Fruit has its beginnings in the pollination process. This process is the transfer of pollen from the male to the female part of the flower. The male is referred to as the anther, while the female is called the stigma. This process not only occurs inside the same flower, but the pollen is also spread to neighboring flowers by the wind, animals and a variety of insects. The most common insect to spread pollen is the bee. The bee moves from flower to flower, and pollen is spread to each flower. When a bee, insect or element of nature moves pollen from flower to flower, the process is termed cross-pollination. Sometimes, the pollen stays with the same flower, and the result is self-pollination. Self-pollination happens as a result of the pollen coming into contact with the stigma of the flower.
For two flowers to pollinate, they must be of the same species. Pollen is different in each plant, and has characteristics that make pollen from one plant different from that of another plant. For example, some kinds of pollen have spikes that allow it to better stick to an animal. This is one way in which a flower can adapt its pollen to be more successful in the cross-pollination process.
Development of Fruit
Grains in the pollen erect a tube on the flower that travels all the way down into the female part of the plant. The female part of the plant is at the base of the pistil, which houses the developing pollen tube. The pollen tube will react with a ovule in the female part of the plant to fertilize an egg. The egg and the ovary develop together, and a sheath or protective layer is formed around a seed. The ovary itself becomes the actual fruit produced by the plant. Depending on the number of eggs per ovule, multiple ovaries can become fruits. In some flowers, there is only one seed or one ovule, producing only one fruit at a time. Each fruit contains a protective layer, water, nutrients and a seed. Some fruits will have numerous seeds that can be planted and harvested.