BIO 172 EXAM 2 WITH 100%
CORRECT ANSWERS 2026
Which of the following would a regulatory transcription factor
most likely recruit to a silencer?
A. RNA polymerase
B. Basal transcription factors
C. HDACs
D. HATs correct answer C
Which of the following would a regulatory transcription factor
most likely recruit to an enhancer?
A. Basal transcription factors
B. HATs
C. HDACs
D. RNA polymerase correct answer B
,A transcription factor that binds to an enhancer might be
expected to recruit which of the following factor or factors?
A. A DNA methyltransferase or a histone acetyltransferase
B. Histone acetyltransferase
C. A DNA methyltransferase or a histone deacetylase
D. Histone deacetylase correct answer B
A histone acetylase might be recruited to a _____________, while a
histone deacetylase might be recruited to a ______________.
A. Operator, silencer
B. Enhancer, enhancer
C. Silencer, enhancer
D. Enhancer, silencer
E. Silencer, operator correct answer D
Which of the following statements about enhancers is correct?
,A. They are located only in introns
B. They bind to general transcription factors to recruit RNA
polymerase to the promoter
C. They are found in a variety of locations in the DNA and are
functional in any orientation
D. They contain a unique base sequence called the TATA box
correct answer C
Packaging of DNA into chromatin...
A. Is identical in different cells of the body
B. Has no effect on transcription
C. Promotes transcription by opening up chromatin
D. Inhibits transcription by blocking RNA Polymerase from
accessing DNA correct answer D
Histone modification:
A. can change over time in response to environmental cues,
allowing genes to be turned on or off as needed
, B. is fixed; once a histone is modified, it stays that way and the
genes with which it is associated are turned on or off permanently
C. can change over time in response to environmental cues, but
this has no effect on gene expression
D. is random; sometimes the lysines are modified and sometimes
they are not, but the state is independent of the environment or
cell type
E. is fixed, but this has no effect on whether genes are expressed
correct answer A
In eukaryotic cells, why are certain genes expressed only in
certain types of cells?
A. Different cell types have the same genes but different
promoters
B. Different cell types have different genes
C. Different cell types have different regulatory transcription
factors
D. Different cell types have different regulatory transcription
factors correct answer D
Histone acetyl transferases exert their effect on gene activity by
CORRECT ANSWERS 2026
Which of the following would a regulatory transcription factor
most likely recruit to a silencer?
A. RNA polymerase
B. Basal transcription factors
C. HDACs
D. HATs correct answer C
Which of the following would a regulatory transcription factor
most likely recruit to an enhancer?
A. Basal transcription factors
B. HATs
C. HDACs
D. RNA polymerase correct answer B
,A transcription factor that binds to an enhancer might be
expected to recruit which of the following factor or factors?
A. A DNA methyltransferase or a histone acetyltransferase
B. Histone acetyltransferase
C. A DNA methyltransferase or a histone deacetylase
D. Histone deacetylase correct answer B
A histone acetylase might be recruited to a _____________, while a
histone deacetylase might be recruited to a ______________.
A. Operator, silencer
B. Enhancer, enhancer
C. Silencer, enhancer
D. Enhancer, silencer
E. Silencer, operator correct answer D
Which of the following statements about enhancers is correct?
,A. They are located only in introns
B. They bind to general transcription factors to recruit RNA
polymerase to the promoter
C. They are found in a variety of locations in the DNA and are
functional in any orientation
D. They contain a unique base sequence called the TATA box
correct answer C
Packaging of DNA into chromatin...
A. Is identical in different cells of the body
B. Has no effect on transcription
C. Promotes transcription by opening up chromatin
D. Inhibits transcription by blocking RNA Polymerase from
accessing DNA correct answer D
Histone modification:
A. can change over time in response to environmental cues,
allowing genes to be turned on or off as needed
, B. is fixed; once a histone is modified, it stays that way and the
genes with which it is associated are turned on or off permanently
C. can change over time in response to environmental cues, but
this has no effect on gene expression
D. is random; sometimes the lysines are modified and sometimes
they are not, but the state is independent of the environment or
cell type
E. is fixed, but this has no effect on whether genes are expressed
correct answer A
In eukaryotic cells, why are certain genes expressed only in
certain types of cells?
A. Different cell types have the same genes but different
promoters
B. Different cell types have different genes
C. Different cell types have different regulatory transcription
factors
D. Different cell types have different regulatory transcription
factors correct answer D
Histone acetyl transferases exert their effect on gene activity by
