Question

Why are both mitosis and meiosis necessary for the normal human life cycle?

Answer 1

Cell division

1. There are two types of cell division- mitosis and meiosis.
2. It is needed for growth, repair, replacement, and reproduction in living organisms.

Mitosis

1. Mitosis is a process that occurs in all cells in the body except reproductive cells.
2. The equational division is another name for mitosis.
3. Mitosis results in the formation of two daughter cells.
4. Prophase, metaphase, anaphase, and telophase are the four stages of mitosis.
5. In mitotic cell division, the number of chromosomes in the daughter cells remains the same (i.e., diploid 2n).

Significance of mitosis in the human life cycle

1. Mitosis guarantees that the two daughter cells inherit the same number of chromosomes as the parent cell and share the same characteristics.
2. It is responsible for growth, development, and repair in humans.
3. It ensures metabolic continuity by conveying identical genetic information to daughter cells as is encoded in the parent cell's DNA.

Meiosis

1. Meiosis is a process that occurs in the cells of reproductive organs.
2. The process of meiosis produces four daughter cells.
3. Reduction division is another name for meiosis.
4. As a result of meiosis, the chromosome number is reduced to half in the daughter cells.
5. Meiosis produces gametes (sperm and ova).
6. Meiosis is a two-step process that involves two nuclear divisions: meiosis I and meiosis II.

Significance of meiosis in the human life cycle

1. Crossing over takes place in meiosis, as a result, daughter cells are not identical to the parent cell.
2. Meiosis restores the number of chromosomes in the progeny that is distinctive of the species.
3. It prevents the multiplication of chromosomes, ensuring the human species' stability.