The inherited instructions, contained in genes, that specify the activities of cells and thereby the development and functioning of the whole body. Each gene in a chromosome contains the coded instructions for a cell to make a particular protein, which may have a specific structural or catalytic function in the body. The DNA that makes up genes consists of 2 long intertwined strands, each consisting of a sequence of 4 different chemicals called nucleotide bases. These 4 bases are adenine, thymine, cytosine, and guanine (often abbreviated to A, T, C, and G). The sequence of these bases along the DNA strands makes up the genetic code.
Genetic code |
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