Structure Meets Function

How do perfect flowers avoid self-pollination?

FLOWER REPRODUCTION

Students will be able to:• Recognize the processes that allow organisms to reproduce sexually.• Identify the role of a flower in plant sexual reproduction.• Explain the mechanisms flowers have to avoid self-pollination.

Sexual Reproduction• The process that allows the union of gametes from two different individuals.

Major cellular processes

•Meiosis: Cell division which produces haploid (1N cells)N=number of chromosomes

• Fertilization: Union of gametes to produce a zygote (2N)

Why sex?• Mutation is the ultimate source of genetic variation.

• Sex shuffles up combinations of mutations!

Flowers aid in sexual reproduction

Fertilization in a flower

Lab Activity• How does a plant avoid self-pollination?

• You will observe the structure of a perfect flower.

• You will analyze how the structure allows for the function of cross-pollination (avoiding self-pollination).

Questions to ponder:

• Does timing prevent self-fertilization?• Do the male and female structures prevent accidental self-

fertilizaiton?