bio exam 3 seedless plants

features shared by chlorophytes, carophytes, and plantae

• multicellularity

• cellulose cell walls

• chloroplasts w/ same pigments

• starch storage molecule

characteristics carophytes share with plantae

• flagellated sperm (liverworts)

• cellulose synthesis proteins (rings)

• cytokinesis process (cell plate formation)

• sporopollenin

what is sporopollenin?

a durable polymer that protects zygotes in charophytes, spores in seedless plants, and pollen grains in seed plants

what is alteration of generations?

there are 2n and n multicellular forms in the plant’s life cycle, allows sporophyte (2n) to make large number of diverse offspring

charophyte life cycle

only haploid is multicellular, zygote does meiosis to produce 4 offspring

walled haploid spores

protected by sporopollenin, dispersed through air, made with multicellular sporangium

what is multicellular gametangia?

• protect sperm with antheridium

• protect egg with archegonium

how are sporophyte embryos nourished?

placental transfer cells within female gametophyte

what are apical meristems?

continuously dividing cells, roots and shoots grow towards resources

waxy cuticle purpose

waxy coat stops desiccation, pores allow CO2/O2 exchange, controllable stomata in most plants

secondary compounds purpose

chemicals that deter, repel, or poison competitors, herbovores, and parasites

what are mycorrhizae

in mutualism with fungi that help with water and mineral absorption

what are bryophytes?

• liverworts, phylum heptophyta

• mosses, phylum bryophyta

• hornworts, phylum anthocerophyta

bryophyte haploid form characteristics

• haploid gametophyte is dominant form

• make eggs & flagellated sperm

• most small and low growing in moist areas

bryophyte characteristics

• lack vascular and supportive tissue

• very thin body that depends on diffusion

• rhizoids for attachment (not true roots)

bryophyte diploid from characteristics

• diploid sporophyte depends on gamteophyte for food

• grows within archegonium of gametophyte

• sporangium makes many haploid spores