GCU BIO 181 Final Exam with All Correct & 100%
Verified Answers |Latest Update |Already Graded A+
The tryptophan operon is a repressible operon that is: ✔Correct Answer--Turned off whenever
tryptophan is added to the growth medium.
The lactose operon is likely to be transcribed when: ✔Correct Answer--The cyclic AMP and lactose
levels are both high within the cell.
For a repressible operon to be transcribed, which of the following must occur? ✔Correct Answer--
RNA polymerase must bind to the promoter, and the repressor must be inactive.
Which of the following, when taken up by the cell, binds to the repressor so that the repressor no
longer binds to the operator? ✔Correct Answer--Inducer
What is a promoter? ✔Correct Answer--Sequence where the RNA polymerase binds and begins
transcription. It is upstream of the sequence encoding the protein
Which of the following is a protein produced by a regulatory gene? ✔Correct Answer--Repressor
What is a corepressor? ✔Correct Answer--A small molecule that combines with and activates a
repressor produced by a regular gene
What is an operator? ✔Correct Answer--A regulatory sequence that a repressor can bind to
What is a regulatory gene? ✔Correct Answer--Genes that encode a protein involved in regulation
of gene expression
What has to happen for a gene to be transcribed? ✔Correct Answer--RNA polymerase, which
makes new RNA molecules from a DNA template, must attach to the DNA of the gene.
In eukaryotes, general transcription factors: ✔Correct Answer--Bind to other proteins or to a
sequence element within the promoter called the TATA box.
What is a TATA box? ✔Correct Answer--DNA sequence that indicates where a genetic sequence can
be read and decoded
Two potential devices that eukaryotic cells use to regulate transcription are ✔Correct Answer--DNA
methylation and histone modification. (epigenetic phenomena)
Why are viruses obligate parasites? ✔Correct Answer--They cannot reproduce outside of the host
cell
Which characteristic is common to all viruses? ✔Correct Answer--A genome (nucleic acid) enclosed
in a protein capsid
All viruses contain what? ✔Correct Answer--A genome and a protein capsid
, What determines the host range of a virus? ✔Correct Answer--The receptor protein that is on the
cell surface
Virulent envelope is made of molecules called? ✔Correct Answer--Viral glycoproteins that help
with attachment to the surface of animal viruses, which are proteins plus carbohydrates
Virulent phages undergo what? ✔Correct Answer--Lytic life cycle
Temperature changes are capable of undergoing what? ✔Correct Answer--Lytic and lysogenic
cycles
What is the Lytic cycle? ✔Correct Answer--A large number of phages are released at a time. Results
in the death of the host cell
What is the lysogenic cycle? ✔Correct Answer--Replicates the phage genome without destroying
the host. The viral DNA molecule is incorporated into the host cell's chromosome. The integrated
viral DNA is known as a prophage. Every time the host divides, the phage genome replicates along
with the host genome.
What is a bacteriophage? ✔Correct Answer--Viruses that infect bacteria
RNA viruses replication- does not involve the proofreading steps of DNA replication
How do prokaryotes reproduce? ✔Correct Answer--They reproduce by binary fission
What is transformation? ✔Correct Answer--The process in which external DNa form the
surrounding environment is taken up by a prokaryotic cell.
What is transduction? ✔Correct Answer--The movement of genes between bacteria by
bacteriophages
What is conjugation? ✔Correct Answer--The process where DNA is exchanged between bacterial
cells through sex pilus
When does tryptophan operon turned off? ✔Correct Answer--Turned off when tryptophan is
added to growth medium
What is the lactose operon? ✔Correct Answer--Inducible operon. Turned on when lactose levels
are high within the cell
What does the the inducer do to the repressor? ✔Correct Answer--Binds to the repressor so that
the repressor cannot bind to the operator
What is a regulatory gene code for? ✔Correct Answer--Codes for the repressor protein
What does a corepressor do? ✔Correct Answer--Binds to the repressor
What does RNA polymerase do? ✔Correct Answer--Binds to the promoter and transcribes
structural genes.
