What is mutation? why are mutations more serious when they occur in a sex cell?

A mutation is the changing of the structure of a gene, resulting in a variant form that may be transmitted to subsequent generations, caused by the alteration of single base units in DNA, or the deletion, insertion, or rearrangement of larger sections of genes or chromosomes. Mutations in sex cells are more serious because they are heritable and affect the next generation.

Explanation:

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