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Sex Cells

What’s the chance of being male or female? Parent’s chromosomes are in pairs. When sex cells are made they only get one chromosome from each pair. So half a man’s sperm cells get an X chromosome and half get a Y chromosome. All a women’s egg cells get an X chromosome. When a sperm cell fertilises an egg cell the chances are 50% that it will be an X or a Y sperm. This means that there is a 50% chance that the baby will be a boy or a girl.


Huntington ’s disease and Pre-natal tests

Huntington’s Symptoms: memory problems, balance, they slur words so people think they


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