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DNA and cell division

Gametes and fertilisation


Cells in the reproductive organs (testestestes: An organ that produces the male reproductive cells. and ovariesovaries: A pair of organs in the female reproductive system where ova (eggs) and sex hormones are produced. in humans) divide to form gametes. Gametes are sex cells:

  • Male gametes are sperm (produced in the testes)
  • Female gametes are eggs (produced in the ovaries)

Gametes contain one set of genetic information, while body cells contain two sets of genetic information. The type of cell division that produces gametes is called meiosis.


Fertilisation is the joining or fusion of a male gamete and a female gamete. When fertilisation happens, a single body cell with new pairs of chromosomeschromosome: One of the rod shaped bodies found in the nucleus of cells that contain genetic information (DNA). is formed. The new cell then divides over and over again by mitosismitosis: A type of cell division which produces daughter cells identical to the parent.. This creates the many cells that eventually form a new individual.

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