What is a mutagen?

A mutagen is defined as a chemical or physical agent that induces mutations in the genetic material of organisms. This means that mutagens can alter the DNA sequence, which can lead to changes in how cells function or develop. These mutations can have various effects, ranging from benign to harmful, depending on the nature of the mutation and where it occurs within the genome. Understanding mutagens is crucial in fields related to genetics, health, and safety, as they can contribute to the development of cancer and other genetic disorders.

The other options describe different substances or agents. While a chemical that accelerates cell growth may influence cell behavior, it does not specifically pertain to changes within genes. Similarly, a substance that triggers allergic reactions relates to immune responses rather than genetic mutations, and a type of virus that causes disease pertains to infectious agents rather than mutagenic activity. Therefore, the identification of mutagens as agents causing mutations is what makes this option the most accurate representation of the term.