In photoreactivation,DNA damage caused by UV light is reversed by DNA photolyase which
A)is activated by UV light to form a complex.
B)removes nicks in the DNA backbone.
C)forms a complex with thymine dimers and the complex absorbs visible light which reverses the dimerization.
D)binds to the adenine bases opposite the thymine dimer.
E)All of the above.

Question

Quizplus · Accepted Answer

DNA photolyase forms a complex with thymine dimers in the presence of visible light and reverses the dimerization. It does not remove nicks in the DNA backbone or bind to the adenine bases opposite the thymine dimer. Photolyase is not activated by UV light but rather by visible light. Therefore, only choice C is correct.

In Photoreactivation,DNA Damage Caused by UV Light Is Reversed by DNA