The transfer of pollen grains from the anther to a sigma is
Answer Details
The transfer of pollen grains from the male part of a flower, called the anther, to the female part of a flower, called the stigma, is called pollination. Pollination is a very important step in the process of sexual reproduction in flowering plants because it allows the male gamete (sperm) to reach the female gamete (egg) for fertilization, which leads to the formation of seeds.
There are two main types of pollination: self-pollination and cross-pollination. Self-pollination occurs when the pollen from the anther of a flower lands on the stigma of the same flower or on another flower on the same plant. Cross-pollination occurs when the pollen from the anther of one flower lands on the stigma of another flower on a different plant of the same species.
Once the pollen grains land on the stigma, they begin to grow a tube called a pollen tube that grows down through the style towards the ovary. This tube contains the male gamete (sperm) that will fertilize the female gamete (egg) to form a seed.
So, to summarize, the transfer of pollen grains from the anther to the stigma is called pollination, which is an important step in the sexual reproduction of flowering plants that allows for the formation of seeds.