Question
Biology Question on Human Reproduction
Grey crescent is the area
A
at the point of entry of sperm into ovum
B
just opposite to the site of entry of sperm into ovum
C
at the animal pole
D
at the vegetal pole
Answer
just opposite to the site of entry of sperm into ovum
Explanation
Solution
The gray crescent is a structural feature that emerges on the side of a frog egg opposite to where the sperm enters. This region contains a cluster of growth factors that essentially control the determination of specific body parts during development. It represents a cortical area in newly fertilized frog eggs, as well as in certain salamanders, forming shortly after fertilization on the side opposite to where the sperm penetrates.
So, the correct option is (B): just opposite to the site of entry of sperm into ovum