Question

Describe two phenomenons which can prevent both autogamy and geitonogamy and ensure xenogamy in flowering plants.

Answer 1

1) Autogamy- is the transfer of pollen grains from the anther to the stigma of the same flower.

2) Geitonogamy- is the transfer of pollen grains from the anther to the stigma of another flower of the same plant.

• Production of unisexual flowers i.e the male and female parts are present on different plants (dioecious) or on different flowers in the same plant (monoecious).
• Both these methods prevent autogamy and geitonogamy.

3) Xenogamy is the transfer of pollen grains from the anther to the stigma of a different plant.

• It is the type of pollination which brings genetically different types of pollen grains to the stigma and brings genetic variations.