Cells, germ

Cells, germ
The eggs and sperm are the germ cells: the reproductive cells. Each mature germ cell is haploid in that it has a single set of 23 chromosomes containing half the usual amount of DNA and half the usual number of genes. Except for the eggs and sperm, each cell in the human body — there are 100 trillion cells in each of us — contains the entire human genome, all the genetic information necessary to build a human being, and this information is encoded within the cell nucleus in 6 billion base pairs, subunits of DNA, packaged in 23 pairs of chromosomes, one chromosome in each pair coming from each parent. The germs cells — the eggs and sperm — are thus notable exceptions to the usual rules governing chromosomes, genes, and DNA.

Medical dictionary. 2011.

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