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The Nucleus
Figure 5.2 DNA is contained within chromosomes, as is shown here. DNA contains the information necessary for protein synthesis in special regions called genes. Scientists estimate that humans have approximately 35,000 different genes which control all aspects of human life from hair color to predisposition to certain diseases.
associated with chromatin provide a regulatory function by helping determine which genes are active. When a cell is preparing to divide, it duplicates its DNA molecules so each daughter cell will receive all the required hereditary instructions. In addition, prior to cell division,
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