Question

Define pollination. Explain the different types of pollination. List two agents of pollination? How does suitable pollination lead to fertilization?

Answer 1

Pollination:

1. A pollination is a pre-fertilization event or process.
2. The transfer of pollen grain from the anther to the stigma of the flower is called pollination.

Types of pollination:-

1. Self-pollination
2. Cross-Pollination

1.Self-Pollination:

This types of pollination occur when the pollen of one flower transfers to the stigma of the same flower, or another flower of the same plant.

1. Autogamy is a type of self-pollination where the transfer of pollen grains from the anther to the stigma takes place within the same flower.
2. Opening and exposure of another and stigma are necessary for autogamy.
3. There are two conditions for autogamy to takes place:

• Anther-stigma synchronization; when the pollen is released, stigma should be ready to receive it.
• The position of or distance between anther and stigma. Both should be close enough for pollination.

2. Cross-pollination :

This type of pollination occurs when the pollen of one flower transfers to the stigma of another flower of different plants of the same species.

1. Xenogamy is the cross-pollination where the pollen grain transfer occurs across flowers of two different plants. In other words, the transfer of pollen from the anther of one plant to the stigma of another plant.
2. Each type has its own merits, xenogamy, leads to a new variety whereas autogamy helps to preserve parental characters. Plants have various adaptations to accomplish this task.

Agents of pollination:

1. Pollination is done either by biotic agents like insects, birds, and bats or by abiotic agents like wind and water.
2. Pollination is the transfer of male gametes onto the female gametes, while fertilization is the fusion of these two gametes.

Pollination leads to fertilization:

It is the process in which the nuclei of the female gamete and male gamete unite together in the ovary of the flower to form a diploid zygote.