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Genomics explainer: how DNA is passed between generations

Almost all of your cells contain a complete copy of your genetic information – your genome – across 46 chromosomes (23 pairs). 

Sperm and egg cells (known as gametes) are different – they have a total of 23 chromosomes, only one of each pair. When a sperm and egg combine during fertilisation, they form a single cell (zygote) that contains the full set of 46 chromosomes, 23 from each parent. 

This single cell divides many times during a person's growth and development, with each new cell containing a complete copy of the genome. 

How DNA is passed down between generations