Ch. 38 Angiosperm Reproduction Flashcards
big ideas: alteration of generations, parts of male/female flowers, double fertilization, parts of a seed, what a fruit is, pollination
what is the function of sepals?
to enclose and protect the bud of a flower
what is the function of petals?
to attract pollinators by size/colour/shape
what are the components of the stamen?
the anther and filament
what is the function of a stamen?
to produce pollen grains, which contain the male sex cells of plants
what are the four components of the carpel?
style, ovary, ovule, stigma
what is the function of the plant ovary?
to house ovules, which will become the seed of the plant once fertilized
what is the function of the plant ovules?
to house the egg cells and receive pollen from angiosperm pollen grains, will make the seed once fertilized
what is the function of the style?
to serve as the “bridge” between the ovary and stigma
what is the function of the stigma?
to act as a landing platform for sperm, which then travel down the style
what are complete flowers?
flowers with all 4 floral organs = bisexual = may be able to self fertilize (M AND F)
what are incomplete flowers?
flowers that lack a particular reproductive organ. may be unisexual (M OR F)
what is a monoecious plant?
a plant with both types of unisex flowers
what is a dioecious plant?
a plant which only has one sex (all male or female flowers)
what do sporophytes produce?
spores in the form of megasporocytes [female] and microsporocytes [male]
what is a composite flower?
a flower composed of multiple smaller flowers aggregated together [sunflowers/daisies]
what are the two phases angiosperm plants go through in alternation of generations?
-sporophyte [2n] and gametophyte [n] phases
what do microsporocytes produce? is it using mitosis or meiosis?
2n microsporocytes produce n microspores through meiosis
what do microspores produce? do they use mitosis or meiosis?
-n microspores produce male gametophytes [pollen grains - n] through mitosis
what do male gametophytes produce?
gametes - sperm cells which are 1n
what do megasporocytes produce, and is it through mitosis or meiosis?
megasporocytes [2n] produce megaspores [n] through meiosis
what do megaspores produce, and is it through mitosis or meiosis?
megaspores produce female gametophytes [n] - embryo sacs - through mitosis
what happens to the ovary and ovule upon fertilization?
the ovary becomes the fruit; the ovule becomes the seed
what is the function of the egg?
to fuse with 1 of the 2 pollen sperms to make a zygote
what is the function of polar nuclei?
to fuse with 1 of the 2 pollen sperms to produce the endosperm
what is the function of the synergids?
to guide the pollen sperm cells to the egg + polar nuclei
what 8 cells are formed by the megaspore’s embryo sac?
1x egg
2x polar nuclei
2x synergids
3x antipodal cells [unknown function]
what is pollination?
the transfer of pollen from anther to stigma
what are pollinators?
animals that facilitate the transfer of pollen from the anther to the stigma - butterflies, bees, bats, moths, flies, etc
what are the 3 components of a fertilized seed?
seed coat - protects the seed
embryo - develops from zygote
endosperm - provides food
how does the endosperm differ in monocots and eudicots?
monocots - endosperm stays in seed
eudicots - endosperm becomes 2x cotyledons
what is seed dormancy?
a state of low metabolic rate (no growth / development) until the right environmental conditions occur
what is germination?
the breaking of the seed coat by the seed, depends on imbibition
what is the radicle?
the part of the plant embryo that becomes the primary root - will be the 1st to leave the seed
if the radicle is the 1st structure to leave the seed, what is the 2nd?
-hypocotyl in eudicots
-coleoptile in monocots
what is the function of the fruit?
to protect and disperse seeds
why does fruit only develop for pollinated flowers?
no pollination = no seed = nothing to disperse = no point making a fruit
