Cleavage is a process in which cell is divided into several parts without increasing in size. There are 4 stages of cleavage i. e. 2-cell, 4-cell, 8-cell and 16 cell stages. 2 cell embryo cleavage occurs after 30 hours of fertilization. 4 cell embryo cleavage occurs after 48 hours. 6 cell embryo cleavage occurs on third day of fertilization. 8 cell embryo cleavage occurs on fourth day of fertilization and more than 100 cells are formed.
The best description of the events occurring during Ana-phase I of meiosis:
c. Homologous chromosomes randomly separate and migrate to opposite poles.
Explanation:
Meiosis:
It is such type of cell division that occur in animals, plants resulting in four daughter cells and each of daughter cell have the half number of chromosomes from the parent cell.
Anaphase is one of important phases of meiosis. The option a is incorrect as chromosomes go randomly to opposite poles.
The option b is incorrect as all of chromosomes inherited from mother and father goes randomly to opposite poles.
The option c is correct as it is the true description of anaphase I of meiosis.
The option d is incorrect as the sister chromatids don't separate rather they remain joined.