Sexual Reproduction in Flowers

How do plants get fertilized? Pollination: the transfer of the male gametes to the female ovules. After pollination occurs, fertilization happens inside the flower (internal fertilization) and the ovules grow into seeds within a fruit.

Types of Pollination in Flowers

Sexual Reproduction in Flowers Petal: The parts of a flower that are often conspicuously colored. Stamen: The pollen producingpart of a flower, usually with a slender filament supporting the anther. Anther: The part of the stamen where pollen is produced. Pistil: The ovule producingpart of a flower.

Male Parts of a Flower: Stamen Stamen - male reproductive organ of a flower. It produces the pollen. Has two parts: Anther - the part of a stamen that produces sperm nuclei by meiosis. Sperm nuclei are enclosed by pollen grains. Stalk (or filament) - Holds anther up. Pollen – fine, powdery, microscopic grains, each containing a male gamete

Female Parts of a Flower: Pistil Pistil: The ovule producing part of a flower. The ovary often supports a long style, topped by a stigma. The mature ovary is a fruit, and the mature ovule is a seed.  Stigma: The top part of the pistil that has a sticky surface where pollen is deposited and germinates.  Style: long, slender stalk that connects the stigma and the ovary. Ovary: The enlarged basal portion of the pistil where ovules are produced.

Parts of a Flower Petal: The parts of a flower that are often conspicuously colored.  Receptacle: The part of a flower stalk where the parts of the flower are attached.  Sepal: The outer parts of the flower (often green and leaf-like) that enclose a developing bud.  Peduncle: The stalk of a flower. 

Pollination Pollen must first land on the stigma, travel down the pollen tube to the ovules Then fertilization takes place

What happens when an ovule is fertilized? When pollen fertilizes the ovule, the nuclei fuse and form a zygote. The zygote divides to become an embryo Embryo is encased in a seed.

How do flowers get pollinated? Wind Insects Birds animals

Why are petals so pretty?

Why are pollinators important? More rliable than the wind. Less random. Some flowers have developed specialized structures to lessen chance of self-pollination

After fertilization Sepal, petals, stamens  wither and drop off Ovary  Becomes the fruit Ovary wall  becomes fruit wall Ovule  seed Integuments  seed coat Fertilized egg  embryo

Why make a fruit? Attract animals to take fruit, dispersing seeds Dispersing seeds prevents overcrowding and competition for resources Allows possibility to colonize new areas

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What happens to the seed?