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Question
Name any three types of postmating isolating mechanisms.
Solution
- Gamete mortality: Gametes have a limited life span. Due to one or the other reasons, if the union of the two gametes does not occur in the given time, it results in gamete mortality.
- Zygote mortality: Here, the egg is fertilized but the zygote dies due to one or the other reasons.
- Hybrid sterility: Hybrids develop to maturity but become sterile due to failure of proper gametogenesis (meiosis). e.g., Mule is an intergeneric hybrid that is sterile.
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