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1 - Automated sequencing is defined as _________
Real time fluorescence sequencing
2 - Automated sequencing uses _____________
Fluorescent tagging
3 - No chain termination takes place in automated sequencing.
FALSE
4 - As different fluorescent tags affect the mobility of fragments thus only one type of tag is used.
FALSE
5 - With respect to automated sequencing which of the following is true?
Horizontal scanning one sequence per lane
6 - Which of the following feature is required for the high sensitivity of the tags used for autosequencing?
Maximum emittion at different wavelengths
7 - Automated sequencing is a real time one trial method of sequencing and is highly handy.
FALSE
8 - A third generation sequencing can sequence upto ____________nucleotides per day.
750000
9 - During DNA cloning which of the following is not a crucial requirement?
Protein expression
10 - Transformation does not involve ____________
Expression
11 - Which is the most common organism considered for genetic manipulations?
E. coli
12 - Which of the following is an essential feature for being a perfect vector?
Virulent gene
13 - DNA ligase can ligate restriction site ends produced by EcoRI to the ends of DNA insert cut by the same enzyme.
TRUE
14 - The vector and the DNA insert are cut by different enzymes for convenience.
FALSE
15 - What is the major difference between cloning vectors and primary vectors?
Presence of promoter
16 - Which of the following is the primary use of an expression vector?
Protein production
17 - Under the influence of which ion does E. coli takes up plasmid from the environment?
Copper
18 - The process by which every type of transformant can be identified is __________
Insertional inactivation
19 - Dysgenesis occurs in every cell of the Drosophila.
FALSE
20 - P-strains of the Drosophila have active P-elements.
FALSE
21 - Hybrid dysgenesis occurs in which of the following cases?
Crossing between M-female and P-male
22 - Retrotransposons transposes through the RNA intermediates.
TRUE
23 - Retrotransposons are of how many types?
2
24 - LTR-retrotransposons are abundantly found in __________
mammals
25 - LINE and SINE are examples of __________
Non-LTR retrotransposon
26 - Which of the following about the L1 LINE family is correct?
Presence of short direct repeats on either end
27 - The consensus sequence of the L1 LINE family has three open reading frames.
FALSE
28 - SINES are transcribed by __________
Polymerase III
29 - The SINE commonly contains the restriction site for the endonuclease __________
Alu I
30 - Splicosome comprises of ______________
RNA and protein
31 - Splicosome is a proteinaceous enzyme.
FALSE
32 - “snurps†are made of ____________
RNA and protein
33 - Which of the following is not a function of snRNPs?
3’ splice site reorganization
34 - 5’ splice site is recognized by which of the following type of RNA present in the splicosome?
U6
35 - Which of the following splicosomal RNAs does not take part in the 5’ site splicing of the intron?
U5
36 - Which of the following component of splicosome recognizes the 3’ splice site?
U2
37 - Which of the following proteins is correctly paired to its function?
RNA annealing factor – loading snRNPs onto mRNA
38 - Which of the following is not involved in creating the early splicosome complex?
U2 binding to branch point site
39 - The subunit association with the mRNA occurs before tRNA recruitment in the case of both eukaryotes and prokaryotes.
FALSE
40 - Eukaryotic mRNA generally codes for a single protein because the eukaryotic translation includes ____________
Monocistronic codons
41 - The same number of auxiliary proteins is used to drive the initiation process of both prokaryotes and eukaryotes.
FALSE
42 - The first amino acid to be incorporated in the eukaryotic polypeptide is ___________
Methionine
43 - Which of the following eukaryotic proteins is an analog of IF2-GTP?
eIF5B-GTP
44 - Recognition of mRNA by 43S pre-initiation complex is mediated by the enzyme ___________
eIF4F
45 - Which of the following protein interacts with the eIF4F for recruiting the pre-initiation complex to the mRNA?
eIF3
46 - mRNA scanning is a cost-effective mechanism.
