A molecule of bacterial DNA introduced into a yeast cell is imported into the nucleus but fails to replicate with the yeast DNA. Where do you think the block to replication arises? Choose the protein or protein complex below that is most probably responsible for the failure to replicate bacterial DNA. Give an explanation for your answer.

A molecule of bacterial DNA introduced into a yeast cell is imported into the nucleus but fails to replicate with the yeast DNA. Where do you think the block to replication arises? Choose the protein or protein complex below that is most probably responsible for the failure to replicate bacterial DNA. Give an explanation for your answer.

(a) primase
(b) helicase
(c) DNA polymerase
(d) initiator proteins

Answer: 

You have discovered an "Exo-" mutant form of DNA polymerase in which the 3'-to-5' exonuclease function has been destroyed but the ability to join nucleotides together is unchanged. Which of the following properties do you expect the mutant polymerase to have?

You have discovered an "Exo-" mutant form of DNA polymerase in which the 3'-to-5' exonuclease function has been destroyed but the ability to join nucleotides together is unchanged. Which of the following properties do you expect the mutant polymerase to have?

(a) It will polymerize in both the 5'-to-3' direction and the 3'-to-5' direction.
(b) It will polymerize more slowly than the normal Exo+ polymerase.
(c) It will fall off the template more frequently than the normal Exo+ polymerase.
(d) It will be more likely to generate mismatched base pairs.

Answer: 

Which of the following statements about the newly synthesized strand of a human chromosome is true?

Which of the following statements about the newly synthesized strand of a human chromosome is true?

(a) It was synthesized from a single origin solely by continuous DNA synthesis.
(b) It was synthesized from a single origin by a mixture of continuous and discontinuous DNA synthesis.
(c) It was synthesized from multiple origins solely by discontinuous DNA synthesis.
(d) It was synthesized from multiple origins by a mixture of continuous and discontinuous DNA synthesis.

Answer: 

What part of the DNA replication process would be most directly affected if a strain of bacteria lacking DNA ligase were used to make the cell extracts?

What part of the DNA replication process would be most directly affected if a strain of bacteria lacking DNA ligase were used to make the cell extracts?

(a) initiation of DNA synthesis
(b) Okazaki fragment synthesis
(c) leading-strand elongation
(d) lagging-strand completion

Answer: 

What part of the DNA replication process would be most directly affected if a strain of bacteria lacking single-strand binding protein were used to make the cell extracts?

What part of the DNA replication process would be most directly affected if a strain of bacteria lacking single-strand binding protein were used to make the cell extracts?

(a) initiation of DNA synthesis
(b) Okazaki fragment synthesis
(c) leading-strand elongation
(d) lagging-strand completion

Answer: 

What part of the DNA replication process would be most directly affected if a strain of bacteria lacking helicase were used to make the cell extracts?

What part of the DNA replication process would be most directly affected if a strain of bacteria lacking helicase were used to make the cell extracts?

(a) initiation of DNA synthesis
(b) Okazaki fragment synthesis
(c) leading-strand elongation
(d) lagging-strand completion

Answer: 

What part of the DNA replication process would be most directly affected if a strain of bacteria lacking the exonuclease activity of DNA polymerase were used to make the cell extracts?

What part of the DNA replication process would be most directly affected if a strain of bacteria lacking the exonuclease activity of DNA polymerase were used to make the cell extracts?

(a) initiation of DNA synthesis
(b) Okazaki fragment synthesis
(c) leading-strand elongation
(d) lagging-strand completion

Answer: