Ch.25-26 Plants and Seed Plants Flashcards
charophytes
closest living relative to land plants
alternation of generations
gametophyte is haploid and produces haploid gametes by mitosis
fusion of gametes gives rise to the diploid sporophyte which produces haploid spores by meiosis (diploid to haploid)
vascular plants
vascular tissue used to transport H2O and nutrients
bryophytes
non-vascular plants
- liverworts
- mosses
- hornworts
spores (2n sporophyte)
n- gametophyte (dom) larger and longer
anchored to substrate by rhizoids, no roots
height constrained by lack of vascular tissue
vascular tissue composed of
xylem and phloem
xylem
conducts most water and minerals (roots up)
phloem
distributes sugars, amino acids, and other organic products ( products of photosynthesis down)
Life Cycle with Dominant Sporophytes
unlike bryophytes, sporophytes of seedless vasc. plants are the larger generation
gametophytes are tiny plants that grow on or below the soil surface
flagellated sperm
seeds
consists of an embryo and its food supply with protective coat
Gymnosperms
naked seeds that are not enclosed in chambers
Angiosperms
seeds that develop inside chambers called ovaries
have reproductive structures like flowers and seeds
terrestrial adaptations of seed plants
- reduced gametophytes, are microscopic internal to sporophyte
- seed forms in ovules
- pollen contains cells that become sperm
ovule
consists of an egg producing female gametophyte surrounded by a protective layer of tissue called the integument
female gametophytes develop from
large megaspores
male gametophytes develop from
small microspores
