$$\text{DNA} \rightarrow \text{RNA} \rightarrow \text{Protein}$$

Question 1

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

Accepted Answer

Hershey and Chase's experiment using radioactive sulfur ($$^{35}S) $$and phosphorus ($$^{32}P)$$

Question 2

In the flow of genetic information within a cell, which sequence correctly represents the central dogma?

Accepted Answer

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

Question 3

Which scientist first discovered the substance now known as DNA in 1869?

Accepted Answer

Johann Friedrich Miescher

Question 4

What was the key finding from Griffith's experiment with S-strain and R-strain bacteria in mice?

Accepted Answer

A substance from dead S-strain bacteria could transform live R-strain into pathogenic S-strain

Question 5

Avery, MacLeod, and McCarty demonstrated that the transforming principle was DNA by showing that:

Accepted Answer

DNA digestion prevented transformation

Question 6

During the Hershey-Chase experiment, which radioactive label was found inside the bacterial cells after infection?

Accepted Answer

$$^{32}P ($$phosphorus)

Question 7

Which of the following best describes the role of reverse transcriptase in retroviruses?

Accepted Answer

It synthesizes complementary DNA from viral RNA

Question 8

What is the correct definition of a gene according to the study materials?

Accepted Answer

A unit of hereditary information that consists of DNA and codes for functional products, usually proteins

Question 9

Which statement about the lytic and lysogenic cycles of bacteriophages is correct?

Accepted Answer

Virulent phages undergo lytic growth, while temperate phages can integrate their DNA into the host chromosome

Question 10

In the context of viral genetics, which virus uses RNA as its genetic material and requires reverse transcriptase for replication?

Accepted Answer

HIV (human immunodeficiency virus)

Question 11

Which process describes the synthesis of RNA from a DNA template?

Accepted Answer

Transcription

Question 12

What is the function of messenger RNA (mRNA) in the flow of genetic information?

Accepted Answer

It directs the synthesis of polypeptides during translation

Question 13

Which of the following best explains why scientists originally thought proteins were the genetic material?

Accepted Answer

Proteins are more complex and diverse in structure than DNA

Question 14

In the experiment with tobacco mosaic virus (TMV), what determined the type of lesion on the plant?

Accepted Answer

The type of RNA present

Question 15

Which of the following is TRUE about the replication of proviral DNA in retroviruses?

Accepted Answer

It is replicated every time the host cell replicates its own DNA

Question 16

Which macromolecules were present in the mixture after Avery's group used heat to kill smooth streptococcal cells?

Accepted Answer

Carbohydrates, lipids, proteins, and nucleic acids

Question 17

Which step in the retrovirus life cycle involves the enzyme reverse transcriptase?

Accepted Answer

Synthesis of a DNA strand complementary to viral RNA

Question 18

If a mutation prevents the transcription of DNA, which process would be directly affected?

Accepted Answer

Synthesis of proteins

Question 19

Which of the following best describes the role of nuclein as discovered by Miescher?

Accepted Answer

It is the substance now known as DNA

Question 20

A temperate phage differs from a virulent phage in that:

Accepted Answer

It can integrate its DNA into the host chromosome and remain dormant

Chapter 16: The Structural Basis of Cellular Information—DNA, Chromosomes, and the Nucleus

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