Meiosis and Fertilisation

• What happens during meiosis?

  1. all of the chromosomes are copied
  2. cell divides into 2
  3. both of these cells divide 1 more time forming gametes
  4. in gametes chromosomes are single =meiosis halved the No of chromosomes
  5. meiosis produces 4 gametes that are genetically different that has different alleles
• What happens to the gametes after meiosis?

  1. in SR the gametes join together= fertilisation
  2. after fertilisation the cell has the normal number of chromosomes
• difference between meiosis and fertilisation?

  meiosis halved the No of chromosomes whilst fertilisation restores the No of chromosomes
• what happens after fertilisation?

  1. new cell produced divides by mitosis producing a clump of identical cells = embryo
  2. as embryo develops, cells differentiate forming different cell types