$$\text{O}-\text{P}-\text{O}-\text{C}$$

Question 1

Which experiment first demonstrated that DNA is the genetic material responsible for transformation in bacteria?

Accepted Answer

Avery, McLeod, and McCarty's experiment using enzymatic treatments

Question 2

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

Accepted Answer

$$^{32}P$$ ; DNA is the genetic material

Question 3

Which structural feature distinguishes ribose from deoxyribose in nucleic acids?

Accepted Answer

Ribose has an OH group at the 2' carbon

Question 4

Which nitrogenous bases are classified as purines?

Accepted Answer

Adenine and guanine

Question 5

What is the chemical bond that links nucleotides together in a DNA strand?

Accepted Answer

Phosphodiester bond

Question 6

In Griffith's experiment, what was the outcome when mice were injected with a mixture of heat-killed S strain and live R strain bacteria?

Accepted Answer

The mice died and S strain was recovered

Question 7

Which enzyme treatment in Avery, McLeod, and McCarty's experiment prevented transformation, indicating the genetic material?

Accepted Answer

DNase

Question 8

Which of the following best describes the physical property of DNA that allows it to be visualized by electron microscopy?

Accepted Answer

Its double helix structure and length

Question 9

What is the structural unit of chromatin in eukaryotic cells?

Accepted Answer

Nucleosome

Question 10

Which histone is known as the 'linker' histone in chromatin structure?

Accepted Answer

H1

Question 11

A viral genome can be single-stranded or double-stranded, linear or circular. Which property distinguishes viral DNA from bacterial DNA?

Accepted Answer

Viral DNA can be inert while packaged

Question 12

Which chemical modification of histones is most commonly associated with chromatin remodeling?

Accepted Answer

Acetylation

Question 13

If a DNA molecule is composed of 30% adenine, what percentage of guanine would you expect according to Chargaff's rules?

Accepted Answer

20%

Question 14

Which of the following is NOT a component of a nucleotide?

Accepted Answer

Carboxyl group

Question 15

Which real-world application relies on the ability to distinguish DNA from protein using radioactive labeling, as in the Hershey-Chase experiment?

Accepted Answer

Gene therapy using viral vectors

Question 16

Which formula represents the phosphodiester bond between two nucleotides?

Accepted Answer

$$	ext{O}-	ext{P}-	ext{O}-	ext{C}$$

Question 17

Which scenario best illustrates the transformation principle as described by Griffith?

Accepted Answer

A mouse injected with live R strain and heat-killed S strain dies, and S strain is recovered

Question 18

Which property of histones allows them to interact strongly with DNA?

Accepted Answer

They are rich in arginine and lysine

Question 19

Which of the following best describes the organization of eukaryotic chromatin during interphase?

Accepted Answer

Chromatin is associated with histones and forms nucleosomes

Question 20

Which of the following is a correct description of a nucleoside triphosphate (NTP)?

Accepted Answer

A nitrogenous base, a pentose sugar, and three phosphate groups

DNA Structure, Function, and Experimental Evidence: Study Notes for Genetics Students

Study Guide - Practice Questions