BIOL1012 Lecture Notes - Lecture 13: Ascocarp, Glomeromycota, Archegonium
Document Summary
Gymnosperms: one of the two major groups of seed plants, bear naked" seeds, i. e. , not enclosed in ovaries, seeds are exposed on the sporophylls, which are modi ed leaves (bearing sporangia) that are typically clustered to form cones. Diversity: four major groups, cycadophyta, gnetophyta, ginkgophyta, coniferophyta (conifers) Dominate in the harsh colder climates of the. Canada"s boreal forest accounts for 35% of our land area and 77 % of our total forest area http://atlas. nrcan. gc. ca/site/english/ learningresources/theme_modules/borealforest/ forest_regions. jpg/image_view. Angiosperms: the second" major group of extant seed plants, produce owers and seeds in fruits (i. e. , seeds enclosed in mature ovaries) Angiosperm evolution: oldest angiosperm fossils are about 140 million years old and originated during the early cretaceous, which was dominated by gymnosperms, had explosive diversi cation and dominated many terrestrial ecosystems by the late. Cretaceous (100 million years ago: their key innovations offered a substantial selective advantage.
