Question

What are the types of cleavage?

Answer 1

Cleavage:

1. A sequence of mitotic divisions in which the huge volume of egg cytoplasm gets divided into several smaller, nucleated cells is known as cleavage.
2. Cleavage is the process by which a multicellular creature develops.
3. The rapid mitotic division takes place during embryological development.
4. The zygote undergoes rapid mitotic divisions and the single zygote into the multicellular structure is called a blastocyst.

Types of cleavage:

Determinate cleavage:

1. Determinate cleavage is also called Mosaic cleavage.
2. This type of cleavage mostly takes place in annelids, arthropods, and molluscs.
3. The blastomere produced by the early development of an embryo can't develop into a fully developed embryo.

Indeterminate cleavage:

1. Indeterminate cleavage is also called regulative cleavage.
2. This type of cleavage takes place in invertebrates.
3. In this cleavage, the original cell in the embryo divides into two cells which on separation can develop into a whole organism.

Meroblastic cleavage:

1. This type of cleavage takes place in the zygote which contains a large concentration of yolk.
2. The zygote due to the presence of yolk undergoes partial cleavage.

Holoblastic cleavage:

1. This type of cleavage takes place in which the concentration of yolk is not very large( iso lethal cell).
2. The zygote completely divides into blastomeres at each cleavage and the number of blastomeres goes on increasing.