seedless plants bio exam 3

bryophytes

liverworts, mosses, hornworts, seedless, dominant gametophyte generation

tracheophytes

lycophytes, ferns, seed plants, vascular structures, dominant sporophyte generation

lycophytes and pterophytes

lycophytes (sister to all other vascular plants), pterophytes(ferns and their close relatives), emphasizing their sister relationship, variety (referring to the diversity within vascular plants)

issues plants had to overcome

water loss, protection from harmful effects of the sun, dissemination of gametes, overall plant growth and repoduction

Green Algae Clades and Land Plants

chlorophytes (never made it to land), charophytes(sister clade to all land plants), strephtophytes (charophytes and land plants)

diploid stages (multicellular haploid and diploids stages)

reduced haploid stage and trend towards diploid embryo protection

Adaptation to terrestrial life

waxy cuticle and stomata, moving water within plants = protection from drying out, UV radiation caused mutations = shift to dominant diploid generation so recessive mutations are masked

bryophytes

small, lack vasculature

tracheophytes

xylem moves water, phloem moves sugar and nutrients,

sporophytes

multicellular diploid stage, sporophyte (diploid spore mother cells), spores made by meiosis (produce 4 haploid spores),

gametophyte

multicellular haploid stage, spores divide in haploid (mitosis), spores produce gametes, diploid zygote is the first cell of the next sporophyte generation

roots and stems

early seedless plants show stems but not roots and leaves which limited their size cause without roots, the plants would fall over and not get enough water

tracheophytes

have xylem and phloem, true roots only found in tracheophytes