What is meant by an epigenetic change?
Answer and explanation
Correct answer: C. A heritable change in gene expression caused by chemical marks such as DNA methylation
- Step 1: Epigenetic marks, such as methyl groups on DNA or modified histones, alter how tightly DNA is packed.
- Step 2: That changes which genes are expressed without changing the base sequence, and some marks can be passed on.
Answer
chemical marks change expression, not the sequence.
Why not the others: A change in the base sequence is a mutation; a chromosome-number error is nondisjunction; epigenetic marks can be inherited in some cases.
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