Exam 3; BIOL 4003 questions with
complete correct answers
Mutation in a sperm cell and a mutation that is passed from parent to offspring - ANS ✔✔Which
of the following is not an example of a somatic mutation?
- A mutation in an embryonic muscle cell
- A mutation in a sperm cell
- A mutation that is passed from parent to offspring
- Both B and C
Silent Mutation - ANS ✔✔A mutation changes a codon to another codon that does not change
the original amino acid to a different amino acid. This is a
Tautomeric shift that causes mis-base pairing - ANS ✔✔Which of the following is a cause of
spontaneous mutations?
- 5-bromouracil used for chemotherapy
- UV light
- A tautomeric shift that causes mis-base pairing
- A chemical such as nitrous acid that can change the structure of a base
They contain at least one C and one G - ANS ✔✔What is a key characteristic(s) of the repeat
sequences that promote trinucleotide repeat expansion?
The mutation is a translocation that moves the gene from a euchromatic region to a
heterochromatic region. - ANS ✔✔Which of the following is/are a possible reason why a
mutation may have a position effect?
- The mutation is located next to the gene's promoter.
, - The mutation is a translocation that moves the gene from a euchromatic region to a
heterochromatic region.
- The mutation alters the start codon.
- All of the above are mutations that can have a position effect.
more, his- to his+ - ANS ✔✔Let's suppose that a chemical is a mutagen. If you tested this
chemical using the Ames test, there will be_________ colonies on the plates in which the cells
had been exposed to the mutagen, because the mutagen converts some of the cells from
____________.
C, B, A, D - ANS ✔✔Below are 4 steps that occur in the nucleotide excision repair system. What
is their correct order?
A. Removal of the damaged region
B. Endonuclease cleavage on either side of the lesion
C. Sensing of a DNA lesion
D. Use of the opposite strand (without a lesion) as a template to make new DNA
Gap Repair Synthesis - ANS ✔✔A gene exists in two alleles, which we will call B and b. The gene
is 1123 bp in length, and the B and b alleles exhibit single base pair differences at six different
sites. If gene conversion changed the b allele into the B allele, which mechanism would you
favor to explain the conversion?
The formation of a D loop - ANS ✔✔According to the double-strand break model for
homologous recombination, what happens right after DNA strand degradation at the double-
stranded break site?
2 - ANS ✔✔According to the Holliday model for homologous recombination, how many DNA
strands are cut during the resolution step?
complete correct answers
Mutation in a sperm cell and a mutation that is passed from parent to offspring - ANS ✔✔Which
of the following is not an example of a somatic mutation?
- A mutation in an embryonic muscle cell
- A mutation in a sperm cell
- A mutation that is passed from parent to offspring
- Both B and C
Silent Mutation - ANS ✔✔A mutation changes a codon to another codon that does not change
the original amino acid to a different amino acid. This is a
Tautomeric shift that causes mis-base pairing - ANS ✔✔Which of the following is a cause of
spontaneous mutations?
- 5-bromouracil used for chemotherapy
- UV light
- A tautomeric shift that causes mis-base pairing
- A chemical such as nitrous acid that can change the structure of a base
They contain at least one C and one G - ANS ✔✔What is a key characteristic(s) of the repeat
sequences that promote trinucleotide repeat expansion?
The mutation is a translocation that moves the gene from a euchromatic region to a
heterochromatic region. - ANS ✔✔Which of the following is/are a possible reason why a
mutation may have a position effect?
- The mutation is located next to the gene's promoter.
, - The mutation is a translocation that moves the gene from a euchromatic region to a
heterochromatic region.
- The mutation alters the start codon.
- All of the above are mutations that can have a position effect.
more, his- to his+ - ANS ✔✔Let's suppose that a chemical is a mutagen. If you tested this
chemical using the Ames test, there will be_________ colonies on the plates in which the cells
had been exposed to the mutagen, because the mutagen converts some of the cells from
____________.
C, B, A, D - ANS ✔✔Below are 4 steps that occur in the nucleotide excision repair system. What
is their correct order?
A. Removal of the damaged region
B. Endonuclease cleavage on either side of the lesion
C. Sensing of a DNA lesion
D. Use of the opposite strand (without a lesion) as a template to make new DNA
Gap Repair Synthesis - ANS ✔✔A gene exists in two alleles, which we will call B and b. The gene
is 1123 bp in length, and the B and b alleles exhibit single base pair differences at six different
sites. If gene conversion changed the b allele into the B allele, which mechanism would you
favor to explain the conversion?
The formation of a D loop - ANS ✔✔According to the double-strand break model for
homologous recombination, what happens right after DNA strand degradation at the double-
stranded break site?
2 - ANS ✔✔According to the Holliday model for homologous recombination, how many DNA
strands are cut during the resolution step?
