AP BIOLOGY

Detailed explanation-1: -The chemical or physical agents that cause mutations are called mutagens. Examples of physical mutagens are ultraviolet (UV) and gamma radiation. Radiation exerts its mutagenic effect either directly or by creating free radicals that in turn have mutagenic effects.

Detailed explanation-2: -A mutagen is a chemical or physical agent capable of inducing changes in DNA called mutations. Examples of mutagens include tobacco products, radioactive substances, x-rays, ultraviolet radiation and a wide variety of chemicals.

Detailed explanation-3: -Mutagens cause mutations in three different ways: Some act as base analogs and are mistakenly used as substrates when new DNA is synthesized at the replication fork. Some react directly with DNA, causing structural changes that lead to miscopying of the template strand when the DNA is replicated.