In the Unit of Heredity, we studied the basic unit of life—cells. We explored the relationship between traits and heredity. We learned how characteristics are passed from one generation to another, how living things are classified based on their characteristics, and how these characteristics help living things survive.
How do our genes pass from our parents? Mitosis and Meiosis are the two ways of reproducing cells. They are cell divisions that can happen in humans and most other animals. A cell produces two clones of itself, each with the same number of chromosomes when it divides by way of mitosis; A cell produces four cells, called gametes ( sperm in males and eggs in females) when it divides by way of meiosis.
During Mitosis, it makes more diploid cells. It works by copying each chromosome and then separating the copies to different sides of the cell. In result, when the cell divides down the middle, each new cell gets its own copy of each chromosome. In summary, chromosomes are copied once, and then the nucleus divides once.
In the figure below shows the phases of mitosis.
During meiosis, it makes haploid gametes. It is a reductive type of cell division which results in cells with fewer chromosomes. For example, your father has 23 chromosomes, your mother has 23 chromosomes, then the sperm and egg cells join and forms a cell with 46 chromosomes. It copies with half the usual number of chromosomes. Also, sex cells are made in this process. In summary, chromosomes are copied once, and then the nucleus divides twice.
In the figure below shows the phases of meiosis.
