BCMB 412 Exam 4 Questions With
What proteins are associated with the DNA polymerase III holoenzyme during
replication? - ANSWER DNA polymerase III, Tau proteins, and sliding clamp
loader
What proteins are associated with the replisome during replication? - ANSWER
SSB, DNA helicase, and primase
What are the initiator proteins that are loaded into replicators to initiate
replication in eukaryotes? - ANSWER The ORC complex
T/F: The RNA in telomerase serves as the primer for extending the 3'
overhanging ends of eukaryotic chromosomes. - ANSWER False
What factor of eukaryotic cells contributes to their ability to complete DNA
replication during the short window of time offered by the S phase? - ANSWER
Multiple origins of replication are activated per chromosome
What is the role of telomerase in eukaryotic cells? - ANSWER It synthesizes new
DNA using an RNA template at the DNA 3' ends of the chromosome
T/F: The MutS protein binds to mismatches generated during DNA replication,
initiating their repair, and is conserved from prokaryotes to eukaryotes. -
ANSWER True
What pathway removes uracil present in DNA? - ANSWER Base excision repair
How does base excision repair (BER) differ from nucleotide excision repair
(NER)? - ANSWER NER recognizes helix distortions while BER recognizes
specific base damage.
What is the role of MutS during the mismatch repair pathway? - ANSWER It
identifies mismatches
What is the role of MutH in the mismatch repair pathway? - ANSWER The
endonuclease cleaves the unmethylated strand
What is the role of MutL in the mismatch repair pathway? - ANSWER It bridges
two Mut proteins
, What is the role of UvrD in the mismatch repair pathway? - ANSWER The
helicase unpairs the DNA
What will a mutation in the sequence of prokaryotic DNA encoding the ribosome
binding site (RBS) result in? - ANSWER Reduced initiation of translation
What does an "aminoacyl-tRNA" refer to? - ANSWER Any tRNA covalently
attached to an amino acid at the 3' end of the tRNA
In prokaryotic translation initiation, which sequence serves as the recognition
site for the small ribosomal subunit? - ANSWER Shine-Dalgarno sequence
Which steps of prokaryotic translation do not require GTP hydrolysis? -
ANSWER Assembly of the 30S initiation complex
How can a premature stop codon be introduced into mRNA? - ANSWER Insertion
of an incorrect nucleotide by RNA polymerase during transcription, a mutation
in the coding sequence within the DNA, or a mistake during splicing that leads to
retention of an intron
Match the components involved in eukaryotic translation initiation:
a. Kozak sequence
b. eIF-4E
c. eIF-2
d. AUG codon - ANSWER a. Initiator sequence
b. Cap-binding protein
c. Initiator factor
d. Initiator tRNA
Match the elements involved in prokaryotic translation elongation:
a. Peptidyl transferase center
b. EF-Tu
c. EF-G - ANSWER a. peptide bond formation
b. delivers aminoacyl-tRNA to the A-site
c. translocates the ribosome along mRNA
T/F: An increase in transcription levels of genes encoding for ribosomal proteins
might not lead to a proportional increase in ribosomal protein levels. - ANSWER
True
What are the parts of a regulatory mechanism of global translation in eukaryotic
cells? - ANSWER Phosphorylation of eIF2, mTOR kinase activity, and
phosphorylation of eIF4E-BP
What proteins are associated with the DNA polymerase III holoenzyme during
replication? - ANSWER DNA polymerase III, Tau proteins, and sliding clamp
loader
What proteins are associated with the replisome during replication? - ANSWER
SSB, DNA helicase, and primase
What are the initiator proteins that are loaded into replicators to initiate
replication in eukaryotes? - ANSWER The ORC complex
T/F: The RNA in telomerase serves as the primer for extending the 3'
overhanging ends of eukaryotic chromosomes. - ANSWER False
What factor of eukaryotic cells contributes to their ability to complete DNA
replication during the short window of time offered by the S phase? - ANSWER
Multiple origins of replication are activated per chromosome
What is the role of telomerase in eukaryotic cells? - ANSWER It synthesizes new
DNA using an RNA template at the DNA 3' ends of the chromosome
T/F: The MutS protein binds to mismatches generated during DNA replication,
initiating their repair, and is conserved from prokaryotes to eukaryotes. -
ANSWER True
What pathway removes uracil present in DNA? - ANSWER Base excision repair
How does base excision repair (BER) differ from nucleotide excision repair
(NER)? - ANSWER NER recognizes helix distortions while BER recognizes
specific base damage.
What is the role of MutS during the mismatch repair pathway? - ANSWER It
identifies mismatches
What is the role of MutH in the mismatch repair pathway? - ANSWER The
endonuclease cleaves the unmethylated strand
What is the role of MutL in the mismatch repair pathway? - ANSWER It bridges
two Mut proteins
, What is the role of UvrD in the mismatch repair pathway? - ANSWER The
helicase unpairs the DNA
What will a mutation in the sequence of prokaryotic DNA encoding the ribosome
binding site (RBS) result in? - ANSWER Reduced initiation of translation
What does an "aminoacyl-tRNA" refer to? - ANSWER Any tRNA covalently
attached to an amino acid at the 3' end of the tRNA
In prokaryotic translation initiation, which sequence serves as the recognition
site for the small ribosomal subunit? - ANSWER Shine-Dalgarno sequence
Which steps of prokaryotic translation do not require GTP hydrolysis? -
ANSWER Assembly of the 30S initiation complex
How can a premature stop codon be introduced into mRNA? - ANSWER Insertion
of an incorrect nucleotide by RNA polymerase during transcription, a mutation
in the coding sequence within the DNA, or a mistake during splicing that leads to
retention of an intron
Match the components involved in eukaryotic translation initiation:
a. Kozak sequence
b. eIF-4E
c. eIF-2
d. AUG codon - ANSWER a. Initiator sequence
b. Cap-binding protein
c. Initiator factor
d. Initiator tRNA
Match the elements involved in prokaryotic translation elongation:
a. Peptidyl transferase center
b. EF-Tu
c. EF-G - ANSWER a. peptide bond formation
b. delivers aminoacyl-tRNA to the A-site
c. translocates the ribosome along mRNA
T/F: An increase in transcription levels of genes encoding for ribosomal proteins
might not lead to a proportional increase in ribosomal protein levels. - ANSWER
True
What are the parts of a regulatory mechanism of global translation in eukaryotic
cells? - ANSWER Phosphorylation of eIF2, mTOR kinase activity, and
phosphorylation of eIF4E-BP
