Question

The formation of chemical bonds between nucleotides on the same strand of DNA resulting from UV light exposure may cause:

A) Thymine dimerization
B) Base excision
C) Nucleotide excision repair
D) Homologous recombination

Answer 1

Exposure to UV light can cause adjacent thymines in DNA to form thymine dimers, disrupting replication and transcription. These dimers are commonly repaired by nucleotide excision repair mechanisms in the cell.

Step-by-step explanation:

The formation of chemical bonds between nucleotides on the same strand of DNA resulting from UV light exposure may cause Thymine dimerization. When UV light is absorbed by DNA, adjacent thymines on a DNA strand can become covalently linked to form a thymine dimer. This dimerization can create significant disruptions in DNA replication and transcription processes. In normal cells, nucleotide excision repair mechanisms identify these abnormal structures, excise the dimers, and replace them with correct nucleotides, preventing the mutation from becoming permanent.