore, - survives extreme desiccation ergotism may occur in those who eat the 3. Yeast - used for baking and brewing process. are identified according to the fungus present. - lacks true xylem and phloem and instead have contaminated bread. The disease can affect the 4. Dutch Elm - negative impact to economy, resulting central nervous system, often causing hysteria, in loss of property value. How are lichens classified? specialized cells: hydroids for water convulsions, and sometimes death. 5. Chestnut Blight - economic loss in timber and food - Lichens have been loosely grouped into three major conduction and leptoids for nutrient and sugar industries. growth forms. transport Phylum Hepaticophyta (Liverworts) Gametophyte Generation (n) Mosses: - “wort” means plant or herb - Protonema is the first stage of the gametophyte’s - Structure: more complex sporophyte with a stalk - 8000 species development (seta), capsule, and often a lid (operculum) for spore - gametophytes grow horizontally, have a flattened or - mature gametophyte is the dominant phase of the release. Contains stomata for gas exchange leafy (thalli), that may resemble lobes of animal liver moss life cycle, the green, leafy structure we typically - Development: Spores are released from the capsule appearance see. Differentiated into: leaves, rhizoids, antheridia, when the operculum opens, often with help from a - sporophytes do not contain stomata archegonia peristome. - uses elasters, a type of cells that can change their - male gametophyte: produce sperm in antheridia shape depending on the moisture content of the - female gametophyte: produce eggs in archegonia Importance of Bryophytes dispersal of spores - Healing abilities - cuplike structures that produce spores asexually, Sporophyte Generation (2n) - Used as packaging material although sexual reproduction also takes place to - the sporophyte is completely dependent on the - Habitat for wildlife produce the sporophyte gametophyte for its nutrition and water - Soil conditioner - foot: this is the base of the sporophyte, embedded in - Erosion control Phylum Anthocerophyta (Hornworts) the gametophyte tissue - Water retention - thrive in moist and shaded areas - seta (stalk): this is a slender stalk that elevates the - Indicator species - 100 species sporangium, improving spore dispersal - Nutrient Cycling - has stomata - sporangium (capsule): this is the structure where - Pioneer species - asexual and sexual reproduction meiosis occurs - Biomonitoring - utilize pseudo-elaters to aid in spore dispersal - gametophytes may resemble those of liverworts, Meiosis and Fertilization sometimes with a crumpled appearance and, after - Meiosis: occurs within the sporangium. The fertilization, the sporophyte resembles a hornlike sporocytes undergo meiosis, producing haploid structure spores. The number of spores produced varies greatly depending on the species Phylum Bryophyta - Fertilization: occurs within the archegonium. The - 15000 species sperm, released from the antheridia, swim through a - 3 classes: peat, true, rock film of water to reach the egg in the archegonium. - no mesophyll, stomata, veins The fusion of the sperm and egg nuclei results in a - gametophytes vary but can have stemlike and diploid zygote. leaflike structures that make them distinguishable from liverworts and hornworts. Sporophytes What are Sporophytes? produces after fertilization often tower above the - Sporophytes ae the diploid phase in a plant’s life gametophyte generation and release spores from cycle that produce spores. They grow from a unique sporangia fertilized egg (zygote) and are typically dependent on the gametophyte in nonvascular plants like mosses and liverworts. How do their sporophytes differ? Liverworts: - Structure: simple sporophyte with a short stalk (seta) and a capsule. Lacks stomata and depends on the gametophytes for nutrients - Development: Capsule splits into valves to spores Stoneworts: - Structure: No true sporophyte; instead, they form Life cycle of a Moss zygospores, which are thick-walled and act as a - the moss life cycle alternates between a haploid dormant phase. gametophyte generation and a diploid sporophyte - Development: Zygospore germinates to produce the generation next generation without a multicellular sporophyte