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Question
Define ‘reproductive isolation’ and explain two types of reproductive isolation.
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Solution
Reproductive Isolation: Prevents interbreeding between the populations whether they are geographically isolation or living close together.
Types of Isolating mechanisms :
1. Pre -mating or pre-zygotic isolating mechanisms : In habitat Isolation, members of a population living in the same region occupy different habitat. Thus potential mates do not meet. In seasonal isolation, members of a population attains sexual isolation, members of a population attain sexual maturity at the different times, thus preventing interbreeding.
In ethological isolation, members of two populations have different mating behaviours. This prevents interbreeding.
In mechanical isolation, the members of two populations have differences in the structure of reproductive organs. So interbreeding is not possible.
2. Post-matting or post zygotic isolating mechanisms are : Gamete mortality (Sperms transfer takes place but egg is not fertilized), Zygote mortality (Egg is fertilized but zygote dies) and hybrid sterility (Hybrids are sterile)
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