How Do Flowers Reproduce Sexually?

Flowers have the sole function of reproduction.

While beautiful to behold, flowers are designed solely to reproduce the plant. They usually have both male and female reproduction organs, roughly similar to human sexual organs. In reproduction, most plants must spread pollen to other flowers to make seeds.

Pollinators

Flowers begin the reproduction process by attracting bees, butterflies and other pollinators through their brightly colored petals, scents and locations on stems that wave in the air. Pollinators enter flowers to gather pollen and nectar.

Male Reproductive Organs

Filaments holding anthers and pollen

Most flowers have both a stamen, the male flower part, and a pistil, the female flower part. The stamen consists of paired anthers, sacs which hold pollen -- the male reproductive cells, or sperm -- on long, thin stalks, called filaments. As pollinators move around in a flower, pollen sticks to their legs or underside of their bodies.

Female Reproductive Organs

A style and stigma

Pollen is distributed to female reproductive organs as pollinators visit other flowers. The pistil has three parts: a stigma, style and ovary. The stigma is the sticky surface at the pistil's top, which holds pollen from pollinators' bodies. The tube-like structure that supports the stigma is the style, which leads down to the ovary. The ovary contains ovules, or egg cells.

Fertilization

In the fertilization process, pollen travels down the style from the stigma, enters the ovary, and joins with an ovule, fertilizing it. The fertilized ovule is the plant's seed. When the seed sprouts, reproduction is completed.

References

• University of Arizona College of Agricultural and Life Sciences: Parts of Flowers
• Arizona State University Cooperative Extension: Master Gardener Manual--Botany: Plant Parts and Functions

Resources

• Teachers' Domain: The Reproductive Role of Flowers