Question 1

Which experiment provided the first evidence that DNA is the genetic material responsible for inheritance?

Accepted Answer

Griffith's experiment with Streptococcus pneumoniae

Question 2

In the Hershey and Chase experiment, why was radioactive phosphorus ($$^{32}P) $$used to label DNA?

Accepted Answer

Because DNA contains phosphorus but not sulfur

Question 3

What is the phenomenon called when a non-pathogenic bacterial strain acquires genetic material from a dead pathogenic strain and becomes pathogenic?

Accepted Answer

Transformation

Question 4

If the result of the Hershey and Chase experiment had been that radioactive sulfur ($$^{35}S) $$was found inside the cells instead of radioactive phosphorus ($$^{32}P$$), what could have been concluded?

Accepted Answer

Protein, not DNA, is the genetic material

Question 5

Which component of a nucleotide is responsible for its acidic properties?

Accepted Answer

Phosphate group

Question 6

A bacteriophage consists of which of the following components?

Accepted Answer

DNA wrapped in a protein coat

Question 7

Which of the following best describes pathogenic bacteria?

Accepted Answer

Bacteria that can cause disease in a host

Question 8

In Griffith's experiment, which result demonstrated the concept of transformation?

Accepted Answer

Mouse dies after being injected with a mixture of heat-killed S and living R cells

Question 9

Which molecule was ultimately identified as the 'transforming substance' in the experiments by Avery, MacLeod, and McCarty?

Accepted Answer

DNA

Question 10

Why did many scientists initially doubt that DNA was the genetic material?

Accepted Answer

DNA was thought to be too simple, with only four subunits

Question 11

Which radioactive isotope was used to label protein in the Hershey and Chase experiment?

Accepted Answer

$$^{35}S$$

Question 12

What is the correct sequence for the flow of genetic information in a cell?

Accepted Answer

DNA $$\rightarrow$$ RNA $$\rightarrow$$ Protein

Question 13

Which process describes the assimilation of external DNA into a bacterial cell?

Accepted Answer

Transformation

Question 14

In the Hershey and Chase experiment, what was found in the pellet after centrifugation in the batch with $$^{32}P-$$labeled phages?

Accepted Answer

Radioactive DNA

Question 15

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

Accepted Answer

Lipid

Question 16

A scientist wants to determine whether a molecule is DNA or protein. Which element should she look for to distinguish DNA from protein?

Accepted Answer

Phosphorus

Question 17

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

Accepted Answer

Protein has 20 different subunits, allowing for greater diversity

Question 18

Which step in the Hershey and Chase experiment ensured that only the genetic material entering the cell was measured?

Accepted Answer

Agitation to remove phages attached to the outside of bacteria

Question 19

Which of the following is a plausible explanation for why heat-killed S cells did not cause disease in mice?

Accepted Answer

The genetic material was destroyed by heat

Question 20

If a mixture of heat-killed S cells and living R cells is injected into a mouse and the mouse dies, what does this indicate about the R cells?

Accepted Answer

R cells have acquired genetic material from S cells and become pathogenic

The Discovery of DNA as the Genetic Material

Study Guide - Practice Questions

Study Guide - Flashcards