Question

The major event that occurs during the anaphase of mitosis, which about the equal distribution of chromosome is
A.Replication of the genetic material
B.Splitting of the chromatids
C.Splitting of the centromeres
D.Condensation of the chromates

Answer 1

Hint: Mitosis is the division of a parent cell into two identical daughter cells, each with a nucleus having the same amount of DNA, the same number and kind of chromosomes and the same hereditary instructions as the parent cell. Hence, it is also known as the equational division.

Complete answer:
Anaphase comprises of the following events :
-The sister chromatids of each chromosome separate from their respective mates and begin to move toward the opposite poles.
-The separation of the chromatids starts at the kinetochores and the arms trail behind.
-With the result the chromosomes are pulled into V,L,J and I shapes depending upon the position of the kinetochores.
-As the chromatids move apart, the polar fibres of the spindle elongate and the cell becomes longer.
-The anaphase ends when all the chromatids reach the opposite poles. The chromatids are now referred to as chromosomes because they are no longer held to their duplicates.

So, the correct answer is option C.Splitting of centromeres

Additional information:
-It is physically easier for a short, compact chromosome to move through the cytoplasm than -it is for a very long, twisted interphase chromosome.
-The interphase chromosome must be uncoiled and extended for proper error free replication of DNA double strands.
-In their extended form during interphase, the chromosomes are involved in controlling the synthesis of all materials in the cell, but during cell division this function ceases.

Note:
Anaphase is very short and simple. It lasts for only 2-3 minutes. Functional significance of shortening of chromosomes, that occurs in prophase, becomes clear in anaphase.