Transcript Angiosperm Reproduction Chapter 38

Angiosperm Reproduction
Chapter 38
Parts of a Flower
Stigma
Stamen
(male)
Anther
Filament
Style
Ovary
petals
ovule
sepal
Carpel/
Pistil
(female)
Sperm Formation
Anther contains the
microsporangia
Microsporangia (2N) creates
4 haploid microspores by
meiosis
Each microspore will
undergo mitosis to
make a generative cell
and a tube cell
Generative cell goes
through mitosis to create
2 sperm
Pollen = male
gametophyte
Gametes (2
sperm) formed
by
gametophyte
Egg Formation
Megasporangia
divides by meiosis
to create 4 haploid
megaspores
3 megaspores
die
Female gametophyte
3 mitotic divisions
3 Antipodal cells
2 Polar nuclei
2 synergids
egg
Double Fertilization of ovule
Pollen containing
2 sperm and 1
tube cell
1. Tube cell
creates a
pollen tube
down the style
until it reaches
the micropile
2. The 2 sperm
follow the path
of the tube to
the egg
5. Ovule is now a
seed; the ovary
develops into a fruit
3. One sperm fertilizes the
egg, creating a diploid
zygote
4. 2nd sperm fuses with the 2 polar
nuclei, creating a 3N nucleus. This
divides and forms the “endosperm” =
nourishment and food for the zygote
Fruit assists in seed dispersal
and protects the seed with the
developing embryo
Seed Structure
plumule
Monocot Seed
epicotyl
Mono = one
Cot = Cotyledon
hypocotyl
One cotyledon
Radicle = embryonic root
epicotyl
hypocotyl
Dicot Seed
plumule
Di = two
Cot = Cotyledons
(Seed Leaves)
Two cotyledons
Radicle  Root
Hypocotyl  Shoot
Epicotyl  Shoot Tip
Plumule  Young Leaves
Germination
Plumule (foliage)
epicotyl
Cotyledons
Cotyledons
hypocotyl
hypocotyl
Integument (Seed coat)
radicle