Question

Define pollination. Briefly describe different kinds of pollination in flowering plants.

Hint:

Pollination = transfer of pollen to stigma. Self-pollination maintains purity; cross-pollination promotes variability.

Answer 1

Definition: Pollination is the transfer of pollen grains from the anther of a flower to the stigma of the same or another flower for fertilization. 

Types of Pollination: \[\begin{array}{rl} 1. & \text{Self-Pollination (Autogamy): - Pollen grains from the anther are deposited on the stigma of the same flower. - Example: pea, wheat. - Ensures purity of species but reduces variation.} \\ 2. & \text{Cross-Pollination (Allogamy): - Pollen grains are transferred from the anther of one flower to the stigma of another flower of the same species. - Example: maize, sunflower. - Promotes genetic variation and adaptability.} \\ 3. & \text{Geitonogamy: - Pollen grains from the anther of one flower are deposited on the stigma of another flower on the same plant. - Genetically similar to self-pollination but requires pollinating agents.} \\ \end{array}\]

Agents of Cross-Pollination: 

- Abiotic: Wind (anemophily), Water (hydrophily). 

- Biotic: Insects (entomophily), Birds (ornithophily), Bats (chiropterophily). 

Conclusion: Pollination is essential for sexual reproduction in flowering plants. Self-pollination ensures stability, while cross-pollination brings genetic diversity.