Question 1

Which of the following is NOT a required characteristic of genetic material?

Accepted Answer

It must be able to photosynthesize.

Question 2

In the Hershey-Chase experiment, which radioactive isotope was used to label DNA, and why was this significant?

Accepted Answer

$$^{32}\mathrm{P}$$, because phosphorus is found in DNA but not in protein.

Question 3

Which experimental result from Griffith’s transformation experiments provided evidence for a 'transforming principle'?

Accepted Answer

Mice injected with living IIR and heat-killed IIIS bacteria died, and living IIIS bacteria were recovered.

Question 4

Which of the following is a purine found in DNA?

Accepted Answer

Adenine

Question 5

Why does DNA with a higher GC content have a higher melting temperature?

Accepted Answer

GC pairs form three hydrogen bonds, while AT pairs form two.

Question 6

Which of the following best describes the directionality of DNA polymerization?

Accepted Answer

Nucleotides are added to the 3' end of the growing strand.

Question 7

Which of the following is an example of direct evidence that DNA is the genetic material?

Accepted Answer

Recombinant DNA technology allows bacteria to express foreign genes.

Question 8

Which of the following statements about RNA is FALSE?

Accepted Answer

RNA is always double-stranded in cells.

Question 9

A sample of DNA is found to contain 30% adenine. According to Chargaff’s rules, what percentage of guanine would you expect?

Accepted Answer

20%

Question 10

Which type of RNA is the most abundant in cells and is a structural component of ribosomes?

Accepted Answer

rRNA

Question 11

Which of the following best explains why UV light at 260 nm is effective at inducing mutations in DNA?

Accepted Answer

DNA absorbs UV light maximally at 260 nm.

Question 12

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

Accepted Answer

DNA contains deoxyribose, RNA contains ribose.

Question 13

Which enzyme is required for the replication of RNA viruses such as Qβ phage in vitro?

Accepted Answer

RNA replicase

Question 14

Which of the following best describes the role of tRNA during translation?

Accepted Answer

It carries amino acids to the ribosome and matches them to the mRNA codon.

Question 15

Which of the following is a real-world application of gel electrophoresis?

Accepted Answer

Separating DNA fragments by size for forensic analysis.

Question 16

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

Accepted Answer

The two strands are antiparallel and held together by hydrogen bonds between purines and pyrimidines.

Question 17

Which of the following is an example of indirect evidence that DNA is the genetic material?

Accepted Answer

DNA is present in mitochondria and chloroplasts, which have genetic functions.

Question 18

A retrovirus contains which of the following enzymes that allows it to convert its RNA genome into DNA?

Accepted Answer

Reverse transcriptase

Question 19

Which of the following best explains why protein was initially considered a better candidate for genetic material than DNA?

Accepted Answer

Proteins are composed of 20 different amino acids, allowing for greater variation.

Question 20

Which of the following bonds is responsible for linking nucleotides together in a single strand of DNA?

Accepted Answer

Phosphodiester bonds

DNA Structure and Analysis: Foundations of Genetic Material

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