BIO151 SUMMARYIFEANYI PRINCE (1).pdf

CHAPTER 1 : Biology—Definition, Living and Non–Living Things. KEYNOTES: 1. The word is derived from two Greek works "Bios" meaning life and "Logos" meaning study. Therefore, biology is the study of living things. 2. Movement, Respiration, Nutrition, Irritability, Growth, Excretion,...

CHAPTER 1 : Biology—Definition, Living and Non–Living Things. KEYNOTES: 1. The word is derived from two Greek works "Bios" meaning life and "Logos" meaning study. Therefore, biology is the study of living things. 2. Movement, Respiration, Nutrition, Irritability, Growth, Excretion, Adaption, Organization, Reproduction and Death are the characteristics of living things. 3. Excretion is the removal of metabolic waste products from the body. 4. Adaptation is the ability of living things to make changes in their morphology and behavior to suit the conditions of their environment. 5. Irritability is the ability of living things to respond to external stimulus. 6. Respiration is the biochemical process in which the cells of an organism obtain energy by combining oxygen and glucose, resulting in the release of carbon dioxide, water, and ATP. 7. Nutrition is the ability of living things to feed. 8. Reproduction is the production of offspring. 9. Scientific observations are objective rather than subjective, and even the conclusions made after the observations are objective. 10. A systematic and scientific approach of collecting and analysing information is known as Scientific Method. 11. A scientific guess tentatively put forward to explain a natural phenomenon is known as a Hypothesis. 12. A hypothesis that has been verified by different scientists and has worked reliably to a considerable extent is known as a Theory. 13. A theory that has been tested by almost all scientists in the field and accepted universally for a reasonable long time is known as a Law. 14. The steps of a scientific method are as follows:  Accumulation of scientific data.  Formulation of hypothesis.  Observation and experimentation.  New Data.  Theory.  Experimentation by different scientists.  Universal confirmation and acceptance.  Law. CHAPTER 2: The Cell Concept KEYNOTES: 1. A cell is the basic , structural and functional unit of life bounded by a membrane containing nucleus and cytoplasm. 2. Organisms are either cellular or acellular. 3. Cellular organism are ogranisms that contain cells. Cellular microbes include; bacteria, the archaea, the fungi, and the protists ( algae, protozoa, slime molds, and water molds). While acellular organisms are organisms without a cell. Acellular microbes include ; Viruses, viroids and prions. 4. Acellular organisms are organisms without a cell. Acellular microbes include; Viruses, viroids and prions. 5. Viruses lack the capacity for independent metabolism and they're called obligate intracellular organisms. 6. Cells of cellular organisms exists in single independent form, filamentous form, colonial form, and as part of living multicellular organisms. 7. Acellular organisms are non living when they exist on the outside of their host , while they're parasites when inside a host. 8. Each filament cells is independent of adjacent cells in the metabolism of Spirogyra and Oedogonium. 9. Colonial form cells occur as aggregate of cells joined together by strands of cytoplasm. In some Colonial cell forms like Eudorina, each cell is metabolically and reproductively independent of other cells. 10. The cells of multicellular organisms are differentiated and specialized and this makes dependent on one another's activities to live. 11. Based on the presence Or absence of organized nucleus, cells can be classified into prokaryotic and eukaryotic cells. 12. " Pro " means Before and " Karyon " means nucleus. Hence Prokaryotes simply means before nucleus. 13. Prokaryotic cells lack membrane. Bacteria is an example of a prokaryotic cell. 14. " Eu " means true and " Karyon" means nucleus. Hence, Eukaryotes simply means true nucleus. 15. Eukaryotic cells contain a system of membrane. 16. Eukaryotic cells have complex DNA, nucleus, are typically much larger and they exhibit aerobic respiration. While Prokaryotic cells have simpler DNA, Nucleoid, are typically much ser and they exhibit both aerobic and anaerobic forms of respiration. 17. Bacterias reproduce by binary fission. And they can be used for the following: 18. the product of antibiotics, 19. Bioinsecticides of Bascillus sphaericus and Bacillus Thuringiensis. 20. They can also be used for the manufacturing of butter, cheese , youghurt, etc. 21. Bacterias are classified into Order, Families, Genera and Species. 