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Viruses reproduce within the living cells of the host and use the cellular machinery to synthesize their own genome and other components. To gain entry into cells, they have developed a variety of mechanisms to introduce their genes and proteins into host cells.
Lower esophageal sphincter! <span />
Hereditary diseases and cancer are ways in which inherited factors can affect a persons health
Mutation causes change in an organisms DNA, resulting in a change in all aspects of the organisms life. It affects how the organism looks, and how it behaves. If there was no mutation, an organism could not change, therefore there wouldn't be evolution at all.
