Question

In frogs an area Just opposite to the site of entry of sperm into the ovum is known as………………….

Answer 1

Hint: This region is made because of the morphological and physiological changes that happen within the egg because of the entry of the spermatozoon into the egg. it's most vital for the organization of events within the egg.

Complete answer
A grey crescent may be a structure shaped on the alternative facet of spermatozoan entry during a frog egg. It's a bunch of growth factors that essentially regulate, that a part of} the cell becomes that part of the body. When fertilization on the facet opposite of spermatozoan penetration, then an area of the recent fauna of frogs and a few salamanders, that forms simply

Additional information:
The protoplasm at the sting of the ovum, known as the animal tissue protoplasm, rotates thirty degrees towards the location of spermatozoan entry. Rotation exposes a wedge of the protoplasm beneath, generally manufacturing a lucid zone of lighter color known as the grey crescent.
Sperm continually enter the frog egg within the animal hemisphere. Once this happens the animal tissue protoplasm (not all the cytoplasm) rotates toward the location of spermatozoan entry. This creates a band of diffusely pigmented protoplasm, known as the grey crescent, on the alternative facet of spermatozoan entry.

So the correct answer is ‘Gray crescent’.

Note:
The gray crescent establishes the bilateralism of the frog. Even before the primary cleavage event, we {will|we are able to} tell however the frog will develop. The primary cleavage plane continually bisects the grey crescent. the location of spermatozoan entry can become the ventral region of the frog (the belly). The grey crescent can belong to the dorsal region of the frog (the back).