22. Species that look alike are placed in a genus ; related genura form a family and related families are placed in an order. 23. Each bacterium is given two latin names. The first is the generic name and starts with a capital, while the second is the specific name, starting with a small letter. The two names are usually italicized or underlined if handwritten. 24. The names of families and orders of bacteria are not usually italicized but the family name ends in "aceae and the name of an order always end in "ales" 25. Bacterias differ among one another in their morphological characteristics, chemical activities, nutrition and energy requirements, growth requirements and in their reaction to certain dyes. 26. Rods, spherical or coccus, spiral, curved rods or vibrios, and coccobacilli are the general morphological shapes of bacteria. 27. The spherical cells of a bacteria can be arranged as:  Single cells (coccus)  Pairs(diplococcus)  Four in a square arrangement(tetrads)  Chains(streptococcus)  Eight cocci grouped in a cuboidal arrangement(sarcinae)  Clusters or brunches(Staphylococcus).  Rod–shaped bacterial cells are arranged as:  single cells(bacillus/bacilli)  pairs(diplobacilli/diplobacillus)  Chains (streptobacillus/streptobacillus).  The archael domain is a diverse group of extremophilic prokaryotic Microorganisms composed of : 28. The extreme halophiles 29. The methanogens 30. The extreme thermophiles.  31. The extreme halophiles inhabit extremely salty environments. E.g Halo bacterium and halococcus. 32. The methanogens reduce carbondioxide to methane. 33. The extreme thermophiles grow at very high temperature. 34. The Kingdom Euryarcheota is made up of extreme halophiles and methanogens. While the kingdom crenercheota is made up of extreme thermophiles. 35. The archael stain is either Gram +ve or Gram –Ve and may be spherical, rod-shaped spiral or plate–shaped. 36. Archeae lack nucleus, have one ribosome size whush is 70s type, make use of methionine tRNA as initiator, and they're mostly extrememophiles. CHAPTER 3 : Microbial Classification. KEYNOTES : 1. The science of classification of organisms is called Taxonomy. 2. A taxon is group or category of related organisms arranged in a hierarchical order with species at the bottom and domain at the top. 3. Taxa is the plural form of taxon. 4. The taxonomic Hierarchical category is :  Domain  Kingdom  Division  Class  Order  Family  Genus  Species. 5. The three domain of classification developed by Carl woese in 1978 placed all living organisms into Domain Eukarya also known as Eukaryotes , Domain Bacteria also known as Eubacteria, and Domain Archeae also known as Archaebacteria. 6. Normenclature is used in naming of bacteria. 7. Normenclature uses the names of the two lower level taxa , genus and species to name species. Both names are italicized or underlined. The genus name must come first and it's first letter should be capitalized. The genus name may be abbreviated but must be used first before abbreviation. 8. A bacterial species is a collection of strains that share many features in common and differ considerably from other strains. 9. A strain is a category found below the level of species. A strain is not a taxonomic category. 10. A viral species is a population of viruses with similar characteristics occupying a particular ecological niche. CHAPTER 4 : Eukaryotic Protists: Fungi and Algae. KEYNOTES: 1. The prefix "Eu" in eukaryotes simply means true , while karyotes refer to the genetic material. Hence Eukaryotes means true nucleus. 2. Eukaryotes are organisms with complex cells, in which their genetic materials are organized into membrane-bound nucleus.  3. Prokaryotes are organisms such as bacteria and archaea that lack nucleus and other complex cell structures. 4. The following are few differences between d prokaryotic cells: 5. Eukaryotic cells are generally much bigger than prokaryotic cells, and have a variety of membrane enclosed internal structurea called organelles. 6. Eukaryotic cells are also composed of cytoskeleton made up of microtubules, microfilaments and intermediate filaments which play an important role in determining the cells organization and shape. 7. Eukaryotic DNA Is divided into several linear bundles called chromosomes , which are separated by a microtubular spindle during nuclear division. 8. The DNA Of eukaryotes is associated with histone proteins. 9. The nuclear envelope is part of the endomembrane system that extends to include the endoplasmic reticulum, ER to which ribosomes are attached, dictyosomes, and the cell or plasma membrane the encloses the cell. 10. Proteins are manufactured within the machinery of endoplasmic reticulum, golgi apparatus, and ribosomes. 