Looking for classes? Ksquare Career Institute, Bengaluru →
What happens during fertilisation in humans after many sperms reach close to the ovum?
A
Cells of corona radiata trap all the sperms except one
B
Only two sperms nearest the ovum penetrate zona pellucida
C
Secretions of acrosome help one sperm enter cytoplasm of ovum through zona pellucida
D
All sperms except the one nearest to the ovum lose their tails
Detailed Solution
Many sperms reach the ovum in the ampullary region, but only one fertilises it.
When a sperm comes in contact with the zona pellucida layer of the ovum, it induces changes in the membrane that block the entry of additional sperms.
The secretions of the acrosome (hydrolytic enzymes) help the sperm to enter the cytoplasm of the ovum through the zona pellucida and the plasma membrane.
The corona radiata does not trap the other sperms, two sperms do not enter, and the other sperms do not lose their tails.
Hence the secretions of the acrosome help one sperm to enter the cytoplasm of the ovum through the zona pellucida.
When a sperm comes in contact with the zona pellucida layer of the ovum, it induces changes in the membrane that block the entry of additional sperms.
The secretions of the acrosome (hydrolytic enzymes) help the sperm to enter the cytoplasm of the ovum through the zona pellucida and the plasma membrane.
The corona radiata does not trap the other sperms, two sperms do not enter, and the other sperms do not lose their tails.
Hence the secretions of the acrosome help one sperm to enter the cytoplasm of the ovum through the zona pellucida.