Side-by-Side Comparison: Mitosis vs. Meiosis

Jul 4, 2024

Side-by-Side Comparison: Mitosis vs. Meiosis

Overview

  • Processes: Both involved in cell division.
  • Cytokinesis: Follows both to split the cytoplasm.
  • Outcomes:
    • Mitosis: Body cells (diploid - 2n).
    • Meiosis: Gametes (sperm and egg cells - haploid - n).

Starting Cell

  • Type: Diploid (2n)
  • Chromosomes: 46 in humans (23 from each parent).
  • Interphase: Chromosome duplication occurs (not part of mitosis/meiosis).

Phases of Mitosis

  1. Prophase:
    • Chromosomes condense (visible and thickening).
  2. Metaphase:
    • Chromosomes align in the middle in a single file.
  3. Anaphase:
    • Chromatids are pulled away to opposite sides.
  4. Telophase:
    • Chromatids are at opposite ends, new nuclei form around them.
  5. Cytokinesis:
    • Cytoplasm splits, resulting in two diploid cells.

Phases of Meiosis

Meiosis I

  1. Prophase I:
    • Chromosomes condense and pair with homologous chromosomes (crossing over occurs).
  2. Metaphase I:
    • Homologous chromosomes align in the middle in pairs.
  3. Anaphase I:
    • Homologous chromosomes are pulled apart to opposite sides.
  4. Telophase I:
    • Chromosomes reach opposite ends, new nuclei form.
  5. Cytokinesis:
    • Cytoplasm splits, resulting in two haploid cells.

Meiosis II

  1. Prophase II:
    • Chromosomes condense (no homologous pairing or crossing over).
  2. Metaphase II:
    • Chromosomes align in the middle in a single file.
  3. Anaphase II:
    • Chromatids are pulled away to opposite sides.
  4. Telophase II:
    • Chromatids reach opposite ends, new nuclei form.
  5. Cytokinesis:
    • Cytoplasm splits, resulting in four non-identical haploid cells.

Key Differences

  • Mitosis:
    • Single division.
    • Produces 2 diploid cells.
    • Identical cells for growth or repair.
  • Meiosis:
    • Two divisions (Meiosis I & II).
    • Produces 4 haploid cells (gametes).
    • Genetic diversity through crossing over and independent assortment.

Fun Facts

  • Simplified illustration with 6 chromosomes for easier understanding (some insects, like mosquitoes, have 6 chromosomes).
  • Sperm and egg combine to form a diploid zygote, which grows via mitosis.

Stay curious! - Amoeba Sisters