BIOL 2321 Exam 3 Test Questions AND
ANSWERS
The process of transcription and translation is carried out in a test tube. To a test tube is
added:
A. from a hippo: mRNA, tRNA's, ribosomes
B. from a fish: DNA
C. from a zebra: RNA polymerase + other necessary enzymes; ribonucleotides & amino
acids
Assume some NEW protein is made in the test tube. The proteins of which animal(s)
will be expressed?
A. Hippo only
B. Fish only
C. Zebra only
D. Hippo & Fish
E. Hippo & Zebra
F. Fish & Zebra - Correct Answers -D. Hippo & Fish
Which of these terms includes ALL of the others?
A. Regulon
B. Gene
C. Transcriptome
D. Genome
E. Operon
F. Proteome - Correct Answers -D. Genome
Which is true regarding bacterial operons and gene expression?
A. The operator serves as the site for sigma factor binding.
B. An operon possesses multiple promoters.
C. The structural genes of a single operon code for enzymes of differing metabolic
pathways.
D. A single operon transcript will contain information for all of the structural genes of that
operon.
E. Regulon = regulatory gene + the regulatory protein
F. NONE of A‐E are true. - Correct Answers -D. A single operon transcript will contain
information for all of the structural genes of that operon.
, Transformation requires
A. cell to cell contact.
B. a viral intermediate.
C. a sex pilus.
D. a plasmid.
E. DNA fragments in the environment.
F. A transposase. - Correct Answers -E. DNA fragments in the environment.
Formation of an Hfr cell requires
A. a viral intermediate.
B. a sex pilus.
C. an F factor integrated in the chromosome
D. an F- cell
E. DNA fragments in the environment
F. a sigma factor - Correct Answers -C. an F factor integrated in the chromosome
Formation of an F' (prime) factor requires
A. DNA fragments in the environment
B. a transposase.
C. an Hfr cell.
D. an F- cell
E. excision of DNA from the chromosome
F. lambda phage
G. two of the above - Correct Answers -G. two of the above (C & E)
Tryptophan operon expression can be controlled by tryptophan itself inhibiting one of
the enzymes responsible for its synthesis. This is an example of
A. Control at the level of DNA (altering nucleotides)
B. Post‐translational control
C. Transcriptional control
D. Translational control - Correct Answers -B. Post‐translational control
An active repressor
A. promotes transcription
B. requires an inducer
C. allows RNA polymerase to carry out its function
D. is in a de‐repressed state
E. binds to an operator
F. none of the above - Correct Answers -E. binds to an operator
Which is true among A‐D regarding the lac operon?
ANSWERS
The process of transcription and translation is carried out in a test tube. To a test tube is
added:
A. from a hippo: mRNA, tRNA's, ribosomes
B. from a fish: DNA
C. from a zebra: RNA polymerase + other necessary enzymes; ribonucleotides & amino
acids
Assume some NEW protein is made in the test tube. The proteins of which animal(s)
will be expressed?
A. Hippo only
B. Fish only
C. Zebra only
D. Hippo & Fish
E. Hippo & Zebra
F. Fish & Zebra - Correct Answers -D. Hippo & Fish
Which of these terms includes ALL of the others?
A. Regulon
B. Gene
C. Transcriptome
D. Genome
E. Operon
F. Proteome - Correct Answers -D. Genome
Which is true regarding bacterial operons and gene expression?
A. The operator serves as the site for sigma factor binding.
B. An operon possesses multiple promoters.
C. The structural genes of a single operon code for enzymes of differing metabolic
pathways.
D. A single operon transcript will contain information for all of the structural genes of that
operon.
E. Regulon = regulatory gene + the regulatory protein
F. NONE of A‐E are true. - Correct Answers -D. A single operon transcript will contain
information for all of the structural genes of that operon.
, Transformation requires
A. cell to cell contact.
B. a viral intermediate.
C. a sex pilus.
D. a plasmid.
E. DNA fragments in the environment.
F. A transposase. - Correct Answers -E. DNA fragments in the environment.
Formation of an Hfr cell requires
A. a viral intermediate.
B. a sex pilus.
C. an F factor integrated in the chromosome
D. an F- cell
E. DNA fragments in the environment
F. a sigma factor - Correct Answers -C. an F factor integrated in the chromosome
Formation of an F' (prime) factor requires
A. DNA fragments in the environment
B. a transposase.
C. an Hfr cell.
D. an F- cell
E. excision of DNA from the chromosome
F. lambda phage
G. two of the above - Correct Answers -G. two of the above (C & E)
Tryptophan operon expression can be controlled by tryptophan itself inhibiting one of
the enzymes responsible for its synthesis. This is an example of
A. Control at the level of DNA (altering nucleotides)
B. Post‐translational control
C. Transcriptional control
D. Translational control - Correct Answers -B. Post‐translational control
An active repressor
A. promotes transcription
B. requires an inducer
C. allows RNA polymerase to carry out its function
D. is in a de‐repressed state
E. binds to an operator
F. none of the above - Correct Answers -E. binds to an operator
Which is true among A‐D regarding the lac operon?
