Transcription and Regulation MCQs : This section focuses on the "Transcription and Regulation". These Multiple Choice Questions (MCQs) should be practiced to improve the Transcription and Regulation skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
Question 1
Transcription of each set of rRNA genes by RNA polymerasel produces
A. a single 45S rRNA precursor molecule
B. a single 5S rRNA precursor molecule
C. a single 18S rRNA precursor molecule
D. a single 28S rRNA precursor molecule
Question 2
What is a promoter?
A. A specific sequence of DNA to which a catabolic repressor binds
B. A specific sequence of DNA to which RNA polymerase binds
C. A specific DNA sequence to which a restriction endonuclease binds
D. None of the above
Question 3
The complex of RNA polymerase, DNA template and new RNA transcript is called
A. transcription bubble
B. replication bubble
C. a translation bubble
D. none of these
Question 4
Enhancers are regions that
A. bind RNA polymerase
B. are adjacent to the TATA box
C. are CAT box binding proteins
D. modulate transcription
Question 5
Multiple copies of 5S genes, located at a chromosomal site distinct from the other rRNA genes
A. are transcribed by rRNA polymerase III and the 5S rRNA
B. are transcribed by rRNA polymerase II
C. are transcribed by rRNA polymerase I and the 5S rRNA
D. are transcribed by DNA polymerase I
Question 6
The function of the sigma factor of RNA polymerase is to
A. assure that transcription begins at the proper point
B. assure that transcription ends at the proper point
C. assure that translation begins at the proper point
D. assure that translation ends at the proper point
Question 7
The transcriptional regulatory proteins in eukaryotes which induce transcription usually have
A. at least two distinct domains of protein structure, a DNA binding domain and an activation domain
B. at least two distinct domains of protein structure and a DNA binding domain
C. at least one distinct domains of protein structure, a DNA binding domain and an activation domain
D. none of these
Question 8
Most transcripts of protein coding genes are cleaved
A. at the 3' end just after a poly adenylation signal
B. at the 3' end just before a poly adenylation signal
C. at the 5' end immediately after a poly adenylation signal
D. at the 5' end immediately before a poly adenylation signal
Question 9
RNA polymerase in prokaryotes has a removable
A. alpha subunit
B. beta subunit
C. both (a) and (b)
D. sigma subunit
Question 10
Promoters for tRNAs are located
A. upstream from the start codon
B. downstream from the start codon
C. both (a) and (b)
D. none of these
Question 11
Rho-dependent termination of transcription in E. coli
A. requires ATP
B. requires about 50 nucleotides of uncomplexed mRNA
C. both (a) and (b)
D. removes mRNA and holoenzyme from the DNA
Question 12
Immediately after transcription
A. a methylated guanine cap is added to the 51 end of the transcript
B. a methylated guanine cap is added to the 31 end of the transcript
C. both (a) and (b)
D. a poly adenylation signal is added
Question 13
The closed complex at bacterial promoters is
A. in equilibrium with free RNA polymerase and the promoter
B. not affected by promoter mutations
C. bound more tightly when repressors are present
D. not affected by activator proteins
Question 14
Transcription results in
A. an amino acid chain
B. messenger RNA
C. complementary DNA
D. Okazaki fragments
Question 15
Which of the following is necessary for transcription to occur?
A. DNA molecule
B. RNA polymerase
C. DNA polymerase
D. Both DNA & RNA polymerase
Question 16
Transcription begins
A. at the start codon
B. upstream from the start codon
C. downstream from the start codon
D. none of these
Question 17
Each tRNA molecule has a cloverleaf secondary structure consisting of
A. three stem loops
B. two stem loops
C. four stem loops
D. either (a) or (b)
Question 18
The RNA polymerases that transcribe bacterial DNA are
A. multisubunit enzymes
B. only active inside the cell
C. interchangable with DNA polymerases
D. highly glycosylated in their active forms
Question 19
Which of the following conditions would cause the release of the lac repressor protein from the lac operator site on DNA?
A. Presence of glucose in the growth media
B. Presence of lactose in the growth media
C. Presence of IPTG (isopropyl thiogalactoside) in the growth media
D. Both (b) and (c)
Question 20
Upstream regions which are essential for correct transcription are called
A. enhancers
B. start codons
C. promoters
D. transcription factors
Question 21
RNA polymerase holoenzyme initiates transcription which involves
A. recognition of the -10 sequence and -35 sequence
B. recognition of the -10 sequence only
C. recognition of the -35 sequence only
D. none of the above
Question 22
The major function of RNA polymerase's sigma factor is
A. recognition of the translational stop sequence
B. recognition of the transcriptional start sequence
C. recognition of the transcriptional stop sequence
D. recognition of the translational start sequence
Question 23
In eukaryotes, there are three different RNA polymerases. The RNA polymerase responsible for transcription of mRNA is
A. RNA polymerase I
B. RNA polymerase II
C. RNA polymerase III
D. none of these
Question 24
The nucleons of eukaryotic cell has
A. RNA polymerase I
B. RNA polymerase II
C. RNA polymerase III
D. all of these
Question 25
The regions of a gene located at -10 and -35, with respect to the start of transcription, are termed
A. start codons.
B. oriC regions.
C. Shine Dalgarno sequences.
D. promoters.
Question 26
In both eukaryotes and prokaryotes, a promoter region that is rich in AT bases is called as
A. CATT
B. Shine Dalgarno region
C. TATA box
D. SV40 region
Question 27
Transcription factors are
A. promoters
B. proteins which bind to DNA and regulate transcription
C. TATA boxes
D. CATT boxes
Question 28
In prokaryotes, transcription is
A. terminated by the stop codon
B. terminated by a protein called rho
C. terminated by a poly A sequence
D. terminated by a start codon
Question 29
RNA is synthesized on a DNA template in a process called __________ , which utilizes the enzyme __________
A. translation, RNA polymerase
B. transcription, DNA polymerase
C. transcription, RNA polymerase
D. replication, DNA polymerase
Question 30
Transcription by E. coli polymerase occurs in
A. four phases known as initiation, propagation, elongation and termination
B. three phases known as initiation, elongation and termination
C. two phases known as initiation and termination
D. none of the above
Question 31
The binding of lac repressor to DNA could be considered to be analogous to
A. competitive inhibition of an enzyme
B. mixed-type inhibition of an enzyme
C. uncompetitive inhibition of an enzyme
D. allosteric effects in enzyme regulation