Distribution of visible materials in the egg and in the embryo during cleavage is, however, not always of crucial importance for the localization of parts in the developing embryo. Some substances and cellular inclusions may be displaced without disturbing the normal segregation of the embryo into its subordinate parts. This displacement can most conveniently be accomplished by centrifugation of the [...]
In this article we will discuss about:- 1. Definition of Cleavage 2. Chemical Changes during Cleavage 3. Patterns 4. Nuclei of Cleavage Cells 5. Morula and Blastula. Definition of Cleavage: One of the peculiarities of sexual reproduction in animals is that the complex multicellular body of the offspring originates from a single cell—the fertilized egg. It is necessary, therefore, that [...]
In this article we will discuss about the process of maturation of eggs in the female gamete. After the oocyte completes its growth, it is ready for the reduction divisions. By this time, the chromosomes of the oocyte have reached the stage of diakinesis. The meiotic division in the female gametes cannot, however, proceed in the same way as in [...]