Exam and Pretest Questions Flashcards
Which statement about DNA polymerase III is FALSE?
a. It is responsible for incorporating most of the nucleotides in the leading strand.
b. It contains a 3’ to 5’ proofreading activity.
c. It is responsible for incorporating most of the nucleotides in the lagging strand.
d. It does not require primers to extend the leading strand.
e. It has a very low error rate.
d. It does not require primers to extend the leading strand.
One function of DNA pol I during replication in prokaryotes is to:
a. join the ends of adjacent Okazaki fragments together
b. separate the double-stranded DNA into single-stranded regions
c. replicate the lagging strand of DNA in eukaryotic cells
d. relieve tension induced by supercoiling
e. remove the RNA primers that initiate replication
a. join the ends of adjacent Okazaki fragments together
The enzyme used in making cDNA is:
a. DNA ligase
b. a thermostable DNA polymerase
c. reverse transcriptase
d. polynucleotide kinase
e. the single-stranded binding protein PCNA
c. reverse transcriptase
7-methyl-guanosine is added to mRNA molecules during a processing reaction in eukaryotes. The unique processing event is a:
a. 3’-5’ triphosphate linkage at the 3’ end of the RNA
b. 2’-5’ triphosphate linkage at the 5’ end of the RNA
c. 3’-5’ triphosphate linkage at the 5’ end of the RNA
d. 3’-2’ triphosphate linkage at the 3’ end of the RNA
e. 5’-5’ triphosphate linkage at the 5’ end of the RNA
e. 5’-5’ triphosphate linkage at the 5’ end of the RNA
The reduced expression of the lac operon in the presence of glucose is an example of :
a. transcriptional activation
b. catabolite repression
c. operon silencing
d. regulatory dominance
e. anabolic repression
b. catabolite repression
Attenuation at the trp operon in E. coli occurs when:
a. translation and transcription become uncoupled
b. high tryptophan levels inhibit the binding of a repressor protein
c. low tryptophan levels increase the rate of RNA polymerase progression
d. high tryptophan levels allow the formation of a terminator stem-loop in the trpL mRNA
e. the tryptophan membrane transporter increases the rate of tryptophan import
d. high tryptophan levels allow the formation of a terminator stem-loop in the trpL mRNA
Which is most commonly found in the P site of ribosomes?
a. a tRNA with the growing peptide chain attached
b. a tRNA with no amino acid attached
c. a tRNA with a single amino acid attached
d. ribosome releasing factor
e. termination factor
a. a tRNA with the growing peptide chain attached
Which statement about the Shine-Delgarno sequence is FALSE?
a. it is found near the 5’ end of prokaryotic mRNAs.
b. it is complementary to a sequence near the 3’ end of the 16S rRNA.
c. it helps position the small ribosomal subunit near the translation start site.
d. it contains the AUG initiator codon.
e. it is required for efficient translation.
d. it contains the AUG initiator codon.
Which of the following methods would be used to determine the amino acid sequence of a peptide?
a. polymerase chain reaction
b. western blotting
c. organism cloning
d. gel shift assay
e. mass spectrometry
e. mass spectrometry
Mass spectrometry can detect all of these EXCEPT:
a. proteins that have been post-translationally modified.
b. proteins made from mRNAs that have been alternatively spliced.
c. proteins made from mRNAs that have used alternate polyadenylation sites.
d. proteins present in cancer cells but not in normal cells.
e. proteins that have been localized in the wrong cellular compartment.
e. proteins that have been localized in the wrong cellular compartment.
Which of the following types of mutation is likely to have the greatest consequence to the cell?
a. a G => A change that creates a stop codon within a gene
b. trisomy of an autosome
c. an insertion of a T in a homopolymeric run of Ts
d. an inversion of the long arm of the X chromosome
e. a reciprocal translocation between two autosomes
b. trisomy of an autosome
A scientist suspects that a short translocation has occurred that might involve a gene that she is studying. What is the fastest way to determine if the cells carry the translocation?
a. sequence the genome with DNA from the cells
b. use PCR to amplify the gene
c. use a labeled probe of the gene to do in situ hybridization
d. do a chromosome walk with the gene as an initial probe
e. construct a YAC library from the cell’s DNA
c. use a labeled probe of the gene to do in situ hybridization
Which statement about RNA interference is FALSE?
a. it occurs only in plants.
b. it involves short RNAs that are complementary to the target mRNA.
c. it can inhibit the transcription of the target mRNA.
d. it can cause the degradation of the target mRNA.
e. it can inhibit the translation of the target mRNA.
a. it occurs only in plants.
The function of helicases during replication is to join the ends of adjacent Okazaki fragments together
True or False?
False
The function of helicases during replication is to separate the DNA strands from each other.
True or False?
True!
The function of helicases during replication is to relieve tension induced by supercoiling.
True or False?
False
The function of helicases during replication is to remove the RNA primers that initiate replication.
True or False?
False
Microarrays are useful when studying the gene expression in cancer cells because they can identify all of the genes that are overexpressed.
True or False?
