Quiz 3: DNAReplication_Set1

The 5' → 3' exonuclease activity of E. coli DNA polymerase I is involved in:

removal of RNA primers by nick translation.

The Meselson-Stahl experiment established that:

DNA synthesis in E. coli proceeds by a semiconservative mechanism.

What does processivity of the replicative polymerase mean?

the ability of an enzyme to catalyze many consecutive reactions without releasing its substrate

What is a short section of RNA that is extended by DNA polymerase?

primer

Which statement about enzymes that interact with DNA is TRUE?

Exonucleases degrade DNA at a free end.

During synthesis of a new complementary DNA strand, the parent double helix acts as a(n):

template.

Prokaryotic DNA polymerase III:

has a β subunit that acts as a circular clamp to improve the processivity of DNA synthesis.

What must happen to the strands of DNA in order for replication to occur?

unwinding

The e subunit of E. coli DNA polymerase III acts as a:

3'-to-5' exonuclease and removes mismatched nucleotides from the 3' end of DNA by hydrolysis.

Which best describes the directionality of DNA replication?

5' → 3' direction on both strands