Question

The type of cleavage in a zygote depends upon

• A. Amount of yolk
• B. Amount of cytoplasm
• C. Size of nucleus
• D. All of the above

Answer 1

The correct option is A Amount of yolk

The amount of yolk in the zygote determines the type of cleavage. Placental mammals have a very small amount of yolk and undergo holoblastic cleavage because the nourishment is provided by the mother's body for the development. Other species, such as birds, with a lot of yolk in the egg to nourish the embryo during development, undergo meroblastic cleavage.

So, the correct answer is option A.