TRUE
47 - The initiation factors are closely associated with the 3’ end of mRNA through the initiation between the eIF4F and the ___________
Poly A binding proteins
48 - IREs for the process of translation is present in viruses. Their function resembles that of eukaryotic ribosome.
FALSE
49 - How many types of point mutations are able to alter the Genetic code?
3
50 - The alterations that change a codon specific for one amino acid to a codon specific for another amino acid is known as ___________
Missense mutation
51 - Which of the following disease is caused by missense mutation?
Sickle cell anemia
52 - Nonsense mutation is also known as ___________
Stop mutation
53 - Which of the following types of DNA polymerase has 3’→5’ exonuclease activity?
DNA polymerase I
54 - Choose the odd one out with respect to DNA polymerase III.
dna B
55 - Which of the following is used in prokaryotic replication?
DNA polymerase III
56 - DNA polymerase II can polymerase upto ______________ nucleotides per minute at 37ËšC.
50
57 - All mutation in polymerases is lethal except the mutation of polymerase III.
FALSE
58 - Polymerase I has the highest affinity for dNTPs.
FALSE
59 - Polymerase I has two fragments. The residue of larger fragment consists from ____________ residues.
324 – 928
60 - Which of the following is false about klenow fragment?
3’→5’ exonuclease activity
61 - DNA polymerase III has ___________ subunits.
10
62 - Which of the following types of DNA polymerase does not take part in DNA repair?
DNA polymerase III
63 - Topoisomerases I and II differ only on the number of steps required to change the linking number.
FALSE
64 - Which special enzyme introduces negative supercoils in DNA?
Gyrase
65 - Which of the following is not a property of topoisomerase?
Cannot catenate and decatenate
66 - Topoisomerases introduces catenation to promote cell division.
FALSE
67 - Type I topoisomerase can never decatenate catenated circular DNA?
FALSE
68 - The promotion of DNA breaking and rejoining by topoisomerase requires______________
No external enzyme required
69 - Attack of the topoisomerase gives rise to ____________
Phospho – tyrosine linkage
70 - To reseal the DNA backbone where does topoisomerase gets the energy from?
Phosphodiester cleavage
71 - Which of the following does not occur during cell division in prokaryotes?
Multiple decatenations
72 - The active site of the topoisomerase contains a tyrosine residue.
TRUE
73 - mRNA of which of the following organism does not undergo processing?
Bacteria
74 - rRNA and tRNA of prokaryotes does not undergo any post transcriptional processing.
FALSE
75 - Splicing of mRNA occurs after they arrive the cytoplasm.
FALSE
76 - Which of the following is not a type of RNA processing?
Removal of exons
77 - Elongation of transcription and RNA processing are all interconnected.
FALSE
78 - The first RNA processing event is __________
Capping
79 - Capping is done by the addition of __________
Methylated G
80 - Capping occurs after the mRNA synthesis is complete.
FALSE
81 - As the polymerase reaches the end of RNA which of the following event does not occur as a response?
Addition of poly A at the 3’ end
82 - About how many “A†are added to the nascent RNA in the 5’ end during Polyadenylation?
0
83 - The long tail of As is unique to the RNA synthesized by the RNA polymerase __________
II
84 - Plasmid replication is dependent on the host cell.
FALSE
85 - How the plasmid clones can be screened?
By selectable markers
86 - How many restriction sites are contained by a plasmid?
More than 1
87 - Who were the scientists who discovered the plasmid pBR322?
Rodriguez and Bolivar
88 - Under relaxed conditions how many copies of plasmid are present in the cell?
10 – 700 copies
89 - What is the length of the polylinker segment of plasmid?
Less than 100 base pair
90 - The full for of pUC is polylinker university cloning.
FALSE
91 - The host bacterium takes up a plasmid in presence of ______________
Divalent cations
92 - What is the temperature at which bacteria can takes up the plasmid?
-42ËšC
93 - Which gene in the pUC18 vector confers antibiotic resistance to the transformed cells?
AmpR
94 - What is the characteristic of lacZ gene of pUC18 vector among the following?
