meiosis and fertilisation

• What process produces gametes in humans?

  Meiosis
• How many pairs of chromosomes are in a normal human cell?

  23 pairs
• What type of chromosomes do gametes contain?

  Single chromosomes
• How many single chromosomes does a human gamete contain?

  23 single chromosomes
• Where does meiosis occur in humans?

  In reproductive organs
• What are the male and female reproductive organs called?

  Testes and ovaries
• What happens to chromosomes in the first stage of meiosis?

  All chromosomes are copied
• How many gametes are produced from one original cell in meiosis?

  Four gametes
• Are the gametes produced by meiosis genetically identical?

  No, they are genetically different
• What is the term for the joining of male and female gametes?

  Fertilization
• What happens to the number of chromosomes after fertilization?

  It is restored to normal
• What type of cell results from fertilization?

  A fertilized egg
• What process occurs after fertilization?

  Cell division by mitosis
• What is formed as the embryo develops?

  Differentiated cell types
• What types of cells can differentiate in animals?

  Nerve cells and muscle cells
• What is the relationship between meiosis and fertilization?

  • Meiosis halves the number of chromosomes
  • Fertilization restores the full number of chromosomes
• What are the stages of meiosis relevant to the AQ8 specification?

  • Meiosis occurs in reproductive organs
  • Chromosomes are copied
  • Cell divides into two
  • Each cell divides again
  • Four gametes are produced
• What is the significance of gametes in sexual reproduction?

  • Gametes are necessary for fertilization
  • They ensure genetic diversity