The Living World 9th Edition By George Johnson – Test Bank

Chapter 11 Test Bank Key

1. The building blocks of DNA are called

A. proteins.

B. bases.

C. nucleotides.

D. acids.
DNA is a polymer of nucleotides, which are made of a nitrogenous base, deoxyribonucleic sugar and a phosphate group.

Accessibility: Keyboard Navigation
Blooms Level: 1. Remember
Learning Objective: 11.03.01 Explain why each nucleotide in Watson and Crick’s DNA structure can form a base pair with only one of the four potential nucleotides.
Section: 11.03
Topic: DNA/Chromosome Structure

2. The significance of the Griffith, Avery, and Hershey-Chase experiments was that they demonstrated that

A. genes were located on chromosomes.

B. enzymes transformed bacteria.

C. proteins were what genes were composed of.

D. DNA was the molecule of heredity.
The experiments done by Griffith, Avery and Hershey-Chase experiments ultimately helped to show that DNA is the molecule of heredity.

Accessibility: Keyboard Navigation
Blooms Level: 1. Remember
Learning Objective: 11.01.01 Explain why Griffith’s mixture of harmless dead bacteria possessing capsules and harmless live bacteria lacking capsules is pathogenic.
Learning Objective: 11.02.01 List the five ways that Avery’s transforming principle resembles DNA.
Learning Objective: 11.02.02 Explain how the Hershey-Chase experiment demonstrates that DNA is the hereditary material.
Section: 11.02
Topic: The Nature of the Genetic Material

3. Which scientist’s work first suggested that DNA had the shape of a helix?

A. Rosalind Franklin

B. James Watson

C. Martha Chase

D. Francis Crick
Rosalind Franklin made the X-ray diffraction image that showed DNA was helical in shape.

4. A plant species has its DNA analyzed. The results show that 28% of its nitrogen bases are guanine. What is the percent represented by thymine?

A. 28%

B. 56%

C. 23%

D. 22%
The base pairing rules state that A=T and C=G.

Accessibility: Keyboard Navigation
Blooms Level: 3. Apply
Learning Objective: 11.03.01 Explain why each nucleotide in Watson and Crick’s DNA structure can form a base pair with only one of the four potential nucleotides.
Section: 11.03
Topic: DNA/Chromosome Structure

5. Hershey and Chase tagged the DNA of viruses with radioactive phosphorus, and their protein coats with radioactive sulfur. When the viruses were allowed to infect bacteria, what did the viruses transfer to the bacteria?

A. radioactive phosphorus and sulfur

B. radioactive sulfur

C. radioactive phosphorus

D. neither radioactive phosphorus nor sulfur
The viruses transferred just the radioactive phosphorus because just the DNA (containing the phosphorus) is transferred from the virus to bacterial cell.

Accessibility: Keyboard Navigation
Blooms Level: 2. Understand
Learning Objective: 11.02.02 Explain how the Hershey-Chase experiment demonstrates that DNA is the hereditary material.
Section: 11.02
Topic: The Nature of the Genetic Material

6. Biochemist Erwin Chargaff found that in DNA there was a special relationship between individual bases that we now refer to as Chargaff’s rule. His observation was that

A. A = T and G = C.

B. C = T and A = G.

C. A + T = C + G.

D. G = T and C = A.
After analyzing DNA from a many different species, Erwin Chargaff found that the number of A molecules always equals the number of T molecules and the number of G molecules is always equal to the number of C molecules.

7. If one strand of a DNA molecule has the base sequence ATTGCAT, its complementary strand will have the sequence

A. ATTGCAT.

B. TAACGTA.

C. GCCATGC.

D. CGGTACG.
The base pairing rules that A always base pairs with T and C with G.

Accessibility: Keyboard Navigation
Blooms Level: 2. Understand
Learning Objective: 11.03.01 Explain why each nucleotide in Watson and Crick’s DNA structure can form a base pair with only one of the four potential nucleotides.
Section: 11.03
Topic: DNA/Chromosome Structure

8. Meselson and Stahl proved that

A. DNA is the genetic material.

B. DNA is made from nucleotides.

C. DNA replicates in a semi-conservative manner.

D. DNA contains nitrogen.
The Meselson-Stahl experiment clearly showed that the method of DNA replication is semi-conservative: one old (parent) strand and another new (daughter) strand.

Accessibility: Keyboard Navigation
Blooms Level: 1. Remember
Learning Objective: 11.04.02 Explain how the Meselson-Stahl experiment confirms one of the three hypotheses of DNA replication.
Section: 11.04
Topic: DNA Replication

9. When Frederick Griffith infected mice with a virulent strain of Streptococcus pneumoniae, the mice

A. remained healthy.

B. died from pneumonia.

C. became ill but lived.

D. reproduced quicker.
The virulent strain of Streptococcus pneumoniae, when injected into healthy mice, caused pneumonia and hence, the mice died.

Accessibility: Keyboard Navigation
Blooms Level: 2. Understand
Learning Objective: 11.01.01 Explain why Griffith’s mixture of harmless dead bacteria possessing capsules and harmless live bacteria lacking capsules is pathogenic.
Section: 11.01
Topic: The Nature of the Genetic Material

10. When Frederick Griffith infected mice with S. pneumoniae that lacked a capsule, the mice

A. remained healthy.

B. died of penumonia.

C. became ill but lived.

D. reproduced quicker.
When Frederick Griffith infected mice with S. pneumoniae that lacked a capsule, the mice continued to live as this bacteria was non-pathogenic.