Suppose you are provided with an actively dividing culture of E.coli bacteria to which radioactive thymine has been added. What would happen if a cell replicates once in the presence of this radioactive base?

A) Neither of the two daughter cells would be radioactive

B) One of the daughter cells, but not the other, would have radioactive DNA.

C) All four bases of the DNA would be radioactive.

D) DNA in both daughter cells would be radioactive.

In E.coli, there is a mutation in a gene called dnaB that alters the helicase that normally acts at the origin. Which of the following would you expect as a result of the this mutation?

A) No replication fork will be formed.

B) Additional proofreading will occur.

C) Réplication will occur via RNA polymerase alone.

D) Replication will require a DNA template from another source.

In E.coli, which enzyme catalyzes the elongation of a new DNA strand in the 5' --> 3' direction?

A) helicase

B) primase

C) DNA ligase

D) DNA polymerase III