- All human cells have 46 chromosomes, however sperm and egg cells only have 23. This is because, if a sperm and egg cell have to come together to create a fertilized egg, which means 23 + 23, in the end it will create a correct cell of 46 chromosomes.
- The process of meiosis is different to mitosis, where the difference is that meiosis does the process twice.
- The steps of division are; prophase 1, metaphase 1, anaphase 1, telophase 1, prophase 2, metaphase 2, anaphase 2 and telophase 2.
Prophase 1 is when chromosomes are going to pair up with other chromosomes with approximately the same size and same gene location, these chromosomes are called homologous (match up). Then the pairs 'cross over' and transfer genetic information which contributes to the variety of genes and traits in children.
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Telophase 1 is when we are now left with two cells but the process is done again like mitosis.
Prophase 2 - no crossing over and spindle fibers start to form
Metaphase 2 - chromosomes line up in a single file like mitosis
Anaphase 2 - the chromosomes move away.
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