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Science

Cell division

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Meiosis - higher

Gametes are formed from cells in the reproductive organs by a type of cell division called meiosis.

MaleFemale
reproductive organtestesovaries
gametesspermeggs

The cells that are formed by meiosis have half as many chromosomes as the cell that formed them. Human body cells contain 23 pairs of chromosomes, while human gametes contain 23 single chromosomes.

The main features of meiosis are:

  • the chromosomes are copied
  • the cell divides twice, forming four gametes

The diagram outlines how this works.

chromosomes divide, similar chromosomes pair up, sections of DNA get swapped, pairs of chromosomes divide,  chromosomes divide

Stages of meiosis

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