The transfer of pollen male gamete in plants to stigma which contains females gamete is known as pollination. Pollination is essential for fertilization, which is the process of sexual reproduction in plants that leads to the formation of seeds.

There are two types of pollination: self-pollination and cross-pollination.

1. Self-pollination: This occurs when pollen from the anther of a flower is transferred to the stigma of the same flower. Self-pollination is common in plants that have perfect flowers, which contain both male and female reproductive organs.

2. Cross-pollination: This occurs when pollen from the anther of one flower is transferred to the stigma of a different flower. Cross-pollination is facilitated by various agents such as wind, insects, birds, and mammals. Cross-pollination increases genetic diversity and results in healthier and more vigorous offspring.

Once the pollen grains are deposited on the stigma, they germinate and produce a pollen tube. The pollen tube grows through the style, delivering the sperm cells to the ovary, where fertilization takes place.