The Structure of Cells

The human body has trillions of cells, each one with a nucleus, its command center. In each nucleus, DNA is tightly coiled around proteins called histones that work as support structures for genes

The Role of DNA and Genes
Genes contain the codes for cells to produce the various proteins that organisms need to function. Humans have approximately 25,000 genes. Darwin and his followers taught us that it takes many generations to rewrite this basic genetic code

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