Encodes for β-galactosidase enzyme
95 - Which one of the following is the first engineered plasmid vector?
pSC101
96 - What is the expanded form of pBR in pBR322?
Plasmid Boliver and Rodriguez
97 - What is incorrect about plasmid?
They are the genetic material of the bacteria
98 - The repressor for the β-galactosidase gene is encoded by ___________
Lac I
99 - Which of the following is a character of ORF?
Intron
100 - With respect to the open reading frame (ORF) which of the following is wrong?
‘AUG’ is the only start codon for both prokaryotes and eukaryotes
101 - With respect to polycistronic mRNAs which of the following is wrong?
Found in eukaryotes
102 - What was the name of the ribosome binding site?
A site
103 - Which part of the ribosome identifies the Shine – Dalgarno sequence?
16S rRNA
104 - Eukaryotic mRNAs recruit ribosomes using the Shine – Dalgarno sequence.
FALSE
105 - Eukaryotic mRNA is read in the 3’ to 5’ direction.
FALSE
106 - Which one of the following is known as the Kozak sequence?
5’…..GNNAUGG…..3’
107 - With respect to the composition of the ribosome which of the following is correct?
60S and 40S makes up the 80S ribosome
108 - Which element of the ribosome plays a key role in mRNA translation?
rRNA of the small subunit
109 - What is the consensus sequence of the Pribnow box?
TATAAT
110 - The Pribnow box is present on the coding strand of the DNA template.
FALSE
111 - The –35 sequence is highly conserved and has a consensus sequence of ___________
TTGACA
112 - The +1 site of conserved promoter sequence is generally a pyrimidine.
FALSE
113 - –10, – 35 and +1 sites are the consensus promoter sites of sigma factor ______________
σ70
114 - The RNA polymerase core enzyme has a high specificity for promoter sites and can perfectly work alone.
FALSE
115 - The complex formed by the polymerase and the promoter DNA is known as the _____________
Closed complex
116 - Negative supercoiling enhances the rate of transcription.
TRUE
117 - The –10 promoter region is rich in ______________ bases.
A, T
118 - Methylation at which of the following bases is possible within the following oligonucleotides?
GCGC
119 - Which is known to be methylated in eukaryotic cells?
Cytosine
120 - Among the following which shows the maximum rate of cytosine methylation?
Plants
121 - Prokaryotic methylation occurs at ____________
CA
122 - How many types of methylation processes are known in eukaryotic cells?
2
123 - De-novo methylation is done in the newly synthesized DNA strand at opposite positions of the methylated sites on the parent strand.
FALSE
124 - Both de-novo methylation and maintenance methylation ensures the methylation pattern is inherited from parent to daughters.
FALSE
125 - Methylation of cytosine increases the transition mutation of cytosine to __________
Thymine
126 - The CpG islands generally consist of how many GC bases?
1000
127 - In humans CpG islands are generally located in the ____________
Promoter region
128 - The Intergenic CpGs are more commonly methylated than in the intragenetic region.
TRUE
129 - Major methylation of CpG islands does not include?
Enhancer
130 - De-novo methylation leads to the phenomenon of genetic imprinting in the offspring.
FALSE
131 - Both the imprinted genes inherited from either parent are expressed in an offspring.
FALSE
132 - The phenomenon of allelic exclusion leads to the inactivation of one allele of a gene. The active allele is known as ____________
Hemizygote
133 - Gene of which of the following protein/enzyme/hormone is an example of paternal Hemizygote?
Igf-2
134 - How many types of specific domains are present in the SR protein?
2
135 - Which of the following components of the splicosome machinery is recruited by the SR protein?
U2AF
136 - SR proteins are not essential for RNA splicing.
FALSE
137 - The presence and activity of SR determines the ___________
Usage of particular splice site
138 - Alternative splicing is regulated by activators and repressors.
TRUE
139 - The Drosophila half-pint protein is _____________
Positive regulator
140 - Most silencer proteins are able to bind to pre-mRNA but cannot recruit the splicing machinery.