11. Cristae are folding and invaginations inside a mitochondria. Respiration takes place in rhe cristae. 12. Lysosomes contain enzymes that breakdown the content of food vacuoles, and peroxisomes that contain the enzyme catalase required to break hydrogen peroxide down to water and oxygen which otherwise would be toxic to the cell. 13. Plants and various groups of algae contain plastids which usually occur as chloroplast. While chloroplast contains the chlorophyll through which energy is produced during photosynthesis. 14. Eukaryotes contains microfilaments and microtubules. Both are used to provide structural reinforcements and support to the large cells. 15. Microfilaments are made of the protein actin, while microtubules are composed of the protein tubulin, and together these two make up the cytoskeleton. 16. Some eukaryotes like plants and fungi have complex cell walls made of cellulose and chintin. 17. Viz, plants , animals, and protists were the traditional four kingdoms of Eukarya Or Eukaryotes before the era of molecular phylogeny. 18. Fungi and microbial Eukaryotes are called protists. 19. Before the era of molecular phylogeny, the four traditionally group kingdoms of Eukarya along with prokaryotes formed the so-called five kingdoms of living organisms. 20. Phylogeny is thr ordering of species into higher taxa and rhe construtof evolutionary trees based on evolutionary relationships. 21. Multicellular plants and animals are called metazoans. 22. From the comparative molecular sequencing using 16S ribosomal RNA, the three domains of life are Bacteria, Archaea, and Eukarya. 23. Fungi are unicellular, multicellular, Or coenocytic heterotrophic eukaryotic organisms which do not contain chlorophyll and which characteristically form rigid cell wall containing chintin or cellulose. Fungi are classified into  Ascomycetes  Zygomycetes  Basidiomycetes  Oomycetes  Deuteromycetes 24. Apart from Oomycetes, the remaining groups are usually found in soil and decaying plants and animals. 25. The common name for ascomycetes is sac fungi , for Basidiomycetes is club fungi, for zygomycetes is bread molds, for Oomycetes is water molds and for Deuteromycetes is fungi imperfecti. 26. The typical representative of :   Ascomycetes is saccharomyces and neurospora  Zygomycetes are mucor and rhizopus  Basidiomycetes are amanita and agaricus  Oomycetes is allomyces  Deuteromycetes are penicillium, aspagillius and candida. 27. are large heterogeneous group of unicellular and multicellular eukaryotic photosynthetic organisms. 28. Few things to know about algae:  Algae lack well developed vascular systems.  They can be autotrophic or heterotrophic and can reproduce both sexually and asexually.  Most of them are found in freshwater or marine environments while few of them are found in terrestrial habitats.  The body of an algae is called thallus. 29. The six common groups of algae are:  Chlorophyta  Euglenophyta  Chrysophyta  Dinoflagellata  Phaeophyta and Rhodophyta.  Sometimes a seventh one whose common names are stoneworts and brittlewort is added. 30. The commons name of:  Chlorophyta is Green Algae  Euglenophyta is Euglenoids  Chrysophyta is golden algae and brown diatoms  Dinoflagellata is dinoflagellates  Phaeophyta is brown algae  Rhodophyta is red algae. CHAPTER 5: Eukaryotic Protists: Protozoa — General Characteristics and Classification. KEYNOTES : 1. The genera of protozoa are unicellular eukaryotic organisms that lack cellulose cell walls and are usually colorless. 2. A large number of the genera of protozoa are found in freshwater or marine environments, and a large number of them are parasitic in other animals including humans. 3. The process by which the genera of protozoa feed by ingesting particulate materials is known as phagocytosis. 4. Phagocytosis is the process of surrounding a food particle with a portion of their flexible cell membrane to engulf the particle and bring it into the cell. 5. The genera of protozoa include but not limited to 6. Ameoba , Paramecium, and Trypanosoma. 7. Some genera of protozoa have a gullet which they use to swallow bacterial cells or smaller eukaryotic cells. E.g paramecium. 8. Based on their Morphologies and other features, protozoa are classified as Sacordina, Mastigophora, Ciliphora and Apicomplexans. 9. Protozoa that move by ameboid motion are called Sacordina. 10. Protozoans using flagella , mastigophora, cilia , ciliphora, are called Apicomplexans. 11. Apicomplexans are all non–motile and parasitic for higer animals. 