Question 1

Which of the following best explains why RNA is generally more reactive and less stable than DNA?

Accepted Answer

RNA has a ribose sugar with a hydroxyl group at the 2' carbon, increasing reactivity.

Question 2

During DNA replication in eukaryotic cells, what is the primary challenge associated with replicating the ends of linear chromosomes?

Accepted Answer

The removal of RNA primers at the ends leaves a gap that cannot be filled, leading to telomere shortening.

Question 3

Which of the following statements correctly describes the directionality of DNA synthesis?

Accepted Answer

DNA polymerase synthesizes new DNA in the 5' to 3' direction.

Question 4

In a double-stranded DNA molecule, why do purines always pair with pyrimidines?

Accepted Answer

Purine-pyrimidine pairs maximize hydrogen bonding and maintain consistent helix geometry.

Question 5

Which of the following is NOT a required component for a polymerase chain reaction (PCR)?

Accepted Answer

RNA polymerase

Question 6

A DNA sample is heated and shows no change in region A, but regions B and C denature. What can you infer about the base composition of region A compared to B and C?

Accepted Answer

Region A is less AT-rich (more GC-rich) than regions B and C.

Question 7

Which enzyme is responsible for synthesizing new DNA strands during replication in vivo?

Accepted Answer

DNA polymerase

Question 8

What is the main function of telomerase in eukaryotic cells?

Accepted Answer

To extend the telomeres and prevent chromosome shortening.

Question 9

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

Accepted Answer

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

Question 10

Which of the following is a correct representation of the chemical reaction for adding a nucleotide to a growing DNA strand?

Accepted Answer

$$\mathrm{(DNA)_{n}} + dNTP \rightarrow (DNA)_{n+1} + PP_i$$

Question 11

Which of the following statements about PCR is correct?

Accepted Answer

PCR uses cycles of heating and cooling to denature DNA, anneal primers, and elongate new strands.

Question 12

Which feature of the DNA double helix allows proteins to bind in a sequence-specific manner?

Accepted Answer

The major and minor grooves formed by the twisting of the backbone.

Question 13

Which of the following best describes the role of primers in PCR?

Accepted Answer

Primers determine the specific region of DNA to be amplified by providing a starting point for DNA polymerase.

Question 14

Which of the following is a unique property of ribozymes compared to other RNA molecules?

Accepted Answer

They have catalytic activity and can facilitate chemical reactions.

Question 15

Which of the following correctly matches the base pairing in DNA?

Accepted Answer

Adenine pairs with thymine, guanine pairs with cytosine.

Question 16

Which of the following is a difference between DNA and RNA nucleotides?

Accepted Answer

DNA nucleotides contain thymine, while RNA nucleotides contain uracil.

Question 17

In the context of DNA replication, what is the function of helicase?

Accepted Answer

To unwind the DNA double helix, separating the two strands.

Question 18

Which of the following best describes the process of denaturation in PCR?

Accepted Answer

The double-stranded DNA is separated into single strands by heating.

Question 19

Which of the following equations correctly represents the relationship between the number of adenine and thymine bases in double-stranded DNA?

Accepted Answer

$$[A] = [T]$$

Nucleic Acids, DNA Structure, and DNA Replication: Study Notes for General Biology

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드