Which statement about somatic mutations is true?

Which statement about somatic mutations is true?

• A. They occur in non-reproductive cells and are not inherited.
• B. They are inherited by offspring.
• C. They always occur in germ cells.
• D. They never affect phenotype.

Answer: (A)

Somatic mutations are changes in the DNA that occur in body (non-reproductive) cells after fertilization. Because they are not in the germline (sperm or egg), these mutations are not passed on to offspring. That’s why the true statement is that they occur in non-reproductive cells and are not inherited. These mutations can arise in any somatic cell during life and can affect the phenotype of the individual—for example, by altering how a cell grows or functions, which is a common route to cancer. They do not have to occur in germ cells, which is why they’re not inherited. In contrast, germline mutations in reproductive cells can be transmitted to the next generation, and some somatic mutations can be present without affecting the germline at all, so they aren’t inherited.

Somatic mutations are changes in the DNA that occur in body (non-reproductive) cells after fertilization. Because they are not in the germline (sperm or egg), these mutations are not passed on to offspring. That’s why the true statement is that they occur in non-reproductive cells and are not inherited.

These mutations can arise in any somatic cell during life and can affect the phenotype of the individual—for example, by altering how a cell grows or functions, which is a common route to cancer. They do not have to occur in germ cells, which is why they’re not inherited. In contrast, germline mutations in reproductive cells can be transmitted to the next generation, and some somatic mutations can be present without affecting the germline at all, so they aren’t inherited.