12. The oral cavity and intestinal tract are the usual habitats of Amoebas. Amoeba belongs to the Sacordina group of protozoa. 13. Entamoeba histolytica is a good example of a parasitic amoeba. 14. Amoebic dysentery is caused by amoebas. 15. Foraminifera and actinophyrys are marine organisms. 16. Flagellates belong to the protozoan group of Mastigophora. 17. The most important pathogenic Mastigophora are the trypanosomes. 18. The cause of the African sleeping sickness is trypanosoma gambiense. It lives and grows in the blood stream, but later invades brhe central nervous system , causing inflammation of the brain and spinal cord. This parasite is transmitted from host to host by The Tse fly. 19. Tse fly belongs to the Glossina species. 20. Euglenoids are grouped as algae because of their chlorophyll content and other factors. 21. The ciliates belong to the Ciliphora group of protozoans. 22. Micronucleus and Macronucleus are the two kinds of nuclei of the ciliates. 23. The Micronucleus is concerned only with inheritance and sexual reproduction, while Macromolecules is involved in the production of messenger ribonucleic acid for various soexies of cell growth abd function. 24. Ciliates have tricocysts. Tricocysts are long filaments that enable thee protozoa to attach itself to surfaces and aid it in defence. 25. The common disease caused by the ciliates is dysentery. 26. Giardiasis, Leishmaniasis are other diseases caused by the flagellates. 27. The sporozoans belong to the Apicomplexa group of protozoans. 28. Sporozoans are obligate parasites and they absorbe food in soluble form through the outer wall. 29. Sporozoans produce analogous structures called sporozoites. 30. The most common diseases caused by the sporozoans are Malaria and Toxoplasmosis. CHAPTER 6 : The Viruses — Discovery, Structure , Properties and Classification. KEYNOTES: 1. Virus is a latin word which means poisonous fluid. 2. Specific agents of microbial diseases were first recognized in the 19th century. 3. In 1892, D.J Ivanowsky discovered that infectious extracts from tobaccos plants with mosaic disease retained its infectivity after passage through a filter paper capable of preventing the passage of bacteria. 4. B.W Beijernick discovered that the virus of tobacco mosaic disease could be precipitates precipitated from a suspension by alcohol without loosing its infectious power and was capable of diffusing though an agar gel. 5. W.B Beijernick concluded that virus was never a living organism but rather a fluid infectious principle. 6. 40 years later , W.M Stanley showed that infectious principle of the same virus could be crystallized and that the crystals consisted largely of protein. 7. Although, few years later , it was found that the purified tobacco mosaic did not only contain protein , but as well as a much smaller but constant amount of ribonucleic acid. 8. The infectious principle is built up from protein and nuclei. 9. The first virus to be described were agents of diseases for higer plants and animals. 10. The following are the classification and properties of viruses:  Nucleic Acid Types  Size and Morphology  Presence of Specific Enzymes  Susceptibility to Physical and Chemical Enzymes; especially Ether  IImmunologic Properties  Natural Methods of transmission  Host , tissue and cell tropisms 11. Vaccinia , measles, rubella , chicken pox, yellow fever, dengue, entroviruses, etc are examples of general diseases. 12. Poliomyelitis aseptic meningitis, rabies, arthropods, lymphocytic chroriomeningitis, perpes simplex, meningoencephalitis of mumps, measles, and virus infections are diseases of the nervous system. 13. Adenovirus, conjunctivitis, herpes keratoconjunctivitis, and epidemic hemorlafic conjunctivitis are diseases of the eye. 14. Mumps and cytomegalovirus are diseases of the salivary glands. 15. Herpes sunflex vurust, hepatitis virus, papilloma virus, molluscum contagiosum virus, the retroviruses associated with Acquired immune Deficiency Syndrome , and probably cytomegalovirus are all sexually transmitted pathogens. 16. Influenza, para influenza, respiratory syncytial virus pneumonia and bronchitis, adenovirus pharyngitis, and Common cold are diseases of the respiratory tract. CHAPTER : Plant Science and Biotechnology KEYNOTES: 1. Plants that have weak and soft stem and may be annual or biannual are known as Herbaceous. E.g Ageratum,, Emilia sonchifolia. 2. Suffretesces are under shrubs in which the basal stem is hard or woody and the remaining part of the area stem is soft. 3. The soft part of suffretesces withers during the dey season and the woody part germinates during favourable condition. 