Class 12th Biology 2017 Set3 Delhi Board Paper Solution
Question 26
How is polyspermy prevented in humans?
Answer
When a sperm comes in contact with the zona pellucida layer of the ovum, it induces changes in the membrane of the ovum to block the entry of additional sperms. This, thus, prevents the polyspermy and ensures that only one sperm can fertilise an ovum.
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