True
Microarrays are useful when studying the gene expression in cancer cells because they can identify all of the genes that are underexpressed.
True or False?
True
Microarrays are useful when studying the gene expression in cancer cells because they can identify all of the genes that have point mutations.
True or False?
False
The following DNA mutation is likely to result in a shorter than normal mRNA:
True / False
- A -> C at position 10
- G -> A at position 13
- C -> A at position 18
- False
- False
- False
The following DNA mutation is likely to result in a shorter than normal protein:
True / False
- T -> C at position 19
- A -> G at position 21
- insertion of a G after the G at position 14
- False
- False
- True
In partially diploid E. coli cells with the genotype F’ i+ o- z- y+ a-/ chromosome i- o+ z+ y- a+, which functional gene product(s) would be expressed at high level in the absence of lactose?
True / False
- β-galactosidase only
- β-galactosidase, permease, and transacetylase
- permease only
- permease and transacetylase
- False
- False
- True
- False
Which of the following statements about nucleotides are true and which are false?
True / False
- The phosphate group is attached to the nitrogenous base.
- A nucleotide contains a base, a sugar, and a phosphate group.
- The sugar contains two nitrogen atoms.
- The nitrogenous base is attached to the sugar by a glycosidic bond.
- False
- True
- False
- True
Histone acetyltransferases act to:
True / False
- eliminate the positive charge of lysines in histones
- increase the compaction of DNA around histones
- help the histones reassemble following DNA replication
- prevent the translation of histone mRNA molecules
- remove covalent modifications on the lysine residues of histones
- True
- False
- False
- False
- False
During protein synthesis, the tRNA synthetase acts to:
True / False
- attach an amino acid to the anticodon of the tRNA
- transcribe the genes encoding tRNAs to produce tRNA molecules
- serve as the first initiation factor during ribosome assembly
- covalently bind an amino acid to the acceptor stem of the tRNA
- cause precursor tRNA molecules to adopt their proper final structure
- False
- False
- False
- True
- False
The following are tRNA binding sites found within ribosomes:
True / False
- peptidyl site
- exit site
- elongation site
- aminoacyl site
- True
- True
- False
- True
For which of the following experiments would a DNA microarray be useful?
True / False
- identifying the binding site for a transcription factor
- determining which genes are induced when a chemical is added to a cell’s growth medium
- determining which genes are down-regulated in response to heat shock
- identifying the site of a DNA inversion
- distinguishing between two closely related bacterial subspecies
- True
- True
- True
- False
- True
In each blank, put the letter of the process that is most associated with the given phrase or word.
URE
a. DNA repair
b. DNA replication
c. RNA processing
d. transcription
e. translation
d. transcription
In each blank, put the letter of the process that is most associated with the given phrase or word.
Shine-Delgarno sequence
a. DNA repair
b. DNA replication
c. RNA processing
d. transcription
e. translation
e. translation
In each blank, put the letter of the process that is most associated with the given phrase or word.
tRNA
a. DNA repair
b. DNA replication
c. RNA processing
d. transcription
e. translation
e. translation
In each blank, put the letter of the process that is most associated with the given phrase or word.
non-template strand
a. DNA repair
b. DNA replication
c. RNA processing
d. transcription
e. translation
d. transcription
In each blank, put the letter of the process that is most associated with the given phrase or word.
AUG codon
a. DNA repair
b. DNA replication
c. RNA processing
d. transcription
e. translation
e. translation
In each blank, put the letter of the process that is most associated with the given phrase or word.
primase
a. DNA repair
b. DNA replication
c. RNA processing
d. transcription
e. translation
b. DNA replication
In each blank, put the letter of the process that is most associated with the given phrase or word.
TATA box
a. DNA repair
b. DNA replication
c. RNA processing
d. transcription
e. translation
d. transcription
In each blank, put the letter of the process that is most associated with the given phrase or word.
splicing
a. DNA repair
b. DNA replication
c. RNA processing
d. transcription
e. translation
c. RNA processing
In each blank, put the letter of the process that is most associated with the given phrase or word.
Pribnow box
a. DNA repair
b. DNA replication
c. RNA processing
d. transcription
e. translation
d. transcription
In each blank, put the letter of the process that is most associated with the given phrase or word.
hemi-methylated DNA
a. DNA repair
b. DNA replication
c. RNA processing
d. transcription
e. translation
a. DNA repair
In a gene, the DNA strand that has the same sequence of nucleotides as the mRNA transcribed from that gene is known as the strand.
non-template or sense or coding
The coding sequences in eukaryotic genes that are joined during pre m-RNA splicing are called .
exons.
Thymine crosslinked dimers in DNA are usually fixed by which repair mechanism?
Nucleotide excision repair
A Northern blot is used to detect what type of molecule?
RNA
What type of probe(s) is used in a Northern blot?
Nucleic acid: DNA, RNA, oligo, etc.
A Southern blot is used to detect what type of molecule?
DNA
What type of probe(s) is used in a Southern blot?
Nucleic acid: DNA, RNA, oligo, etc.