Plant
Reproduction
Asexual and Sexual
(yes, sexual!)
Asexual Reproduction

Most plants reproduce asexually
 Does not require fertilization
 faster and requires less energy
 Results in clones of the parent plant
 genetically identical

Vegetative propagation – a type of asexual reproduction in
which new plants grow from nonreproductive plant parts
Vegetative Propagation

Stolons – runners from the stems of parent plant produce
buds which grow into new plants
 crabgrass, aspen trees, strawberries
Vegetative Propagation

Rhizomes – specialized stems that grow underground
 bamboo and sumac trees
Sexual Reproduction



Usually requires two parent plants
Generates diversity in offspring
Flowers – reproductive structures in angiosperms
Flower Anatomy
Flower parts are arranged in 4
concentric whorls
1. Sepals – protect flower from
damage when it is a bud
2. Petals – attract pollinators
 often very colorful
Flower Anatomy
3. Stamens – male structure
that produces pollen
 Anther – tip of stamen

meiosis produces
spores

develop into pollen
grains (contain
sperm cells)
 Filament – supports
anther
Flower Anatomy
4. Pistil – female structure that
produces ovules
 Stigma – sticky tip that
receives pollen
 Style – narrow structure
that leads pollen to
ovary
 Ovary – develops into
fruit and produces eggs
in ovules

ovules develop into
seeds
Flower Anatomy

Flowers may or may not have all four of the basic flower parts




Complete – has all four flower parts
Incomplete – lacks any one of the four parts
“Perfect” flowers – has both stamens (male) and pistils (female)
“Imperfect” flowers – lack either stamens or pistils
Sexual Reproduction

Steps in Sexual Reproduction
1. Maturation of ovules
2. Pollination
3. Fertilization
4. Seed germination
Pollination
Pollen is transferred from an anther to a stigma
Pollination

Pollen can be carried by:
 Wind
 Water
 Insects
 Birds
 Bats
Fertilization
Fertilization – When the sperm and egg unite. Occurs inside the
ovule. The zygote develops into the embryo.
Another sperm fertilizes polar nuclei to form endosperm (food
storage)
Germination
Germination – A plant emerges from the seed and begins to
grow
Germination
Conditions necessary for seed germination
 Proper temperature
 Water
Steps in Seed Germination
1.
Seed absorbs water and swells
2.
Primary root develops
3.
Shoot begins to grow
4.
Cotyledons begin to shrivel
Review
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Pollen develops
Pollination occurs
Upon pollination, stigma sends out pollen tube that grows
through the style to the ovary
Sperm enters ovule (contains egg) – site of fertilization
One sperm fertilizes egg and forms zygote
Another sperm fertilizes polar nuclei to form endosperm
(food storage)
Zygote becomes plant embryo
Ovule becomes seed
Ovary develops into fruit that surrounds seed
Click here for BrainPop Pollination Animation