4. Cyphostema quadrandularis syn is an example of a suffretesces. 5. Plants with woody stem and have spreading branches from the basal stems and often lack main trunk are called shrubs. 6. Duranta sp, and ixora sp are examples of Shrubs. 7. Duranta sp are also called yellow bush. 8. Aborescent are trees with main trunk that later bears branches. 9. Gmelina arborea is an example of an Aborescent. 10. Herbaceous , suffretesces, shrubs and Aborescent are plants that exhibit stem habits. 11. Corm are enlarged bases of herbaceous stems which become fleshy, subterranean and upright bearing membraneous scales, leaves buds, contractile and adventitious roots. 12. The old corm gives rise to the smaller ones. E.g Cocoyam. 13. A bulb is a modified shoot. A. sativum is an example of a bulb. 14. Rhizome is an underground fleshy stem growing horizontally beneath the soil surface and guvjng off aerial shoot. 15. Zingiber officinale is an example of a rhizome. 16. Stem tubers are enlarged fleshy stems that developed into tubers. 17. Dioscorea sp is an example of a stem tuber. 18. Stolon are slender trailing stem given off by the older basal stem. Cocoyam and water lettuce are examples of a stolon. 19. Another name for water lettuce is Pristia sp. 20. Offset is similar to stolon but it gives off shoot at the apex. 21. Pistia sp and strawberry are examples of offset. 22. A Cladophyll is a soft fleshy stem in which the leaves are vestigial or modified into spines. 23. A Cladophyll stores water , and it's the major organ of photosynthesis. 24. Cladophylls are xerophytes. 25. Cactus and spurges are examples of cladophyll. 26. Another name for Cactus is Opuntia and another name for spurges is Euphorbia sp. 27. Suckers are the net and fleshy plantlets arising from the sub–aerial or basal part of a system. 28. Musa sapientum and Musa paradisciaca are examples of suckers.. 29. Musa sapientum is another name for banana , and Musa paradisciaca is another name for plantain. 30. Difuse, declined, decumbent, Prostate, Erect, Climbing or scandent, and Creeping of repent are the known adjectives for describing the direction of stem growth. 31. Diffuse means to grow in all direction. Lemons diffuse. 32. Another name for lemon grass is Cymbopogon citratus. 33. Declined means growing in a slanting position. Soda acuta grows in this manner. 34. The situation where the stem curves from base before growing upright is called Decumbent. 35. Arachis Hypogeal and Tridax procumbens grown in this manner. 36. Arachis Hypogeal is another name for Groundnut. 37. Erect simply means growing upright. Mangifera indica and Citrus sinensis. 38. Mangifera indica is another name for mango , while Citrus sinensis is another name for Sweet orange. 39. Climbing/Scandent are plants that cling to other plants for support. 40. Dioscorea sp and Mucuns pruriens are climbit or scandent plant. 41. Creeping plants are plants that creep on the ground surface producing adventitious roots on the nodes as they grow. 42. Commelina diffusa and Senna mimosoides are creeping plants. 43. The arrangements of leaves on the stem is known as phylotaxy.  44. The three basic types of phylotaxy are Alternative, or spiral leaf engagement, Opposite Lear arrangement, and Whorl or verticillate leaf enlargement. 45. Venation is the arrangement of vein on the leaf. 46. Net Or reticulate venation and parallel venation are the two basic types of venation. 47. A flower is the reproductive organ of a plant. 48. Flowers borne singly is known as solitary, while flowers borne in clusters are called inflorescence.a typical flower is made up of four floral organs. 49. Sepals, petals, adroecium/stamen and gynoecium are the four floral oragns of a topical flower. 50. Sepals are collectively called calyx, 51. Sepals are collectively ced coroa, 52. Androecium also known as stamen contains anther and filament. 53. Gynoecium also known as pistil contains stigma, style and ovary. 54. Complete flower, incomplete flower, Pistillate flower, Staminate flower, Neuter or Sterile flower, Monoecious plant, and Dioecious plants are the terms used jn describing variation in flower parts or organs.. 55. A complete flower is a flower with all the four floral parts or whorls. 56. An incomplete flower is a flower that lacks one or more of the floral part. 57. A Pistillate flower is a flower that lackss the male part. 58. A staminate flower is a flower that lacks the female part. 59. Neuter or Sterile flower is the flower that lacks both male and female parts. 60. Monoecious plants are plants that bears the male and female reproductive organs on the same plant. Maize, whistling pinr and pinus are Monoecious plants. 