TRUE
141 - hrRNPA1 acts as the repressor for the final mRNA form of ____________
HIV
142 - The pre-mRNA binding minor splicosome is also known as ___________
AT – AC splicosome
143 - hnRNPI binds to which segment of the mRNA?
3’ splice site
144 - Alternative splicing of the Troponin T gene produces ____________ alternative forms of mRNA.
2
145 - Which of the following mRNA is an example of having an extended exon?
T-antigen mRNA of monkey virus SV40
146 - Alternative splicing is always used to produce multiple isoforms of proteins.
FALSE
147 - Alternative splicing can be used to switch off a gene’s expression. How many ways are there to achieve it?
2
148 - Alternative splicing was discovered in the year ______________
1977
149 - Which of the following is not a part of the minor splicosome machinery?
U2
150 - Transformation involves the uptake of _____________
Free DNA
151 - What is conjugation?
Transformation of DNA from a donor to the recipient cell
152 - What is transduction?
Bacterial genes are carried from a donor cell to a recipient cell via bacteriophage
153 - In which year Frederic Griffith discovered transformation?
1928
154 - During Frederick Griffith’s experiments what type of colonies were generated by the capsulated pneumococci?
Type S
155 - What is the function of the capsule of the bacterial cells?
Both Virulence and Protection
156 - How many types of bacterial capsule are present for pneumococcus depending on the genotype of the cell?
Infinite
157 - The genetic information is stored in DNA rather than protein.
TRUE
158 - In the following which bacteria only take up their own DNA?
N. gonorrbacae
159 - How many copies of special short nucleotide pair sequences for identification are present in H. influenzae and N. gonorrbacae?
600 copies
160 - What do you mean by competent bacteria?
Able to take up genetic material from surrounding
161 - Competence in a bacteria ___________
Protein
162 - siRNA are produced by __________
Enzymatic action
163 - Which of the following is not the handiwork of siRNA?
Base dimerization
164 - Introduction of ds DNA can repress gene expression.
TRUE
165 - Dicer is __________
RNAse-like enzyme
166 - Which of the following pathways involve the Dicer for gene silencing?
Chromatin modification
167 - The RNAi mediated gene silencing includes the binding of siRNA to form a complex with the target gene called RISC.
FALSE
168 - The RNAi mediated gene silencing is an ATP-dependent procedure.
TRUE
169 - If the siRNA is a complete homolog of the target mRNA sequences what is the net result?
mRNA degradation
170 - Binding of siRNA to the DNA does not lead to __________
Triple helix formation
171 - Which of the following RNAs can induce gene silencing?
miRNA
172 - The miRNAs are transcribed from non-protein encoding genes and are typically __________ nucleotides long.
20 – 25
173 - The first miRNA was identified in C. elegans named __________
Lin-4
174 - Pick the odd one out.
snoRNA
175 - Inactive miRNA undergoes how many cleavages before incorporation into the RISC complex?
2
176 - piRNAs are synthesized in a Dicer dependent mechanism.
FALSE
177 - Stem loop precursors are generally seen in which of the following?
miRNA
178 - How many polypeptides are required for the structural assembly of the ribosome?
More than 50
179 - Which of the following is the slowest process among the following?
Translation
180 - The ribosome is designed in such a way so as to keep up with the speed of the RNA polymerase.
TRUE
181 - Transcription and translation occur in the same compartment in the cases of both prokaryotes and eukaryotes.
FALSE
182 - Transcriptional coupling ensures a fast rate f translation.
TRUE
183 - Ribosome has two subunits with 4 rRNA molecules. Which of the four rRNAs is found in the decoding center of the ribosome?
16S
184 - The large ribosomal subunit in prokaryotes has the sedimentation velocity of ___________
50S
185 - Svedberg unit used to distinguish among the rRNAs and proteins by measuring it’s ___________
sedimentation velocity
186 - Multiple proteins can be synthesized from an mRNA at a time.
