Download DNA Quiz - BiologySemester58

Name: __________________
Knowledge & Understanding:
Thinking & Investigation:
DNA Quiz
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Part A: Knowledge & Understanding-Multiple Choice (20 marks)
Select the best answer from the choices provided. Indicate your selection on the
quiz paper.
____
1. The paired bases of a DNA molecule are best described as
a. Covalently linked across the width of the double helix
b. Identical
c. Mirror images
d. Complementary
e. Single-stranded
____
2. The nucleotide at the end of one strand of a fragment of double-stranded DNA has a free phosphate
attached to the 5' carbon of its deoxyribose sugar. The complementary nucleotide has
a. A free phosphate attached to the 3' carbon of its deoxyribose sugar
b. A hydroxyl group (-OH) attached to the 3' carbon of its deoxyribose sugar
c. A free phosphate attached to the 5' carbon of its deoxyribose sugar
d. A hydroxyl group attached to the 5' carbon of its deoxyribose sugar
e. Two hydrogen atoms attached to the 3' carbon of its deoxyribose sugar
____
3. If the percentage composition of thymine in a DNA molecule is 22%, what is the percentage
composition of cytosine?
a. 28%
d. 22%
b. 32%
e. 18%
c. 26%
____
4. During DNA replication, the function of RNA primers is to
a. Open replication bubbles
b. Serve as starting points for DNA strand elongation by DNA polymerase I in the 3' 5' direction
c. Serve as starting points for DNA strand elongation by DNA polymerase III in
prokaryotes
d. Prevent new-separated strands of DNA from rejoining
e. Serve as a binding site for DNA ligase
____
5. During DNA replication, one of the new strands of DNA is synthesized continuously, while the other is
synthesized as a number of separate fragments of DNA that are subsequently linked by DNA ligase.
This is because
a. Replication starts at many points on the chromosome
b. RNA primers only anneal to one of the parental strands of DNA
c. DNA polymerase III only synthesizes DNA in the 3' - 5' direction
d. One of the parental strands is unwound slower than the other by helicase
e. DNA polymerase III only synthesizes DNA in the 5' - 3' direction
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____
6. In
a.
b.
c.
1869, Miescher extracted nuclein from
Slime mould
Pus cells
Bacterial cells
d. Red blood cells
e. Viruses
____
7. Which of the following statements concerning Griffith's work with Streptococcus pneumoniae is
incorrect?
a. Injected heat-killed S-form bacteria allowed mice to survive
b. Injected heat-killed S-form bacteria together with live R-form bacteria killed mice
c. Injected S-form bacteria killed mice
d. Injected R-form bacteria killed mice
e. The S-form bacteria are enveloped with a capsule of polysaccharide and appear as
smooth colonies
____
8. Hershey and Chase's experiment
a. Was intended to demonstrate that the protein case of a bacteriophage remained
outside a bacterial cell after infection.
b. Involved finding radioactivity inside bacteria infected with bacteriophage having
DNA labeled with 32P.
c. Involved finding radioactivity inside bacteria infected with bacteriophage having
DNA labeled with 35S.
d. Involved finding radioactivity inside bacteria infected with bacteriophage having
protein labeled with 32P.
e. Involved finding radioactivity inside bacteria infected with bacteriophage having
protein labeled with 35S.
____
9. A DNA nucleotide contains
1. A cyclic nitrogen-containing part
2. A single ring containing five carbons
3. A part that contains four oxygen atoms surrounding a central atom.
In order, 1, 2 and 3 are
a. A base, a phosphate group, a sugar
b. A sugar, a base, a phosphate group
c. A base, a sugar, a phosphate group
d. A phosphate group, a sugar, a base
e. A sugar, a phosphate group, a base
____ 10. The main support to the DNA molecule is provided by two backbones, which run along the two sides of
the double helix. These backbones consist of
a. Sugars joined by ester links
b. Phosphates joined by ester links
c. Sugars and phosphates linked together
d. Phosphates and bases linked together
e. Sugars and bases linked together
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____ 11. 5 ' G G C AT A (X )
(Z ) CC G T AT ( Y)
If the above is a representation of a piece of double-stranded DNA, what symbols should occupy the
positions (X), (Y) and (Z)?
a. 3',3',5'.
b. 5',3',3'
c. 5',3',5'
d. 5',5',3'
e. 3',5',3'
____ 12. The following three activities were engaged in by three different scientists (or groups of scientists)
who helped to determine the nature of the hereditary material
1. Transformation in bacteria
2. Research to identify what part of a bacteriophage is injected into a host bacterial cell
3. X-ray diffraction analysis of the DNA molecule
The scientist(s) who engaged in these activities are, respectively,
a. Griffith, Franklin, Watson and Crick
b. Hammerling, Hershey and Chase, Watson and Crick
c. Watson and Crick, Hershey and Chase, Hammerling
d. Griffith, Hershey and Chase, Franklin
e. Griffith, Hammerling, Franklin
____ 13. Frederick Griffith discovered
a. The structure of DNA
b. Transformation
c. Base complementarity
d. Virulence
e. Bacterial capsules
____ 14. The DNA double helix makes a complete turn every
a. 0.34 nm
d. 0.12 nm
b. 3.4 nm
e. 12 nm
c. 34 nm
____ 15. In their experiment that showed that DNA replication in E. coli was semi-conservative, Meselson and
Stahl used
a. A radioactive isotope of nitrogen
b. Nitrogen isotopes having different mass
c. Ultraviolet light
d. Radioactive phosphorus
e. Nitrogen isotopes which had different numbers of protons
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____ 16. In
1.
