microbiology chapter 7
1. If a strand of mRNA is being copied by more than one ribosome at a time it forms a(n)
b. polysome
2. Genetic engineering
e. all of the above
3. A type of control mechanism where the product produced in the
pathway inhibits its own
production at the enzyme level is called
e. negative feedback inhibition
4. If the sequence of ATCGCACCT is copied from DNA to DNA what would the sequence be?
a. TAGCGTGGA
5. A set of genes under the control of the same regulatory elements defines a(n)
c. operon
6. The process where genetic information is carried to a new cell via a bacteriophage is
e. transduction
7. Which of the following is not true of bacterial DNA replication?
d. occurs within the membrane-bound nucleus
8. The cell component that processes the information on mRNA is the
b. ribosome
9. A self-replicating piece of extrachromosomal DNA defines a
d. plasmid
10. The process where DNA molecules are copied to RNA is
d. transcription
11. Damaged DNA can be repaired by
d. all of these
12. A term meaning genetic change is
d. mutation
13. Plasmids
e. all of the above
14. DNA polymerase reads DNA
b. in a 3' to 5' direction only
15. Mutations
e. all of the above
16. Resistance genes located on transposons
e. all of these
17. The nucleotides of RNA are
c. A,U,G,C
18. Mutations can occur
e. all of the above
19. In repressible operons
b. the substrate and the repressor molecule combine and prevent
transcription or
production of the product thus causing the
operon to normally be ON
20. In DNA replication, the enzyme that is used to unwind the helix is
b. Helicase
21. The enzyme that copies DNA is called
a. DNA Polymerase 3
22. An enzyme that is only produced when its substrate is present is a/an
b. inducible enzyme
23. The ability of living bacterial cells to incorporate DNA
fragments from outside the cell into their
own genome is
a. transformation
24. The process where the information on mRNA is used to synthesize protein is
b. translation
25. What would be the mRNA complementary sequence for the following
DNA sequence?
AATTAGGCC
a. UUAAUCCGG
26. The anti-codon is found on the
d. tRNA
27. In a DNA molecule, opposite strands are
b. complements of one another and are antiparallel
28. The transfer of DNA by direct contact between cells is
b. conjugation
29. In bacteria, RNA synthesis is initiated at specific sites called
c. promoters
30. Which of the following is not true of transposons?
a. are self-replicating
31. Transduction occurs when
b. when the phage genome is incorporated into the host genome
32. A phage often establishes a state of ______ in which a portion of
the viral nucleic acid is
incorporated into the bacterial
chromosome or a bacterial plasmid.
a. lysogeny
33. Viruses that transform cells and cause cancerous growth are called __________.
b. oncogenic viruses
34. Pallindromes are
a. repreated inverted DNA sequences within a chromosome or plasmid.
35. Transcription begins at a site called
b. promoter
36. If nucleotides are added/inserted into an organisms’s DNA sequence,
c. a frame shite mutation has occured
37. Match the following: DNA strand configuration
c. anti-parallel
38. Match the following: site where RNA synthesis begins on DNA
d. promoter
39. Transfer of DNA by competent cells
a. Transformation
40. Match the following: a gene which is continually expressed
e. constitutive
41. Match the following: Discontinuous replication
b. Okasaki fragments
42. Match the following: enzyme that joins DNA fragments during replication
c. Ligase
43. Match the following: RNA that contains information for more than one protein
d. polycistronic
44. Match the following: Enzyme that copies during DNA replication
b. DNA Polymerase III
45. Match the following: Transfer of genetic material via a virus
a. transduction
46. Match the following: Jumping genes
c. transposons
47. Match the following: requires binding site called pallindromes
b. insertion sequences
48. Match the following: insertion or deletion of DNA base
a. frame shift mutation
49. Match the following: Self-replicating extra-chromosomal DNA
d. plasmid
50. Match the following: Tranfer of genetic material via a sex pilus
e. conjugation
51. Match the following: genetic material that may act as a promoter
b. insertion sequences
52. Match the following: genetic material that may move from plasmid to chromosome
c. transposons
53. Eukaryotic chromosomes differ from prokaryotic chromosomes because only eukaryotes have
e. All of the choices are correct.
54. The DNA of microorganisms is made up of subunits called
c. nucleotides.
55. Which is incorrect about purines?
a. only found in DNA, not in RNA
56. The antiparallel arrangement within DNA molecules refers to
c. one helix strand that runs from the 5' to 3' direction and the
other strand runs from the
3' to 5' direction.
57. Semiconservative replication refers to
d. an original parent DNA strand and one newly synthesized DNA strand
comprising a
new DNA molecule
58. The duplication of a cell's DNA is called
b. replication.
59. DNA polymerase III
b. synthesizes new DNA only in the 5' to 3' direction.
60. Which enzyme fills in the spaces between the Okazaki fragments
with the correct
nucleotides?
a. DNA ligases
61. The enzymes that help pack DNA into the cell by coiling the DNA into a tight bundle are
d. DNA gyrases.
62. The enzymes that can proofread replicating DNA, detect incorrect
bases, excise them, and
correctly replace them are
b. DNA polymerases
63. The site where the old DNA strands separate and new DNA strands
will be synthesized is
called the
e. replication fork
64. Which enzyme is mismatched with its function in DNA replication?
RNA polymerase - synthesizes RNA primers
65. Groups of three consecutive bases along the DNA of a gene have the code for one
c. amino acid.
66. RNA molecules differ from DNA molecules because only RNA
e. All of the choices are correct.
67. All of the following pertain to transcription except it
a. occurs on a ribosome in the cytoplasm.
68. Which of the following is incorrect about transfer RNA?
e. the initiator tRNA in bacteria carries tryptophan
69. If a codon for alanine is GCA, then the anticodon is
d. CGU.
70. A sequence of bases on a gene that does not code for protein is called a/an
e. intron.
71. The following pertain to ribosomes during protein synthesis except they
a. contain codons within their rRNA molecules.
72. Which is incorrect about inducible operons?
a. they have genes turned off by a buildup of end product
73. The operon segment composed of the gene that codes for a protein repressor is called the
c. regulator.
74. Synthesis of an inducible enzyme requires
b. substrate bound to repressor.
75. Much of what was previously thought to be "junk" DNA
has been found to have which
purpose?
c. It codes for RNA regulatory molecules.
76. A mutation that changes a normal codon to a stop codon is called a
e. nonsense mutation.
77. The development of virulent, toxin-producing bacterial strains
due to the presence of a
temperate phage can occur in
d. specialized transduction.
78. Which is incorrect about pyrimidines?
a. are only found in DNA, not in RNA
79. The Ames test is designed to
e. detect chemicals with carcinogenic potential.
80. Individuals with xeroderma pigmentosa lack a functioning
a. photolyase.
81. All of the following are products of transcription except
c. DNA.
82. All of the following are true about mutations except
a. they are always detrimental to the organism they occur in.