Question

What is the importance of :
(a) Mitosis
(b) Meiosis

Answer 1

Hint: Cell division happens when one parent cell divides to give rise to two or more daughter cells. It occurs in all living organisms. In eukaryotes, cell division is of two major types- Mitosis and Meiosis. Mitotic cell division is a simple division where two genetically identical daughter cells are formed from the parent cell. In meiotic cell division, a single cell divides twice to form four haploid daughter cells. These daughter cells are called gametes.

Complete answer:
(a) Mitosis: Mitosis is a type of cell division, during which one parent cell produces two genetically identical daughter cells. Mitotic division is essential for the growth of cells. It helps in the development of an organism and replacement of damaged tissues. Mitosis also helps in maintaining purity of the genome as no recombination takes place during the division. In most prokaryotes, mitosis is the process of asexual reproduction.
(b) Meiosis: In meiosis four haploid daughter cells are formed from a single parent cell. These cells are called the gametes (sperms in males and eggs in females). Meiotic cell division is important as it is responsible for the formation of sex cells or gametes required for sexual reproduction. Meiosis constantly maintains the number of chromosomes by halving the same. Due to crossing over, the cells are able to produce new combinations of traits and variations. This is possible only because of meiosis.

Note:
There are several stages within both mitosis and meiosis. In mitosis the division happens through four stages namely prophase, metaphase, anaphase and telophase. During each stage, a distinct characteristic of cell division is observed. For example, chromosomal condensation happens in prophase. Meiosis also occurs through two stages namely meiosis I and meiosis II. In meiosis I, two daughter cells are produced. At the end of meiosis II four daughter cells are produced. Chromosomes are halved during each stage.