Living organisms need cell division in order to grow and reproduce. Mitosis and meiosis are two types of cell division. Mitosis occurs in vegetation cells, while meiosis occurs in reproductive cells of animals. In mitosis, a parent cell divides into two identical daughter cells that are the same as the parent cell. Meiosis produces four daughter cells that contain half of the genetic information of the parent cell. Because meiosis produces cells with only one half the genetic information as the parent cell, it’s known as reduction division.
• When would an organism need to undergo the process of mitosis? Meiosis?
An organism needs to undergo mitosis when it needs to grow or repair damaged cells. Mitosis is an asexual form of reproduction that does not require genetic information from two parents. Meiosis is needed to produce gametes in the reproductive organs.
Meiosis occurs when an organism needs to reproduce and requires genetic information from two different parents. It is required for sexual reproduction. Meiosis increases the number of cells by division, and also reduces the genetic information by one half.
• What would happen if meiosis did not occur?
Meiosis reduces the number of chromosomes in a cell by one half. When fertilization occurs, the number of chromosomes is reestablished with genetic information. Meiosis allows for genetic variation in offspring by combining different combinations of genes in gametes. If meiosis did not occur, then chromosomes would be doubled when gametes are fused. Sometimes meiosis does not properly occur, causing an egg or sperm to have the incorrect number of chromosomes. This is known as an abnormality. When an abnormal egg is fertilized, or when a normal egg is fertilized with abnormal sperm, a fetus will have the incorrect number of chromosomes.