The fact that the following molecule serves as a substrate for DNA polymerase in place of dTTP proves what issue with regard to DNA replication?
A)DNA polymerase is highly error prone
B)hydrogen bonding to N-3 of thymine is not critical for substrate recognition
C)base stacking is the true driving force for nucleotide placement
D)substrate shape might be as important as hydrogen bonding for DNA polymerase
E)none of the above

Question

The fact that the following molecule serves as a substrate for DNA polymerase in place of dTTP proves what issue with regard to DNA replication? 
A)DNA polymerase is highly error prone 
B)hydrogen bonding to N-3 of thymine is not critical for substrate recognition 
C)base stacking is the true driving force for nucleotide placement 
D)substrate shape might be as important as hydrogen bonding for DNA polymerase 
E)none of the above

Quizplus · Accepted Answer

The fact that a molecule other than dTTP can function as a substrate for DNA polymerase suggests that substrate shape may be as important as hydrogen bonding for the enzyme. This indicates that DNA polymerase's recognition of substrates is not solely based on the presence of specific hydrogen bond donors and acceptors in the nucleotides, but rather a combination of factors including shape and stacking interactions. Option A can be ruled out as it is not stated or suggested that DNA polymerase is highly error prone. Option B is partially correct but not a complete explanation for why the alternative substrate can be used. Option C is not supported by the given information.

The Fact That the Following Molecule Serves as a Substrate