lec 18 & 19 evolution of plants and non vascular and seedless vascular plants

what are 4 shared characteristics between charophytes and land plants?

both multicellular, eukaryotic, photosynthetic, autotrophic, cell walls of cellulose, many biochemical details

what are 4 distinct characteristics between charophytes and land plants?

only land plants have alternations of generations, walled spores to produce in sporangia, multicellular gametangia, and apical meristems

why do most bryophytes grow close to the ground and are restricted to moist environments?

they don’t have vascular tissue and have rhizoids instead of roots

describe 3 traits that characterize modern vascular plants and explain how these traits conributed to success on land

they have vascular tissues called xylem and pholoem. they also provide structural support and allow it to grow tall. seedless vascular plants have flagellated sperm

how are vascular plants different from bryophytes?

vascular plants have the vascular tissues which provide structural support and the xylem and phooem. bryophytes have no roots or vascular tissue and get water and nutrients from the air

what adaptations allowed plants to colonize the land?

charophycean ancestors (green algae) lives at the water’s edge where they had access to unfiltered sun, more CO2 and nutrient rich soil. the layer of durable polymer (sporopollenin) prevented the exposed zygotes from drying out

sporangia

haploid spores that sporophyte produces

gametangia

gametes produces within organs

archegonia

female gametangia that produce eggs and are the site of fertilization

antheridia

male gametangia and are site of sperm production and release

apical meristems

where plants sustain continual growth

gymnosperms

“naked seed” plants, including conifers

angiosperms

the flowering plants

microphylls

leaves with a single vein

megaphylls

leaves with a highly branched vascular system