How does a mutagen induce mutation? Explain with example.

Explanation

Mutagens may be physical, i.e., inoising radiation X-ray, UV rays, DNAreactive chemicals, i.e., hydroxyl radicals, `H_(2)O_(2),` etc., or biological such as virus. A jmutagen can induce mutation by inducing, a change in the base sequence by insertion, deletion or substitution.
e.g., a single base sequence substitution at the sixth codon of the `beta`-globin chain of the haemoglobin molecule.
The mutant haemoglobin molecule undergoes polymerisation under low oxygen tension causing the change in the shape of the RBC from biconcave disc to the elongated sickle, i.e., like structure which is not functional.