2.
3.
4.
a.
b.
c.
what order do the following molecules become involved in DNA replication in E. coli?
Single-stranded binding proteins
DNA polymerase III
Primase
Helicase
4,1,3,2
d. 3,2,4,1
4,3,1,2
e. 2,3,4,1
1,3,4,2
____ 17. An enzyme, which excises a mismatched base in a newly synthesized strand of DNA, is called
a. A primase
d. An exonuclease
b. A excisase
e. A gyrase
c. A polymerase
____ 18. A mutant form of E. coli has been discovered in which replication is unsuccessful because the RNA
primer is not released from the template strand. Which enzyme do you think is nonfunctional?
a. DNA polymerase III
d. Helicase
b. Primase
e. DNA polymerase I
c. Ligase
____ 19. What was the role of Avery, McCarty and Macleod in developing an understanding of the role of DNA
in heredity?
a. They discovered transformation.
b. They demonstrated that the nucleus was necessary for cell regeneration.
c. They defined the dimensions of the DNA molecule.
d. They identified DNA as the agent responsible for transformation.
e. They identified the nature of the genetic material released by a bacteriophage into
the cell it is infecting.
____ 20. In DNA, phosphodiester bonds join
a. Two phosphate groups
b. Bases and sugars
c. Phosphate groups and sugars
d. Phosphate groups and bases
e. Two sugar molecules
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Part B: Knowledge & Understanding-True/False (4 marks)
Indicate whether the sentence or statement is True (T) or False (F). Indicate your
selection on the quiz paper.
____ 21. In addition to the DNA in the nucleus, DNA is also found in the chloroplasts and mitochondria of
eukaryotic cells.
____ 22. Maurice Wilkins used X-ray crystallography on DNA fibres, which suggested that DNA was helical in
structure.
____ 23. Chargaff's rules state that in DNA, the totaled proportions of adenine and thymine always equal the
totaled proportions of guanine and cytosine.
____ 24. The three enzymes known to be responsible for DNA replication and repair in prokaryotes are DNA
polymerases I, II and IV.
Part C: Knowledge & Understanding-Matching (3 marks)
Match each item with the correct word or statement below. Indicate your selection
on the quiz below.
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
DNA polymerase I
Helicase
DNA polymerase III
Gyrase
Lagging strand
Template strand
Leading strand
Single-stranded binding proteins
Okazaki fragment
Replication fork
____ 25. Removes RNA primers
____ 26. New DNA strand synthesized in fragments
____ 27. Responsible for building new DNA strands during replication
____ 28. New DNA strand that is synthesized continuously
____ 29. Relieves tension in DNA during unwinding
____ 30. DNA strand that directs synthesis of a complementary strand
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Part D: Thinking & Investigation-Short Answer (8 marks)
31. Bearing in mind the different number of hydrogen bonds that form between the two different purinepyrimidine pairs in DNA, how would you explain the fact that DNA that is rich in cytosine-guanine
pairs requires heating to a slightly higher temperature in order to separate the strands than DNA
that is rich in adenine-thymine pairs? (1)
32. Two requirements for the type of molecule responsible for encoding hereditary information are the
following:
1. It must be capable of storing very large amounts of information.
2. It must lend itself to easy replication.
In the first half of the 20th century, it was considered that the hereditary material might be either
protein or DNA. One of the above requirements is satisfied by both of these types of molecules. In the
case of the other requirement, it is obvious that it is satisfied by one of the two candidate molecules, but
not so clear that it is satisfied by the other type. Which is the requirement satisfied by both protein and
DNA, and which is the requirement satisfied by only one of these? Explain your reasoning. (2)
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33. Imagine that you are a geneticist and are investigating a species of bacteriophage about which little is
known. How might Hershey and Chase's experiment be modified to discover whether the nucleic acid
in the bacteriophage is DNA or RNA? (2)
34. The nucleic acid from a particular species of bacteriophage is analyzed and found to have the
following percent composition:
adenine
33%
thymine
25%
cytosine
28%
guanine
14%
Examining this data, what conclusions can you make with respect to the structure of this nucleic acid?
[Describe the type of nucleic acid (DNA or RNA) and how many strands it contains]. (2)
35. Cancer often involves excessive and uncontrolled mitosis, resulting in a tumour. Some of the
chemotherapeutic agents used in cancer therapy inhibit/hinder DNA replication. While this can be an
effective treatment to stop tumour growth, it can have a negative effect on non-cancerous cells.
What is the main negative side effect of this treatment on non-cancerous cells/tissues? (1)
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