Overview of Mitosis vs. Meiosis

Mitosis

• Starting Condition:

  • A cell with a diploid number of chromosomes (2n).
  • For humans, 2n = 46 chromosomes (23 pairs: 23 from mother, 23 from father).

• Process:

  • The cell undergoes cytokinesis.
  • Results in two cells each having the same genetic information as the original (2n each).
  • Cells can re-enter the cell cycle, growing and replicating DNA, to undergo mitosis again.
  • This process is cyclical and is how most body cells grow and divide.

• Result:

  • Two identical diploid cells.

Meiosis

• Starting Condition:

  • A cell with a diploid number of chromosomes (2n).

• Phases:

  • Meiosis I:
    • DNA replication occurs during interphase.
    • Homologous pairs are separated.
    • Results in two cells with haploid number of chromosomes (n), 23 chromosomes each in humans.
  • Meiosis II:
    • Similar to mitosis but starts with haploid cells.
    • Each cell divides to form four distinct haploid cells.

• Genetic Variation:

  • Cells produced do not have the same genetic information.
  • Random assortment of maternal and paternal chromosomes.

• Result:

  • Four non-identical haploid cells.

Key Differences Between Mitosis and Meiosis

• Mitosis:

  • Cyclical process.
  • Produces two identical diploid cells.
  • Occurs in somatic cells (body cells).

• Meiosis:

  • Not cyclical, leads to the production of gametes.
  • Produces four non-identical haploid cells.
  • Occurs in germ cells (testes in males, ovaries in females).

Functions

• Mitosis:

  • Growth and repair of body tissues.
  • Single cell turns into a multicellular organism.

• Meiosis:

  • Production of gametes for sexual reproduction.
  • Genetic diversity through variation in gametes.