61. Dioecious plants are plants that bears the male and female reproductive organs on plants on separate plants. 62. Lawlawr, cycad , etc are Dioecious plants. 63. Flowers that can be divided into two equal halves from any plain is known as radially symmetrical or actinomorphic. 64. Hibiscus flower is an actinomorphic or regular flower. 65. Hibiscus flowers are radially symmetrical. 66. Flowers that can be divided into two equal halves from only one plain is called a zygomorphic or irregular floworr. 67. Pride of Barbados is an irregular floworr , it is bilaterally symmetrical. 68. Ovary and floral whorl relationship simply describes the various arrangements of the other floral whorls in relation to the position of the ovary on the flower. 69. The other floral whorls include Calyx, Corolla and Androecium. 70. A key is an analytical device for the determination of the names of known plant included in it. CHAPTER 8 : Taxonomy Of Plants KEYNOTES : 1. Taxonomy is the branch of botany that delas with the description, identification, classification and naming of plants. 2. Plants te classified: For easy reference to the plants and transmission of information, To facilitate and enhance scientific repeatability, to adequately help in the harness of the food , drugs, oil and other benefits derivable from the plants. 3. Taxonomic hierarchy is the system of arrranging plants in the hierarchical or different levels for the purpose of classification of plants. 4. The basic unit of classification in descending order are : Kingdom, Division, Class, Order, Family, genus and species. 5. Species is the basic unit of Classification. And it represents a grouo of individuals having very close resemblance to one another, structurally and functionally. 6. Species inter breed freely and give rise to progeny of the same kind. 7. Species normally have the same chromosome number. 8. Normenclature is concerned with the determination of the correct name of a plant, while the system if assigning plant species whrh two naanes is known as binomial nomenclature or binomials. 9. For instance , in Mangifera indica Linn, 10.. the first word Mangifera is the generic name , and the word indica is the specific epithet or specific name. 11. The two names are italicized because they're latin or scientific names. And the abbreviation Linn. represents the authority or the person that first named the plant. 12. The first person to name Mango as Mangifera indica Linn. was carolius Linneaus. 13. The system of classification of plants includes : 14. Artificial system of classification 15. Natural system of classification 16. Phylogenetic or cladistic system of classification 17. Phyletic system of classification 18. Phenetic system of classification 19. Numerical taxonomy 20. DNA Sequencing system 21. DNA barcoding 22. In artificial system of classification, plants may be classified based on economic reasons, length of life, and habit or habitat. 23. Natural system of classification is based on totalutttof many correlated natural characters inherent in the morphological, anatomical, genetical and physiological attributes among others. 24. Phylogenetic or cladistic system of classification is the grouping of plants with closest common ancestry or descent. 25. The approach of phyenetic system of classification is based on grouping of plants according preselected set of elevant characters. 26. Numerical taxonomy is a modern branch of taxonomy that uses Computer software to compare very large number of characters without weighting them. 27. DNA Sequencing system entails the comparison of nuclei acid sequence in the genetic makeup of an organism. 28. DNA barcoding is a taxonomic method that uses a short genetic marker in an organism's DNA to identify it as belonging to a particular species. 29. Herbanium refers to the place or house where plant specimens that have been dried, pressed and preserved are placed or collected. So herbanium materials are those materials that have been scientifically dried, pressed and preserved. 30. The following are some importance of herbanium : they're easily available for teaching and research, and they're important to those engaged in active taxonomic work. 31. Fruits,uninfected twigs with flowers , rhizome, tubers , corms, bulb, root system , etc are some items collected for the preservation of herbanium. 32. The following are equipments for he collection of herbanium samples : press nd folders, field note book, vasculum or polythene bags, sickle with long handle , and digger or trowel and orunning knife or shears. 