What is a repressible operon ✔Correct Answer--Tryptophane. Always turned on
Verified Answers |Latest Update |Already Graded A+
The tryptophan operon is a repressible operon that is: ✔Correct Answer--Turned off whenever
tryptophan is added to the growth medium.
The lactose operon is likely to be transcribed when: ✔Correct Answer--The cyclic AMP and lactose
levels are both high within the cell.
For a repressible operon to be transcribed, which of the following must occur? ✔Correct Answer--
RNA polymerase must bind to the promoter, and the repressor must be inactive.
Which of the following, when taken up by the cell, binds to the repressor so that the repressor no
longer binds to the operator? ✔Correct Answer--Inducer
What is a promoter? ✔Correct Answer--Sequence where the RNA polymerase binds and begins
transcription. It is upstream of the sequence encoding the protein
Which of the following is a protein produced by a regulatory gene? ✔Correct Answer--Repressor
What is a corepressor? ✔Correct Answer--A small molecule that combines with and activates a
repressor produced by a regular gene
What is an operator? ✔Correct Answer--A regulatory sequence that a repressor can bind to
What is a regulatory gene? ✔Correct Answer--Genes that encode a protein involved in regulation
of gene expression
What has to happen for a gene to be transcribed? ✔Correct Answer--RNA polymerase, which
makes new RNA molecules from a DNA template, must attach to the DNA of the gene.
In eukaryotes, general transcription factors: ✔Correct Answer--Bind to other proteins or to a
sequence element within the promoter called the TATA box.
What is a TATA box? ✔Correct Answer--DNA sequence that indicates where a genetic sequence can
be read and decoded
Two potential devices that eukaryotic cells use to regulate transcription are ✔Correct Answer--DNA
methylation and histone modification. (epigenetic phenomena)
Why are viruses obligate parasites? ✔Correct Answer--They cannot reproduce outside of the host
cell
Which characteristic is common to all viruses? ✔Correct Answer--A genome (nucleic acid) enclosed
in a protein capsid
All viruses contain what? ✔Correct Answer--A genome and a protein capsid
, What determines the host range of a virus? ✔Correct Answer--The receptor protein that is on the
cell surface
Virulent envelope is made of molecules called? ✔Correct Answer--Viral glycoproteins that help
with attachment to the surface of animal viruses, which are proteins plus carbohydrates
Virulent phages undergo what? ✔Correct Answer--Lytic life cycle
Temperature changes are capable of undergoing what? ✔Correct Answer--Lytic and lysogenic
cycles
What is the Lytic cycle? ✔Correct Answer--A large number of phages are released at a time. Results
in the death of the host cell
What is the lysogenic cycle? ✔Correct Answer--Replicates the phage genome without destroying
the host. The viral DNA molecule is incorporated into the host cell's chromosome. The integrated
viral DNA is known as a prophage. Every time the host divides, the phage genome replicates along
with the host genome.
What is a bacteriophage? ✔Correct Answer--Viruses that infect bacteria
RNA viruses replication- does not involve the proofreading steps of DNA replication
How do prokaryotes reproduce? ✔Correct Answer--They reproduce by binary fission
What is transformation? ✔Correct Answer--The process in which external DNa form the
surrounding environment is taken up by a prokaryotic cell.
What is transduction? ✔Correct Answer--The movement of genes between bacteria by
bacteriophages
What is conjugation? ✔Correct Answer--The process where DNA is exchanged between bacterial
cells through sex pilus
When does tryptophan operon turned off? ✔Correct Answer--Turned off when tryptophan is
added to growth medium
What is the lactose operon? ✔Correct Answer--Inducible operon. Turned on when lactose levels
are high within the cell
What does the the inducer do to the repressor? ✔Correct Answer--Binds to the repressor so that
the repressor cannot bind to the operator
What is a regulatory gene code for? ✔Correct Answer--Codes for the repressor protein
What does a corepressor do? ✔Correct Answer--Binds to the repressor
What does RNA polymerase do? ✔Correct Answer--Binds to the promoter and transcribes
structural genes.
What is a repressible operon ✔Correct Answer--Tryptophane. Always turned on
