Question

Ultraviolet (UV) radiation is mutagenic

Identify two DNA repair mechanisms that remove UV induced DNA lesions Choose all that apply.
a) photoreactivation
b) synthesis-dependent strand annealing
c) nucleotide excision
d) nonhomologous end joining

Answer 1

Two DNA repair mechanisms that remove UV induced DNA lesions are photoreactivation and nucleotide excision repair.

Step-by-step explanation:

Two DNA repair mechanisms that remove UV induced DNA lesions are photoreactivation and nucleotide excision repair.

Photoreactivation is a direct reversal mechanism specific to the types of damage caused by UV radiation. It involves the action of the enzyme photolyase, which is activated by visible light and can reverse the formation of thymine dimers.

Nucleotide excision repair is another mechanism that can remove UV-induced DNA lesions. It involves the recognition of distortions in DNA caused by thymine dimers and the replacement of the damaged DNA strand with the correct bases.