Question

Mention three ways in which pollination can occur

Answer 1

Pollination is a method of sexual reproduction in plants. Pollen grains are transferred from the anther (the male part) to the stigma (the female part). Pollination should happen within the same species for it to work.

Complete answer:
Pollination starts when the pollen grains from the anther of a flower land on the stigma of the same or different flower or plant of the same species. The pollen tube forms inside the style, which connects the stigma and ovary. Once the pollen tube is completely formed, sperm cells are transferred from the pollen grains to the ovary. Later, fertilization takes place.

There are three ways in which the pollen grains can be transferred from the other to the stigma.
The three ways are as follows:
Autogamy – In autogamy, the pollen grains from the anther of a flower may fall on the stigma of the same flower by itself.
Allogamy – In allogamy, the pollen grains from the anther of one flower of a plant falls on the stigma of another flower on another plant of the same species.
Geitonogamy – In geitonogamy, the pollen grains from the anther of one flower falls on the stigma of another flower of the same plant.

Note: There are two types of pollination – cross-pollination and self-pollination. Self-pollination is also known as the primary type, as it includes only a single flower. The pollen grains are transferred from the anther to the stigma of the same flower. In cross-pollination, the pollen grains are transferred from the anther of one flower to the stigma of another flower of the same plant or a different plant of the same species. Self-pollination is autogamy, while cross-pollination can either be allogamy or geitonogamy.