Ch 13-1

Question 1

Who discovered bacterial transformation

Answer 1

Frederick Griffith

Question 2

What did Avery, MacLeod, and McCarty prove in 1944?

Answer 2

DNA was the material passed during bacterial transformation

Question 3

Who designed an experiment to determine whether the genetic material of T2 phage was protein or DNA?

Answer 3

Alfred Hershey and Martha Chase

Question 4

What did Erwin Chargaff’s research on DNA composition reveal?

Answer 4

Different organisms have different proportions of each base, and there are even proportions of adenine-thymine and cytosine-guanine

Question 5

What technique was used to study the structures of biomolecules, including DNA?

Answer 5

X-ray crystallography

Question 6

Who collected the X-ray crystallography data that visually showed DNA’s helical structure?

Answer 6

Rosalind Franklin

Question 7

Who are often credited for elucidating the 3D structure of DNA?

Answer 7

James Watson and Francis Crick

Question 8

What is the term for DNA combined with proteins?

Answer 8

Chromatin

Question 9

What is the difference between heterochromatin and euchromatin?

Answer 9

Heterochromatin is highly condensed and mostly inaccessible, while euchromatin is more dispersed and contains actively transcribed regions

Question 10

In what year did Watson and Crick publish their 1-page report on the 3D structure of DNA?

Answer 10

1953

Question 11

The S (smooth) strain of Streptococcus pneumoniae has a ______ which protects it from the immune system and is pathogenic.

Answer 11

Capsule

Question 12

Transformation can be defined as the alteration of ______ and ______ due to the assimilation of external DNA.

Answer 12

Genotype, phenotype

Question 13

A ______ is a virus which infects bacteria.

Answer 13

Answer: bacteriophage

Question 14

DNA is composed of ______ different bases.

Answer 14

4

Question 15

Watson & Crick determined that the two strands of DNA are ______.

Answer 15

Anti parallel

Question 16

The sequence of bases along the DNA molecule accounted for the large amount of ______ seen.

Answer 16

Diversity

Question 17

DNA packaging plays an important role in both the organization and ______ of expression of genetic material.

Answer 17

Regulation

Question 18

_____ is highly condensed and mostly inaccessible to transcription machinery.

Answer 18

Heterochromatin

Question 19

______ is more dispersed and contains accessible regions which are actively transcribed.

Answer 19

Euchromatin

Question 20

Watson, Crick, and Wilkins were awarded the Nobel Prize in ______.

Answer 20

1962

Question 21

Which strain of Streptococcus pneumoniae lacks a capsule and is nonpathogenic?
a) S strain
b) R strain
c) T strain
d) P strain

Answer 21

B

Question 22

Who proved that DNA was the material passed during bacterial transformation?
a) Griffith
b) Watson and Crick
c) Avery, MacLeod, and McCarty
d) Hershey and Chase

Answer 22

C

Question 23

What did Hershey and Chase’s experiment show?
a) Only protein enters bacterial cells during T2 phage infection
b) Only DNA enters bacterial cells during T2 phage infection
c) Both DNA and protein enter bacterial cells during T2 phage infection
d) Neither DNA nor protein enters bacterial cells during T2 phage infection

Answer 23

B

Question 24

What did Chargaff’s research reveal about DNA composition?
a) All organisms have the same proportions of each base
b) There are uneven proportions of adenine-thymine and cytosine-guanine
c) Different organisms have different proportions of each base
d) DNA is composed of only three bases

Answer 24

C

Question 25

What technique was used to study the structure of DNA? a) Electron microscopy b) X-ray crystallography c) Nuclear magnetic resonance d) Mass spectrometry

Answer 25

B

Question 26

Who collected the X-ray crystallography data that showed DNA's helical structure? a) Watson and Crick b) Rosalind Franklin c) Erwin Chargaff d) Maurice Wilkins

Answer 26

B

Question 27

What did Watson and Crick determine about the two strands of DNA? a) They are parallel b) They are antiparallel c) They are perpendicular d) They are unconnected

Answer 27

B

Question 28

What is the combination of DNA and proteins called? a) Nucleosome b) Histone c) Chromatin d) Chromosome

Answer 28

C

Question 29

Which type of chromatin is more dispersed and contains actively transcribed regions? a) Heterochromatin b) Euchromatin c) Mesochromatin d) Isochromatin

Answer 29

B

Question 30

In what year did Watson and Crick publish their report on the 3D structure of DNA? a) 1951 b) 1952 c) 1953 d) 1954

Answer 30

C

Question 31

Proteins were initially believed to be the likely candidate for hereditary material.

Answer 31

T

Question 32

Bacterial transformation was discovered by Avery, MacLeod, and McCarty.

Answer 32

False. Bacterial transformation was discovered by Frederick Griffith.

Question 33

The Hershey-Chase experiment showed that only protein enters bacterial cells during T2 phage infection.

Answer 33

False. The Hershey-Chase experiment showed that only DNA enters bacterial cells during T2 phage infection.

Question 34

Erwin Chargaff found that different organisms have the same proportions of each DNA base.

Answer 34

False. Chargaff found that different organisms have different proportions of each DNA base.

Question 35

X-ray crystallography was used to study the structure of DNA.

Answer 35

T

Question 36

James Watson and Francis Crick are solely responsible for elucidating the 3D structure of DNA.

Answer 36

False. Their discovery involved combining the work of other scientists, including Chargaff and Franklin.

Question 37

The two strands of DNA are parallel to each other.

Answer 37

False. The two strands of DNA are antiparallel.

Question 38

The sequence of bases in DNA accounts for the large amount of genetic diversity seen.

Answer 38

T

Question 39

Heterochromatin is more dispersed and contains actively transcribed regions.

Answer 39

False. Euchromatin is more dispersed and contains actively transcribed regions, while heterochromatin is highly condensed.

Question 40

Rosalind Franklin was awarded the Nobel Prize along with Watson, Crick, and Wilkins.

Answer 40

F