AP2-BIO

• Meiosis


  The process by which gametes (sperm and egg cells) are produced, with half the normal number of chromosomes
• Normal human cells


  • Contain 23 pairs of chromosomes
• Gametes (sperm and egg cells)

  • Contain 23 single chromosomes
• Meiosis

  1. Chromosomes are copied

  2. Cell divides into two

  3. Both cells divide one more time forming gametes
• Meiosis produces four gametes from one original cell, and each gamete is genetically different
• Fertilization

  The joining of a male gamete (sperm) and a female gamete (egg) to form a new cell with the full number of chromosomes
• Meiosis

  Halves the number of chromosomes
• Fertilization

  Restores the full number of chromosomes
• Embryo

  The clump of identical cells that forms after fertilization, which then differentiates into different cell types
• Mitosis


  Cell division where one cell is copied into two identical cells
• Gametes


  Cells where the chromosomes are not paired, e.g. sperm and egg cells
• Meiosis


  Cell division that produces non-identical gametes
• Meiosis takes place in flowering plants to produce pollen and egg cells
• Sexual reproduction


  Involves the fusion of male and female gametes, mixing genetic information
• Sexual reproduction results in variation in the offspring
• Asexual reproduction


  Involves only one parent, no mixing of genetic information, produces genetically identical offspring (clones)
• Asexual reproduction does not involve gametes or meiosis, only mitosis
• Asexual reproduction in plants


  • Forming tiny buds that drop off and grow into new plants