Mutation, repair, and recombination

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Transcript Mutation, repair, and recombination

Chapter 16 Mutation, Repair and
Recombination
Question
Lysine and arginine are two amino acids with similar sized “R” (side-)
groups and similar biochemical behavior (for example, both are basic
residues). A mutation results in substitution of lysine for arginine and has
no detectable effect on the function of that protein. Which statement
best applies to this situation?
•The mutation is a silent mutation.
•The mutation is a frameshift mutation.
•The amino acid change is conservative.
•The amino acid change is silent.
•This organism displays no codon bias.
Question
Which of the following represents a correct or
acceptable phrase in genetics?
• Mutant protein
• Protein mutation
• DNA mutation
• A and C
• All of the above
Question
Which of the following statements is correct about the bases in
DNA under normal circumstances:
• Adenine should pair with thymine.
• The bonds holding guanine and cytosine together are
stronger than the bonds holding adenine and thymine
together.
• A purine always binds to a pyrimidine.
• A substitution of adenine for guanine is a transition mutation.
• All of the above
Carcinogens
and the Ames Test
Repair mechanisms
Photo reactivation repair
Base excision repair
Nucleotide excision repair
Transcription coupled repair
Mismatch repair
Undamaged DNA
UV light (mutagenic
agent)
EMS, NG (mutagenic
agent)
Pyrimidine dimers
Methylated base
Visible light
Alkyl
Transferase
Photolyase
Original Base
Inactivated
after action
Replication dependent repair
Question
Which of the following repair pathways do not
involve the use of a homology-dependent repair
system?
a. Base excision repair
b. Photo reactivation repair
c. Transcription coupled repair
d. Nucleotide excision repair
e. Mismatch repair
Question
•Which of the following DNA duplexes is most
stable?
5’ AATTAATTAATTAATTAATT 3’
3’ TTAATTAATTAATTAATTAA 5’
5’ GGCCGGCCGGCCGGCCGGCC 3’
3’ CCGGCCGGCCGGCCGGCCGG 5’
1. Both are equally stable.
2. B is more stable than A.
Question
Which of the following repair pathways do not
involve the use of a homology-dependent repair
system?
a. Base excision repair
b. Photo reactivation repair
c. Transcription coupled repair
d. Nucleotide excision repair
e. Mismatch repair