Question 1

Which experiment provided evidence that DNA, and not protein, is the hereditary material in cells?

Accepted Answer

Hershey-Chase experiment

Question 2

During DNA replication, which enzyme is responsible for unwinding the double helix?

Accepted Answer

Helicase

Question 3

The Meselson-Stahl experiment supported which model of DNA replication?

Accepted Answer

Semiconservative replication

Question 4

What is the function of telomerase in eukaryotic cells?

Accepted Answer

It extends the ends of linear chromosomes to prevent shortening during replication.

Question 5

Which of the following best describes the difference between leading and lagging strand synthesis during DNA replication?

Accepted Answer

The leading strand is synthesized continuously, while the lagging strand is synthesized in short fragments called Okazaki fragments.

Question 6

Which enzyme joins Okazaki fragments together on the lagging strand?

Accepted Answer

Ligase

Question 7

A mutation occurs that disables the proofreading function of DNA polymerase. What is the most likely consequence?

Accepted Answer

Increased rate of mutations during DNA replication

Question 8

Why do bacteria not require telomerase for DNA replication?

Accepted Answer

Their chromosomes are circular, so they do not have ends that shorten during replication.

Question 9

Which of the following is a direct result of the complementary base pairing in DNA?

Accepted Answer

The accurate replication of DNA during cell division

Question 10

A cell is exposed to UV radiation, causing thymine dimers to form. Which DNA repair mechanism is most likely to fix this damage?

Accepted Answer

Nucleotide excision repair

Question 11

If DNA polymerase could not distinguish between parent and daughter strands, which repair process would be most affected?

Accepted Answer

Mismatch repair

Question 12

Which of the following equations correctly represents the base pairing rule in DNA?

Accepted Answer

$$A = T$$ and $$G = C$$

Question 13

Which protein complex is responsible for synthesizing new DNA strands during replication?

Accepted Answer

Replisome

Question 14

A patient has a genetic disorder resulting in shortened telomeres. Which cellular process is most likely impaired?

Accepted Answer

Cell division

Question 15

Which enzyme relieves the tension ahead of the replication fork during DNA synthesis?

Accepted Answer

Topoisomerase

Question 16

Which of the following best explains why Okazaki fragments are formed during DNA replication?

Accepted Answer

DNA polymerase can only synthesize DNA in the 5' to 3' direction.

Question 17

Which of the following is NOT a function of DNA polymerase?

Accepted Answer

Joining Okazaki fragments

Question 18

Which process ensures that genetic information is passed accurately from one generation to the next?

Accepted Answer

Semiconservative replication

Question 19

A scientist observes that a cell accumulates mutations at a much higher rate than normal. Which repair mechanism is most likely defective?

Accepted Answer

Mismatch repair

Question 20

Which of the following statements about the Hershey-Chase experiment is correct?

Accepted Answer

It used radioactive isotopes to label DNA and protein in bacteriophages.

DNA Synthesis and Repair: Gene Structure, Replication, and Maintenance

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