Question 1

Which of the following is NOT one of the four essential characteristics that a molecule must exhibit to serve as genetic material?

Accepted Answer

It must be able to catalyze protein synthesis.

Question 2

In the Hershey-Chase experiment, which radioactive isotope was used to label DNA, and what was the main conclusion of the experiment?

Accepted Answer

$$^{32}\mathrm{P}$$; DNA is the genetic material that enters the bacterial cell and directs viral reproduction.

Question 3

Which experimental result provided the first direct evidence that DNA, and not protein, is the biomolecule responsible for heredity?

Accepted Answer

Avery, MacLeod, and McCarty's use of DNase to destroy transforming activity in bacteria.

Question 4

Which of the following statements about the structure of DNA is correct?

Accepted Answer

Guanine pairs with cytosine via three hydrogen bonds.

Question 5

Which property of nucleic acids was used as indirect evidence that DNA is the genetic material, based on mutagenesis experiments?

Accepted Answer

DNA absorbs UV light most strongly at 260 nm, which matches the wavelength most effective at inducing mutations.

Question 6

Which of the following best describes the difference between a nucleoside and a nucleotide?

Accepted Answer

A nucleoside contains a nitrogenous base and a pentose sugar; a nucleotide also contains a phosphate group.

Question 7

Which of the following is a unique feature of Z-DNA compared to B-DNA?

Accepted Answer

Z-DNA is a left-handed double helix, while B-DNA is right-handed.

Question 8

Which enzyme is responsible for synthesizing DNA from an RNA template in retroviruses?

Accepted Answer

Reverse transcriptase

Question 9

A sample of double-stranded DNA is found to contain 30% adenine. What percentage of guanine would you expect to find?

Accepted Answer

20%

Question 10

Which of the following analytical techniques is used to separate DNA fragments by size?

Accepted Answer

Electrophoresis

Question 11

Which of the following best explains why proteins were initially favored as the genetic material over DNA?

Accepted Answer

Proteins are more chemically diverse and abundant than DNA.

Question 12

Which of the following is a direct evidence that DNA is the genetic material in eukaryotes?

Accepted Answer

Production of human insulin in bacteria containing recombinant human DNA.

Question 13

Which of the following statements about RNA is FALSE?

Accepted Answer

RNA contains the sugar deoxyribose.

Question 14

Which bond links nucleotides together in a DNA strand?

Accepted Answer

Phosphodiester bond

Question 15

Which of the following best describes the central dogma of molecular genetics?

Accepted Answer

$$	ext{DNA} ightarrow 	ext{RNA} ightarrow 	ext{Protein}$$

Question 16

Which of the following is a function of tRNA during gene expression?

Accepted Answer

Carrying amino acids to the ribosome for protein synthesis.

Question 17

Which of the following statements about alternative forms of DNA is correct?

Accepted Answer

A-DNA is more compact than B-DNA and is prevalent under high-salt or dehydration conditions.

Question 18

Which of the following best describes the process of molecular hybridization?

Accepted Answer

The denaturation and renaturation of nucleic acids to allow complementary strands to pair.

Question 19

Which of the following is a real-world application of recombinant DNA technology that provides direct evidence for DNA as the genetic material?

Accepted Answer

Production of human interferon in bacteria.

Question 20

Which class of RNA is directly involved in processing mRNA in eukaryotes?

Accepted Answer

Small nuclear RNA (snRNA)

DNA Structure and Analysis – Genetics Study Notes

Study Guide - Practice Questions