REEF Question
• Which class of point mutation will almost always
result in a severely mutated amino acid sequence that
is functionally inadequate?
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A. frameshift
B. missense
C. neutral
D. silent
E. transition
REEF Question
• A normal 90 bp length of DNA gives rise to a 30 amino acid polypeptide after
transcription and translation. An AG mutation occurs in the DNA and the same
length of DNA. It now gives rise to a 19 amino acid polypeptide. Which of the
following is a viable explanation of the mutation’s impact
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A. It was a missense mutation.
B. The mutation changed a normal codon into a premature stop codon.
C. It was a silent mutation.
D. The mutation altered the ribosome.
E. The mutation changed a splice site, removing an intron from the sequence.
REEF Question
• A patient has a mutation in his mismatch repair system.
Experiments indicate that damage to the DNA is simply not
recognized by the system. Which gene in the mismatch repair
system is likely damaged?
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A. photolyase
B. translesion synthase
C. MutS homolog
D. MutL homolog
E. exonuclease
REEF Question
• Regions with thymine dimers are more likely to have
mutations because:
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A. repairs are impossible.
B. translesion polymerases cannot proofread.
C. translesion polymerases only insert guanines.
D. in a world where Justin Beiber exists, we have to expect bad things.
E. MutH cannot cut the proper strand.
REEF Question
• Glycosylase and AP endonuclease:
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A. are both involved in base excision repair.
B. work together to remove entire modified nucleotides
C. are both involved in nucleotide excision repair
D. A & B
E. B & C
REEF Question
• Which chromosomal abnormality will result in meiotic
synapsis that looks like this?
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A. partial chromosome deletion
B. paracentric inversion
C. pericentric inversion
D. reciprocal translocation
REEF Question
• An acentric chromosome fragment is produced during
recombination between a _____ and normal homolog.
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A. partial chromosome deletion
B. paracentric inversion
C. pericentric inversion
D. reciprocal translocation
REEF Question
• Which of the following conditions will result in the greatest
levels of transcription of the lac operon?
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A. lactose present, cAMP and glucose absent
B. lactose and cAMP present, glucose absent
C. lactose and glucose present, cAMP absent
D. lactose, glucose and cAMP present
REEF Question
• Mutations in the sequences of the 3-4 hairpin region of the
trp operon cause it to not form a secondary structure. What
will be the most obvious impact?
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A. constitutive expression of the trp operon products
B. no expression of the trp operon products
C. the activator will be permanently bound
D. lactose will be metabolized