Question 1

Which of the following is NOT a requirement for a molecule to serve as genetic material?

Accepted Answer

It must be able to allow variation by mutation.

Question 2

In the classic Griffith experiment with Streptococcus pneumoniae, what was the key finding?

Accepted Answer

A substance from heat-killed S cells transformed R cells into virulent S cells.

Question 3

Which experiment provided direct evidence that DNA, and not protein, is the genetic material in bacteriophages?

Accepted Answer

Hershey-Chase blender experiment using $$^{32}P$$ and $$^{35}S$$ labeling

Question 4

Which of the following correctly describes a phosphodiester bond in DNA?

Accepted Answer

A bond between the phosphate group at the C-5' position of one nucleotide and the OH group at the C-3' position of the next

Question 5

According to Chargaff's rules, which of the following is true for double-stranded DNA?

Accepted Answer

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

Question 6

Which feature distinguishes Z-DNA from B-DNA?

Accepted Answer

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

Question 7

What is the primary function of histone proteins in eukaryotic cells?

Accepted Answer

To package DNA into nucleosomes and regulate access to genetic information

Question 8

Which of the following best describes euchromatin?

Accepted Answer

It contains functional genes and is less condensed during interphase.

Question 9

A chromosome with the centromere located at the very end is called:

Accepted Answer

Telocentric

Question 10

Which of the following statements about homologous chromosomes is correct?

Accepted Answer

They carry genes for the same traits but may have different alleles.

Question 11

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

Accepted Answer

The accurate replication of genetic information

Question 12

Which of the following is true about the structure of the DNA double helix as described by Watson and Crick?

Accepted Answer

Each complete turn of the helix is 34 Å long and contains 10 base pairs.

Question 13

Which of the following best explains why proteins were initially thought to be the genetic material instead of DNA?

Accepted Answer

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

Question 14

Which of the following is a characteristic of polytene chromosomes?

Accepted Answer

They contain puff regions that are sites of active transcription.

Question 15

A DNA sample from a newly discovered organism contains 22% adenine. According to Chargaff's rules, what is the expected percentage of guanine?

Accepted Answer

28%

Question 16

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

Accepted Answer

A nucleotide contains a nitrogenous base, a pentose sugar, and a phosphate group.

Question 17

Which of the following is a function of telomeres?

Accepted Answer

They maintain chromosome integrity.

Question 18

Which of the following statements about chromatin is correct?

Accepted Answer

Chromatin consists of DNA and histone proteins organized into nucleosomes.

Question 19

Which of the following best describes the role of the nucleolus in eukaryotic cells?

Accepted Answer

It is where ribosomal RNA (rRNA) is synthesized.

Question 20

Which of the following is true regarding the packaging of DNA in eukaryotic cells?

Accepted Answer

DNA is packaged into nucleosomes, which are further folded into chromatin fibers and condensed into chromosomes.

Genetic Material: Structure and Organization

Study Guide - Practice Questions