Question 1

Which of the following best describes the source of energy that drives the synthesis of nucleic acids during DNA replication?

Accepted Answer

Hydrolysis of phosphoanhydride bonds in dNTPs

Question 2

During DNA replication, which enzyme is responsible for unwinding the DNA double helix, and what is the energy source for this process?

Accepted Answer

Helicase; energy from ATP hydrolysis

Question 3

A DNA strand is being synthesized by DNA polymerase. How many ATP equivalents are hydrolyzed to add 10 nucleotides to the growing DNA strand?

Accepted Answer

$$20$$

Question 4

Which of the following sequences is most likely to be found at an origin of replication in eukaryotic DNA?

Accepted Answer

...ATA TTA ATC TTA...

Question 5

Why is the lagging strand synthesized discontinuously during DNA replication?

Accepted Answer

DNA polymerase can only synthesize in the $$5' \rightarrow 3'$$ direction, so the lagging strand is made in short Okazaki fragments

Question 6

Which protein increases the processivity of DNA polymerase, allowing it to add thousands of nucleotides without dissociating from the template?

Accepted Answer

DNA clamp

Question 7

What is the function of telomerase in eukaryotic cells?

Accepted Answer

It extends the ends of linear chromosomes by adding repetitive DNA sequences

Question 8

Which of the following is a correct statement about the mRNA produced during transcription?

Accepted Answer

It is complementary to the DNA template (antisense) strand and identical (except for U/T) to the coding (sense) strand

Question 9

Given the DNA template strand 5' TTT CAG GTG CAT 3', what is the sequence of the mRNA transcribed from this template?

Accepted Answer

5' UUU CAG GUG CAU 3'

Question 10

Which of the following is NOT a similarity between DNA polymerase and RNA polymerase?

Accepted Answer

Template becomes part of the product

Question 11

How many ATP equivalents are hydrolyzed to add 10 nucleotides to an RNA strand during transcription?

Accepted Answer

$$20$$

Question 12

Which of the following sequences is translated into protein?

Accepted Answer

Exon

Question 13

What is the role of single-stranded binding proteins during DNA replication?

Accepted Answer

They prevent reannealing of the separated DNA strands

Question 14

Which step(s) of DNA replication use phosphoanhydride hydrolysis for energy?

Accepted Answer

Initiation, elongation, and termination

Question 15

A mutation prevents the removal of RNA primers during DNA replication. Which enzyme is most likely defective?

Accepted Answer

Endonuclease

Question 16

Which of the following modifications occurs to eukaryotic mRNA before it is translated?

Accepted Answer

Addition of a 5' cap and 3' poly-A tail, and splicing to remove introns

Question 17

Which of the following best explains why origins of replication and promoters are often rich in A-T base pairs?

Accepted Answer

A-T base pairs have weaker interactions than G-C base pairs, making the DNA easier to separate

Question 18

Which of the following statements about telomerase is correct?

Accepted Answer

It is an RNA-dependent enzyme that extends telomeres at the ends of linear chromosomes

Question 19

Which of the following is a function of topoisomerase during DNA replication?

Accepted Answer

It removes strain from overwound DNA ahead of the replication fork

Nucleic Acid Synthesis: Replication and Transcription (GOB Chemistry Study Guide)

Study Guide - Practice Questions