33. The following are methods of preparing herbanium species : Drying , Mounting of the specimen on card board sheet, Labelling , Filling, and Care of the specimens. CHAPTER 9: Bryophyta : Morphology and Life Cycle. KEYNOTES : 1. Bryophytes are the first green plants whose body is either thalloid or may simply have stem–like and leaf– like structure as well as root–like structures called rhizoids. 2. Bryophytes have defined alternation of generation between two life phases– Gametophyte generation and Sporophyte generation. 3. Gametophyte is larger than Sporophyte. 4. The sporophyte is completely parasitic or dependent on the gametophyte. 5. The gametophyte bears the male reproductive organ called antheridia and the female reproductive organ called archegonium. 6. Antheridium is the singular form of antheridia. 7. The antheridium is the male reproductive organ that eventually produces the flagellated gamete or sperm cells called antherozoids or spermatozoids. 8. The archegonium produces the egg or oosphere. 9. The egg, zygote and embryo receive protectr and nourishment from the archegonium. 10. During fertilization, the flagellated spermatozoids reach the ovum/egg in the flasj shaped archegonium by swimming through the water into the ventral canal to bring about fertilization of the egg. 11. Bryophytes can be monoecious it Dioecious. 12. Liverworts, Hornworts , and Mosses are the three groups of bryophytes. 13. Ricca and Marchantia are examples of Liverworts 14. Anthoceros is an example of Hornworts 15. Funaria is an example of Mosses. 16. Liverworts are flat , green and dorsi–ventral plants with dichotomously branched thallus. 17. The thallus of liverworts is attached to the substratum by means of unicellular rhizoids. 18. Liverworts are photosynthetic. 19. Marchantia is Dioecious. I.e with male and female reproductive organs that are borne on different gametophytes or thalli. 20. The reproductive organs of Marchant are borne on the receptacles and the receptacles may be stalked or sessile. 21. The stalked receptacles are called gametophores. 22. The male gametophores are known as antheridiophores , while the female gametophores are known as archegoniophores. 23. The antheridiophores bears the antheridia on a disc–llike receptacle, while the archegonia are bornee on archegoniophore. 24. Marchantia reproduces by vegetative reproduction and by sexhal reproduction. 25. Vegetative reproduction also means asexual reproduction and it is by fragmentation and gemmae cup. 26. Marchantia is also known as Liverworts. 27. The leaves of the moss plant are green and photosynthetic. The basal part of the leafy shoot bears the root–like structures called rhizoids. 28. Rhizoids are used for the absorption of nutrients from the substrate. 29. Rhizoids give rise to Vegetative structures called protonema, gemmae cup, bulbil or buds. 30. Funaria is monoecious. I.e the reproductive organs are borne in the same plant. 31. The antheridia and archegonia are normally borne on separate branches. This condition is known as autoicous. 32. Funaria reproduces by sexual reproduction and by asexual or vegetative reproduction through protonema, gemmae cup, and bulbils or buds. CHAPTER 10: PTERIDOPHYTA: MORPHOLOGY AND LIFE CYCLE KEYNOTES: 1. The Filicales , Lycopodiales Lycopodium, Selaginellales, and Equisetinales make up the pteridophyta group. 2. The Filicales are also known as the ferns 3. The lycopodiales are also known as the lycopods, while lycopodium is also called club moss. 4. Selaginella is an example of Selaginellales 5. Dryopteris and Nephrolepis are examples of Filicales. 6. Equisetum is an example of Equisetinales. 7. Plants in this group possess the conducting vascular tissues which are made up of Xylem and Phloem. 8. Pteridophytes are called Cryptograms because when their reproductive processes are compared with those of the flowering plants, they appear hidden. 9. Saprophytes have distinct true shoots and roots which help them to adapt to terrestrial environments. 10. Some ferns are epiphytes on palms and other trees. 11. Ferns are made up of rhizomes bearing fibrous adventitious roots and large aerial leaves, spirally arranged along the axis. 12. Compound bi-pannate leaves have numerous, brown dry scales called ramenta at their bases. 13. Compound bi-pinnate leaves are divided into leaflets which are further subdivided into pinnules. 14. Leaflets are also called pinnae. 15. Petiole is attached to the rhizome , while pinnules and pinnae are attached to the petiole. 16. The very young leaves with the rachis, pinnae and pinnules are spirally coiled in circinnate fashion. 17. This folding is a primitive character found in many pteridophytes. 