Reference no: EM1388290

The x-ray diffraction photography of Rosalind Franklin and Maurice was critical evidence of DNA
a. indicating that DNA has a double helix structure
b. showing equal number of purines and pyrimidines
c. revealing the location of each adenine, guanine, cytosine, and thymine
d. showing the bases of DNA were held together by hydrogen bonds
e. revealing the structure of the deoxyribose sugar
In the Watson and Crick model of DNA, the steps of the ladder are composed of
a. a sugar and a phosphate molecule
b. a purine and a pyrimidine
c. two purines
d. two pyrimidines
e. sugars
The structure of DNA is most like a
a. None of the answers
b. double helix
c. double triangle
d. double ellipse
e. figure eight
Which of the following is Not a proper base pairing for DNA?
a. A - C
b. All of the answers
c. C - A
d. G - T
e. T - G
Starting with 15N15N (heavy) DNA, and after THREE generations in the 14N medium, E. coli cells will produce the following band(s) in density-gradient centrifugation:
a. one band of heavy DNA and one band of light DNA
b. a single band of DNA with medium density
c. three bands corresponding to DNA of light, medium and heavy density
d. one band of light DNA and one band of DNA with medium density
e. one band of heavy DNA and one band of DNA with medium density
The Meselson-Stahl experiment demonstrated that DNA replication produces two DNA molecules each composed of
a. two strands with variable proportions of new and old DNA
b. a variable number of old and new strands
c. one old and one new strand
d. two new strands
e. two old strands
Which statement is false?
a. Each nucleotide is composed of a five-carbon sugar, a phosphate group, and either a purine or a pyrimidine.
b. Protein molecules contain no phosphorus.
c. Viruses are particles of nucleic acid encased in protein.
d. Hershey and Chase discovered that 35S and not 32P had been incorporated into the hereditary system of the bacteria.
e. Bacteriophages are viruses that inject their nucleic acid genetic code into bacteria and use the bacterial genetic apparatus to make viral proteins.
Hershey and Chase experimented with radioactively labeled phosphorus and sulfur to determine that DNA and not protein is the genetic material. Which of the following was essential to this confirming experiment?
a. Sulfur is present in amino acids in the protein coat of bacteria
b. Phosphorus is present in high amounts in DNA
c. All of the answers were critical to demonstrating DNA is involved in genetic material
d. Sulfur is not present in DNA
e. Phosphorus is not present in amino acids in the protein coat of bacteria
Which of the following is Not one of the four bases that makes up DNA?
a. adenine
b. guanine
c. uraciL
d. thymine
e. cytosine
If a mixture of viruses labeled with radioactive sulfur and phosphorus is placed in a bacterial culture,
a. the bacteria will internalize both radioactive sulfur and phosphorus.
b. the bacteria will internalize radioactive sulfur.
c. the bacteria will not internalize either sulfur or phosphorus.
d. the bacteria will internalize radioactive phosphorus.
e. the viruses will not attach to the bacteria.
The correct structure of DNA is a/an
a. octagon
b. diamond
c. single strand
d. double helix
Which scientist(s) identified the transforming substance involved in changing R bacteria to S?
a. Pauling
b. Griffith
c. Hershey and Chase
d. Chargaff
e. Avery