Lifecycle Complete Flashcards
Phylum Hepaticophyta Sexual Lifecycle
Liverworts
Starts with male and female plants or, antheridiophore and archegoniophores. Gametangia produce gametes, antheridia make sperm and archegonia make eggs. It then rains and sperm swim to the eggs so that fertilization can occur. The sporophyte grows in the archegonium. This includes foot, seta, capsule, and a calyptra. The sporocyte then creates spores via mitosis. The capsule opens and elaters twitch to expel the spores. The spores germinate and male or female gametophyte.
Phylum Bryophyta Sexual Lifecycle
Mosses
These are monoecious plants, the antheridia make sperm and archegonia make eggs. It then rains and sperm swim to archegonia via the neck canal. The fertilization results in a sporophyte zygote. The sporophyte zygote does mitosis. The sporophyte creates spores via meiosis. The calyptra and the operculum fall off. Spores are released through the peristome. Spores germinate into protonema. The protonema grows leafy buds and the buds grow into gametophyte plants.
Phylum Psilophyta Sexual Lifecycle
Sporangia create spores via meiosis. Spores germinate into gametophyte plants. Gametophyte plants make antheridia and archegonia. Antheridia create sperm and archegonia create eggs. It then rains. Sperm swim to the eggs and fertilization occurs in the archegonium. Sporophyte zygote does mitosis creating foot and rhizome. Rhizomes grow vertical stems which mature into sporophyte plants.
Ground Pines Sexual Lifecycle
Whisk ferns
Sporangia create spores via meiosis. Spores germinate into gametophyte plants. Gametophyte plants make antheridia and archegonia. Antheridia create sperm and archegonia create eggs. It then rains. Sperm swim to the eggs and fertilization occurs in the archegonium. Sporophyte zygote does mitosis creating foot and rhizome. Rhizomes grow vertical stems which mature into sporophyte plants.
Phylum Lycophyta
Ground Pines Sexual Lifecycle
Adult sporophyte creates strobili. The strobili create sporophylls. Sporangia grow in the axillae and create spores via mitosis. The spores develop in gametophyte plants and develop antheridia and archegonia. The antheridia make sperm and the archegonia make eggs. It rains and sperm swim to archegonia. Fertilization occurs and the sporophyte zygote does mitosis. The zygote then matures into adult sporophyte.
Phylum Lycophyta
Spike Mosses Sexual Lifecycle
Adult sporophyte creates strobili. The strobili create sporophylls. Sporangia grow in the axillae of the sporophylls. Microsporangia create microspores and megasporangia create megaspores. The spores escape. Microspores mature into a male gametophyte and the megaspores mature into a female gametophyte. The male makes sperm via antheridia. The female makes sperm via archegonia. It rains and sperm swim to archegonia to fertilize the egg. Sporophyte zygote does mitosis and matures into an adult plant.
Phylum Equisetophyta
Horsetails and scouring rushes
Adult sporophytes create strobili. Strobili develops sporangia. Sporgania create spores (with elators) via meiosis. Spores germinate and grow into adult gametophyte plants. Some gametophytes are male and some gametophytes are monoecious. Antheridia create sperm and archegonia create eggs. It rains and sperm swim to eggs. Fertilization occurs in the archegonia. The sporophyte zygote does mitosis and grows into an adult sporophyte plant.
Phylum Polypodiophyta
Adult sporophyte develops sori under fronds. Mature sporangia releases spores. Spores germinate into gametophyte prothallus. Prothalli create antheridia and archegonia. Antheridia create sperm and archegonia create eggs. It rains and sperm swim to fertilize eggs. The sporophyte zygote grows into adult sporophyte plant.
Phylum Pinophyta
Adult sporophyte creates both pollen cones and seeds cones. Microsporocyctes create many microspores via meiosis and Megasporocytes create 4 megaspores via meiosis. Microspores create 4 cells and 2 air sacs, which are the immature male gametophyte. 3 of 4 megaspores die and the last one develops into a mature female gametophyte. Pollen grains are carried by the wind and stick to the pollen drop. The pollen is drawn in through the micropyle. The pollen germinates, 2 cells create a pollen tube which grow to the megasporangium and 1 cell divides into a sterile cell and a spermatagenous cell. The spermatagenous cell creates 2 sperm cells. The mature male gametophyte with 2 sperm cells and a pollen tube contact the archegonium. Fertilization occurs and the zygote grows into embryo, then growth is suspended. The sporophyte adult creates a seedcoat and wing for the seed. The seed escapes and is carried by the wind.
Angiosperm Female Gametophyte
In an ovule of a flower, a megasporocyte develops. It then goes through meiosis to create 4 megaspore nuclei. The cell grows a lot and 3 nuclei degenerate. The megaspore nucleus does mitosis 3 times resulting in 8 nuclei. They assort themselves. 3 migrate to the top to become antipodals, 2 in the middle become endospoerm, and 3 on the bottom are an egg and 2 synergids.
Angiosperm Male Gametophyte
Many microsporocytes undergo meiosis make 4 microspores each. The microspores separate. Each microspore does mitosis resulting in one generative cell (future sperm) and one vegetative cell (future pollen tube). A double wall develops. Pollen is released and transported by a pollinator and adheres to stigma. If attached to a proper stigma, pollen will germinate. The pollen tube grows to ovule and the generative cell does mitosis.
Angiosperm Fertilization
Pollen tube grows to ovule and into micropyle. Each sperm enters a different synergid. Sperm from one synergid enters egg. Other sperm fuses with central cell nucleus. Endosperm nucleus does mitosis and develops into a fleshy nutritive endosperm. Embry develops and then goes dormant.
