The Process of Reproduction in a Flowering Plant

Flower's Purpose

Flowering plants bring color and fragrance to the landscape, yet those delicate blossoms aren't just for show. In essence the flower is the plant's reproductive organ, which manufactures pollen for fertilization and grows tiny seeds, each holding the promise of a new plant.

Male

The male part of the flower is called the stamen. It produces the pollen that is needed to fertilize other flowers. In most flowers the stamen is a thin stalk called a filament that has an enlarged tip called an antler. The antler has little pouches that make the pollen. When the pollen is ripe the pouches break open and release the pollen.

Female

The pistils are the female flower parts that bear seeds. Most flower pistils have a stigma, style and ovary. The stigma is located on the top of the pistil and is sticky to catch the pollen. Once the pollen has been trapped by the stigma it moves down the style, which is a tube leading to the ovary. The ovary contains one or more ovules. Fertilization occurs when the sperm from the pollen unite with an egg cell in the ovule, and a seed grows.

Self Pollination

Most plants do not pollinate themselves, the pollen travels from one flower to another. Yet, there are some plants that self-pollinate and occasionally a non-self-pollinating plant will self-pollinate itself, yet this increases the chances of undesirable characteristics of that plant being carried into future generations. Sometimes plants from these seeds are infertile.

Birds and Insects

Birds and insects are needed to move the pollen from one plant to another. This is the reason for the colorful and fragrant flower petals, or corolla. The petals attract insects and birds to the plants. The birds and insects unwittingly carry the pollen dust from one plant to another, which then lands on the sticky stigma.

Who's Who of Pollination

Bees pollinate more flowers than other insects. They are attracted to the plants by the sweet scent of the flower. Butterflies and moths are attracted to flowers which produce a large amount of nectar. Beetles tend to pollinate white or dull colored flowers, while flies typically pollinate flowers that have flat petals or unpleasant odors. Birds are attracted to petal colors and most scentless red flowers are pollinated by birds.

Seed Within Ovary

When the flower petals fall off they leave behind the ovary which develops into a fruit. The fruit drops from the plant and if the seed within the fruit eventually makes it to fertile soil it can grow into a new plant. An apple, orange or peach is an example of an ovary.