Plant Reproduction, Growth, and Development Flashcards
(35 cards)
what is the transition to land?
moving gametes and offsprings through air
Air is […] buoyant than water, provides a […] buffer against changes in temperature and ultraviolet radiation, and […] the risk of drying out.
less, poor, increases
key adaptations for terrestrial habitats (4)
- alternation of generations
- production of spores that resist desiccation
- gametes that resist desiccation/mechanical damage
- embryo retained by/nourished by parent plants (embryophytes)
plantae
- algal sister groups of land plants
- chlororphyta
- charophyte
- have one multicellular
what groups are the seed plants?
- gymnosperms and angiosperms
- pollen seeds
what are lycophytes and germs and horsetails
spore dispersing vascular plants
what are the 4 major steps of a life cycle?
- formation of two types of spores
- spores undergo mitosis/meiosis inside sporangia
- pollination
- maturation of fertilized ovule into seed
what are the 2 formations of spores?
male gametophyte = male gametes
female gametophyte = female gametes
which spore undergoes mitosis inside sporangia
female: a single haploid spore develops into female gametophyte
which spore undergoes meiosis inside sporangia?
male: large numbers of haploids spores each develop a male gemotophyte
explain ovule cones
they are basically found in upper branches of gymnosperms, produce spores that become female gametophytes
where do female gametophytes develop?
ovule cones
ovule cones steps
- within each sporangium 1 cell undergoes meiosis to make 4 haploid spores
- 3 spores degrade and 1 becomes gametophyte through mitosis
- one or more haploid cells of gametophyte forms egg
- gametophyte remains attached to sporophyte
what does a pollen represent
- male gametes/gametophyte
what is a sporonpollenin
it protects the spores/pollen from uv radiation and desiccation when its in the air or water…
sporophyte
a plant that makes spores
which is a diploid multicellular plant
gametophyte
it is a haploid multicellular plant that produces games aka a plant that makes gametes
how do bryophytes release sperms
usually though raindrops and they go into the female gamete (reproductive system) and coat moist surfaces
what do raindrops do
they signal the presence of surface water and their impact can splash sperm farther than they can swim on their own
for bryophyte where and how does a sporophyte grow?
in the original female gamete (gametophyte), grows from the egg after fertilization
when do sporangia of bryophytes usually release?
their spores only release when the air is dry
what is the significance of the multicellular sporophyte?
it enhances the ability of plants to disperse on land
xylem and phloem develop only in?
sporophyte
ferm gametophytes are usually?
unisexual