organismal biology Flashcards
(246 cards)
Plants evolved from what color algae?
green
how many known plant species are there?
at least 375,000
what do plants do for the planet?
supply oxygen, food and habitat for all other terrestrial organisms
the closest relatives of land plants
charophytes (green algae)
morphological traits that land plants share with charophytes
cellulose-synthesizing membrane proteins arranged in rings, structure of flagellated sperm, and formation of phragmoplast during cell division
plants move to land provided benefits such as:
unfiltered sunlight, plentiful CO2, nutrient rich soil, and few herbivores
challenges that plants had moving to land
scarcity of water and no structural support
a polymer that prevents zygotes from drying out
sporopollenin
coats charophytes
sporopollenin
found in plant spore walls
sporopollenin
traits that are in land plants but arent in charophytes
multicellular,dependent embryo; walled spores produced in sporangia, and apical meristems
two multicellular stages that plants alternate between
gametophyte and sporophyte
produces haploid gametes by mitosis
gametophyte
produces haploid spores by meiosis
sporophyte
fusion of gametes given rise to the diploid
sporophyte
nutrients are transferred from parent to embryo through what
placental transfer cells
why are land plants called Embryophytes?
the dependency of the embryo on the parent
sporophyte produces spores in multicellular organs called what
sporangia
localized regions of cell division at the tips of the roots and shoots
apical meristems
what makes plants resistant to harsh environments
sporopollenin in spore walls
when do plant spores first appear in the fossil record
470 million years ago
mosses and other nonvascular plants have life cycles dominated by
gametophytes
Bryophytes are represented by what three phyla
phylum Hepatophyta, Bryophyta, and Anthocerophyta
what phylum is liverworts in?
phylum Hepatophyta