BIOL 150 Lecture Notes - Lecture 15: Green Algae, Gametophyte, Sporophyte
Document Summary
Sessile (i. e. don"t move) (issues: nutrient acquisition, seasonal adaptation, defenses) Plants were the first organisms to emerge onto land (sequence: plants, then insects, then vertebrates) Only photosynthesis can convert energy and co2 into organic matter. Live in marine, freshwater and otherwise moist environments. Plants make transition to land at 475 mya: origin (475 416 mya): Were probably mainly algal: silurian-devonian explosion (416 359 mya): Seedless vascular plants dominated: carboniferous (359 299 mya): Most fossils are from seedless vascular plants: diversification of gymnosperms (299 145 mya): Were dominant: diversification of angiosperms (145 present) All seed plants and most non-seed plants produce spores of different types and sizes (referred to as. Homospory is the production of one kind of spore; can develop into either male or female spores. Variation among lineages in which stage (sporophyte and gametophyte) is dominant (50 50) Thick walls of cellulose and lignin (to defy gravity) Waxy outer coating prevents water loss.
