Which genetic mechanism prevent the self-pollination

Answer

**Step-by-Step Solution:**

1. **Understanding Self-Pollination**: Self-pollination occurs when pollen from the male part (stamen) of a flower fertilizes the ovule in the female part (ovary) of the same flower. This can lead to a lack of genetic diversity.

2. **Identifying the Genetic Mechanism**: To prevent self-pollination, certain genetic mechanisms are in place. One of the primary mechanisms is self-incompatibility.

3. **Explaining Self-Incompatibility**: Self-incompatibility is a genetic mechanism that prevents self-fertilization. In plants exhibiting this mechanism, the pollen from the same flower or plant is unable to fertilize its ovules. This can occur due to various genetic factors that lead to the rejection of self-pollen.

4. **Result of Self-Incompatibility**: As a result of self-incompatibility, plants are forced to engage in outbreeding or cross-pollination, which promotes genetic diversity and adaptability in the population.

5. **Conclusion**: The genetic mechanism that prevents self-pollination is self-incompatibility, ensuring that plants can only reproduce with pollen from different individuals.

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