Question

What could happen if bacterial DNA is damaged by UV light and the damaged DNA is not repaired by the bacteria?

a.DNA replication can proceed as normal, but transcription is prevented
b. neither DNA replication nor transcription can occur, and the bacteria will probably die
c.transcription can proceed as normal, but replication is prevented
d. the damaged part will be excised and allow DNA replication to proceed

Answer 1

b. neither DNA replication nor transcription can occur, and the bacteria will probably die

Explanation:

Ultraviolet light (UV) is a powerful mutagenic agent that produces thymine dimers among contiguous base pairs. These dimers are highly stable, and thus DNA repair mechanisms are inefficient. UV light is particularly harmful to bacteria and viruses. It is for that reason that UV is used to sanitize by damaging such pathogens, avoiding them from multiplying and consequently also inhibiting transcription.