18. Each pteridophta leaf takes two years to develop. 19. One of the characteristics of ferns is that all young leaves and the bases of old leaves are covered with brown ramenta. 20. Dryopteris reproduces by spores as well as vegetatively. 21. The spores are found in the sporangia which occur in clusters or sori on the abaxial faces of the mature pinnules. 22. Each sorus is protected by the indusium which is kidney-shaped. 23. The sporangia arise from a central protuberance on the pinnule called placenta. 24. A ripe sporangium is an ovoid, hollow structure borne on a multicellular stalk which often bears a grandular appendage that stores water. 25. When the sporangium is ripe, the unicellular , homosporous spores are dispersed under warm dry conditions. 26. Under a damp shady environment, the spores will germinate to produce rhizoids and a short filament of cells. 27. Any part of the fern , rhizome , leaf or root can reproduce vegetatively to produce a new plant. 28. The archegonia develop behind the apical notch while the antherida are scattered among the rhizoids lower down. 29. The antherida produce motile antherozoids with a group of very long flagella. 30. The antherozoids are released before the maturity of the archegonia to reduce self fertilization. 31. In the case of the Bryophytes, the archegonia develpe the oosphere inside the venter but twith the ventral canal cell, the neck canal cell and the neck underneath. 32. At maturity, the ventral canal cell and the neck canal cells disintegrate, while the tip ruptures a mucilage-filled passage leading to the oosphere. 33. The antherozoids make chemotic movement in response to the malic acid secreted by the neck cells. Then, they swim to the neck of the archegonium and fuse with the oosphere to form the oospore. 34. The phenomenum where the Sporophyte developes from the prothallus without gamete formation is known as apogamy. 35. The phenomenum where by the gametophytes develop from a sporophyte without spore formation is known as apospory. 36. Both apogamy and apospory are methods of vegetative reproduction 37. Vegetative propagation occurs when a horizontal rhizome gives rise to adventitious buds or branches which separate as the older parts of the rhizome dies. 38. This vegetative propagation can take place either in sporophyte stage or in the gametophyte generation. 39. Selaginella is slender, much branched and creeps on the walls or on the ground. 40. The slender stems of the selaginella bears 2 rows of leaves on the upper surface , and two rows of larger leaves on at the two sides. 41. The vascular system of the stem of a selaginella is usually protostele. 42. Selaginella has rhizosphore. 43. Rhizosphore is also known as root bearer. 44. Sporophytes are heterosporous. 45. Microspores and megaspores are the two spores the sporophytes bear. 46. Sporophytes reproduces asexually and bears microsporophylls and megasporopgylls. 47. The two sporophylls may be borne on the same plant or two spate plants. 48. Microsporangium undergoes reduction division to produce 64 microspores. 49. The sporangia consists of short, stout stalk and the capsule. 50. The micro and mega spores germinate to give rise to male and female prothalli. 51. Prothalli are the micro and mega gametophytes which bears the male gametes and the female gamete 52. The male gamete is also called antherozoids while the female gamete is known as the egg-cell. 53. When the male and female gametes fuse, the biciliate antherozoids swim to the megaspores while the megaspores are still retained in their sporangia. Then they enter the archegonia and fertilize the eggs. 54. The Oospore undergoes division and forms a suspensor and an embryo 55. The Oospore is also known as the embryo. 56. When the megaspore falls , the embryo forms a root, stem, two cotyledons and leaves and develops into an independent sporophyte. 57. All the stages from the zygote/Oospore to the spore mother cells are the sporophytic generation, while all the stages from the spores, micro and mega sporangia to the gametes represent the gametophyte generation. CHAPTER 11: MORPHOLOGY AND LIFE CYCLES OF THE SPERMATOPHYTA  KEYNOTES: 1. Taxonomists are scientists who specialize in classifying living organisms systematically based on certain characteristics. 2. Members of the plant kingdom are grouped into Cryptogams and Phanerogams Or Spermatophyta. 3. The Cryptogams neither bear fruits or flowers and they reproduce by simple fission or by some minute structures called spores. 4. Thallophyta, Bryophyta, and Pteridophyta are the three groups of Cryptogams. 5. Algae and fungi are examples of Thallophyta. 6.