BIOL133 COMPREHENSIVE EXAM STUDY
GUIDE COMPLETE QUESTIONS AND
SOLUTIONS
●● (16) A gene is made up of three exons (numbered consecutively)
with two introns (intron 1 between exons 1 and 2 and intron 2 between
exons 2 and 3). What would happen if there were a mutation at the 3'
splice site of intron 1?
Answer: mRNA with all three exons along with intron 1.
●● (16) If every cell in the body gets the same DNA, how do the cells of
an embryo make different structures and take on different roles? (Select
all that apply.)
Answer: A. Different transcription factors are active in different cells.
C. Genes are spliced differently in different cells.
D. Translation is regulated so that different cells may make more of
certain proteins.
●● (16) In eukaryotes, where would a protective modification be found
on mRNA?
Answer: On both the 5' end and the 3' end.
●● (16) _________ is the first protein to bind to mRNA to being
initiation of translation.
, Answer: eIF-2
●● (16) Epigenetics refers to a special kind of hereditary mechanism.
Epigenetic changes do not change the DNA nucleotide sequence, yet
their effect on gene expression can last for several generations.
In one surprising study, it was found that the grandsons of men who
suffered a famine were less likely to die of cardiovascular disease. The
experience of famine made some cardio-protective change in the sperm
of those grandfathers that was passed on.
What type of change was likely responsible?
Answer: Histone acetylation or DNA methylation.
●● (16) Enhancers located hundreds of bases upstream of a gene can be
brought to the promoter by _________.
Answer: DNA bending proteins.
●● (16) Overexpression of miRNAs can lead to a decrease of protein
expression associated with some forms of cancer. What could a drug do
to counter this effect?
Answer: Decrease expression of miRNA.
●● (16) What would happen if there were a mutation in the operator of
the trp operon?
Answer: The trp operon would continuously express the genes.
GUIDE COMPLETE QUESTIONS AND
SOLUTIONS
●● (16) A gene is made up of three exons (numbered consecutively)
with two introns (intron 1 between exons 1 and 2 and intron 2 between
exons 2 and 3). What would happen if there were a mutation at the 3'
splice site of intron 1?
Answer: mRNA with all three exons along with intron 1.
●● (16) If every cell in the body gets the same DNA, how do the cells of
an embryo make different structures and take on different roles? (Select
all that apply.)
Answer: A. Different transcription factors are active in different cells.
C. Genes are spliced differently in different cells.
D. Translation is regulated so that different cells may make more of
certain proteins.
●● (16) In eukaryotes, where would a protective modification be found
on mRNA?
Answer: On both the 5' end and the 3' end.
●● (16) _________ is the first protein to bind to mRNA to being
initiation of translation.
, Answer: eIF-2
●● (16) Epigenetics refers to a special kind of hereditary mechanism.
Epigenetic changes do not change the DNA nucleotide sequence, yet
their effect on gene expression can last for several generations.
In one surprising study, it was found that the grandsons of men who
suffered a famine were less likely to die of cardiovascular disease. The
experience of famine made some cardio-protective change in the sperm
of those grandfathers that was passed on.
What type of change was likely responsible?
Answer: Histone acetylation or DNA methylation.
●● (16) Enhancers located hundreds of bases upstream of a gene can be
brought to the promoter by _________.
Answer: DNA bending proteins.
●● (16) Overexpression of miRNAs can lead to a decrease of protein
expression associated with some forms of cancer. What could a drug do
to counter this effect?
Answer: Decrease expression of miRNA.
●● (16) What would happen if there were a mutation in the operator of
the trp operon?
Answer: The trp operon would continuously express the genes.
