Question

The term used for transfer of pollen grains from anthers of one plant to stigma of a different plant which, during pollination, brings genetically different types of pollen grains to stigma, is :

• A. Xenogamy
• B. Geitonogamy
• C. Chasmogamy
• D. Cleistogamy

Hint:

Pollination is the process of transferring pollen grains from the anther to the stigma of a pistil.

Answer 1

The Correct Option is A

During Xenogamy, pollen grains from one plant's anthers are transferred to the stigma of another plant, resulting in genetically distinct pollen grains during pollination.

In flowering plants, the male and female gametes are produced in the pollen grain and embryo sac respectively. However, these gametes are non-motile and need to be brought together for the fertilization process.

Complete answer:

The transfer of pollen grains to the pistil's stigma is called pollination. Pollination can be of two types self-pollination and cross-pollination.

In xenogamy, the pollen grains are transferred to the stigma of the different plants. This brings genetically distinct pollen grains to the stigma of the flower.

Thus, option A is the correct answer.

Note: Complete autogamy is uncommon as it needs synchrony of pollen and stigma at the same time. The main difference between Xenogamy and Allogamy is that Xenogamy transfers pollen grain from one flower's anther to the stigma of a genetically different flower of the same species. In allogamy, pollen grains are transferred from the anther of a flower to the stigma of another either in the same plant or a different plant of the same species.

Answer 2

Pollination is the process of transferring pollen grains from the anther to the stigma of a pistil. The several types of pollination are:

• In autogamy, pollination is achieved within the same flower. Some plants like Viola produce 2 types of flowers. 
  • A type of flower that has exposed anthers and stigma is known as chasmogamous. 
  • The type of flower that does not open at all is referred to as a cleistogamous flower.
  • Hence, options C and D are incorrect.
• Geitonogamy is the transfer of pollen grains from the anther of a flower to the stigma of another flower within the same plant. As the pollen grains are from the same plant, they will be genetically similar to the stigma. Hence, option B is incorrect.
• Xenogamy is the transfer of pollen grains from the anther to the stigma of a different plant. It brings together genetically distinct types of pollen grains.

Therefore, the correct answer is A) Xenogamy.