1. Purpose:
- Mitosis: The primary purpose of mitosis is to enable the growth, development, and repair of somatic (body) cells. It produces two identical daughter cells that are genetically identical to the parent cell.
- Meiosis: Meiosis, on the other hand, is specifically dedicated to the production of gametes (sex cells), such as eggs and sperm, for sexual reproduction. It ensures genetic diversity by reducing the chromosome number by half.
2. Number of Divisions:
- Mitosis: Mitosis involves one division of the cell nucleus, resulting in two daughter cells.
- Meiosis: Meiosis consists of two consecutive divisions of the cell nucleus, resulting in the production of four daughter cells.
3. Chromosome Number:
- Mitosis: The daughter cells produced in mitosis have the same number of chromosomes as the parent cell. They are diploid cells, containing the full complement of chromosomes (46 in humans).
- Meiosis: The daughter cells produced in meiosis have half the number of chromosomes as the parent cell. They are haploid cells, containing half the chromosome complement (23 in humans).
4. Genetic Variation:
- Mitosis: Mitosis produces genetically identical daughter cells since the genetic material is replicated and equally divided between the two cells. There is no exchange or recombination of genetic material.
- Meiosis: Meiosis generates genetic variation through processes such as crossing over and independent assortment. Homologous chromosomes exchange genetic material during crossing over, and during independent assortment, chromosomes align randomly, leading to different combinations of alleles in the daughter cells.
5. Occurrence:
- Mitosis: Mitosis occurs in various tissues throughout the body for growth, development, and tissue repair. It is a continuous process in the body's somatic cells.
- Meiosis: Meiosis occurs only in specialized cells called germ cells (found in the testes and ovaries in humans) and is specifically involved in the formation of gametes for sexual reproduction.
6. Stages:
- Mitosis: Mitosis consists of four stages: prophase, metaphase, anaphase, and telophase, followed by cytokinesis (division of the cytoplasm).
- Meiosis: Meiosis comprises two rounds of division: meiosis I (prophase I, metaphase I, anaphase I, and telophase I) and meiosis II (prophase II, metaphase II, anaphase II, and telophase II), followed by cytokinesis after each division.
In summary, mitosis is involved in growth and tissue repair, produces identical diploid daughter cells, and occurs in somatic cells. Meiosis, on the other hand, is specific to sexual reproduction, produces genetically diverse haploid gametes, and involves two rounds of division.
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