The Reduction in the Number of Chromosomes to Half the Normal

Question

The reduction in the number of chromosomes to half the normal count occurs during:
A)meiosis.
B)crossing over.
C)mitosis.
D)fertilization.

Accepted Answer

The reduction in the number of chromosomes to half the normal count is a key event in the formation of gametes, and it occurs during meiosis. Meiosis is a specialized type of cell division that produces four daughter cells, each containing half the number of chromosomes as the parent cell. This is essential for sexual reproduction, as it allows the fusion of two gametes during fertilization to restore the full complement of chromosomes in the zygote. Crossing over occurs during meiosis and contributes to genetic diversity, but it is not directly involved in chromosome number reduction. Mitosis is a type of cell division that produces two daughter cells with the same number of chromosomes as the parent cell. Fertilization is the process by which gametes fuse, but it does not involve chromosome number reduction.