Chapter 12, Problem 47A

Summary Introduction

To analyze: 

The process of gamete formation.

Introduction:

The cell division is of 2 types, mitosis and meiosis. The mitosis is the process of the cell

division, which occur in all the somatic cells present in the body of the multicellular organism.

The meiosis is the cell division, which occurs to produce the haploid cells.

Explanation of Solution

The gametes are haploid in nature, and they formed by the process of meiosis, which result in reductional division. The meiosis is a division divided into two different subdivision cycles. So, the meiotic division takes place as meiosis I and meiosis II. Before the meiosis occurs, the replication of the genetic material takes place, which makes the sister chromatids. In the meiosis I, the replicated chromosomes, are divided into two daughter cells. Each daughter cell after meiosis I have a pair of sister chromatids, which result in the reduction of ploidy from diploid to haploid.

The meiosis II is similar to the mitosis. Hence, the ploidy of the cell in the meiosis II remains unchanged. As a result, the four daughter cells obtained after the complete meiotic division is haploid in nature.  

Conclusion

The meiotic cell division causes a reduction in the number of chromosomes present in the cells, and the daughter cells have single set of chromosomes, resulting in formation of gametes.