TRUE
187 - How many types of protein degradation pathways are seen in a eukaryotic cell?
2
188 - Ubiquitin degradation mechanism recognizes ____________
Both cytosolic and nuclear proteins
189 - Ubiquitin has ___________ of amino acids.
76
190 - Ubiquitin binds to the ___________ amino acid residue for degradation.
Lysine
191 - The Ubiquitin-proteasome degradation pathway is an energy dependent process.
TRUE
192 - Which of the following is a Ubiquitin activating enzyme?
E1
193 - The Ubiquitin-proteasome pathway is an active target for anticancer drugs.
TRUE
194 - Which of the following is the substrate specific enzyme of the following?
E3
195 - The Cdk1 activates which of the following type of Ubiquitin enzymes?
E3
196 - Ubiquitinization always leads to the degradation of the protein.
FALSE
197 - Lysosomes does not have which one of the following properties?
Carrier vesicles
198 - For the process of autophagy the formation of vesicles occurs. The membrane of these vesicles are derived from ___________
Mitochondria
199 - How many kinds of mutation are found in DNA which includes mutation of only one base?
2
200 - What is the overall rate at which new mutations arise spontaneously at any given site on the chromosome per round of replication?
≈ 10-6 – 10-11
201 - The mutation occurs at a random basis within a genome.
FALSE
202 - What is the dinucleotide sequence of microsatellites?
CA
203 - By which process miss-incorporated base can change into a permanent mutation?
Replication
204 - Detection of mismatches and fidelity of replication is maintained by mutation repair system.
TRUE
205 - How many steps are required to attain mismatch repair?
2
206 - In E. coli mismatches are detected by which repair protein?
Mut S
207 - Mut S recruits how many component(s) to the mismatched site?
2
208 - The nicking of DNA is followed by the adherence of a helicase known as __________
Uvr D
209 - Mismatch repair system is ATP dependent.
TRUE
210 - By which enzyme does E. coli tags its parental DNA strand?
Methylase
211 - If the Mut H cuts the DNA at the 5’ side of the mismatch then which nuclease is activated?
Exonuclease VII
212 - What are the eukaryotic components of Mut S and Mut L of E. coli?
MSH, MLH
213 - High level of mutation in the germ cells is acceptable but in somatic cells can be catastrophic.
FALSE
214 - RecA protein of E. coli is involved in the process of ____________
Pairing of homologous DNA
215 - RecBCD and RecFOR in E. coli is involved in the process ____________
Assembly of strand exchange
216 - In bacteria specific proteins are involved in the RecBCD pathway.
FALSE
217 - What is the holiday junction resolving enzyme?
RuvC
218 - RecBCD enzyme has polymerase and transcriptase activity.
FALSE
219 - RecBCD pathway is an ATP dependent process.
TRUE
220 - Chi is the control site of the RecBCD pathway.
TRUE
221 - What are the helicase components of the RecBCD pathway?
RecB, RecD
222 - What is the function of Rec component?
Recognize Chi sites
223 - What are the two components of RecBCD pathway involved as motor parts?
RecB, RecD
224 - What is the speed of driving the RecBCD along the DNA?
More than 1000 bp per second
225 - How many times the frequency is increased by the Chi sites?
≈10 fold
226 - The nuclease activity of the RecBCD is prone to digest the bacterial cell wall from foreign DNA.
FALSE
227 - What is the sequence of the Chi site that is highly found in the E. coli genome?
GCTGGTGGC
228 - If the foreign DNA lacks the Chi site what will happen?
Foreign DNA easily enters the cell
229 - Which of the following is not a target site for repressor molecules?
Promoter sites
230 - Which of the following about the enhancers is false?
They function as promoter sequences
231 - In the case of transcription regulation what is the function of enhancer molecules?
Stimulates the rate of transcription
232 - Gene imprinting involves ___________
DNA methylation
233 - Acetylation of histone increases transcription of gene due to ___________
It loosens the DNA-histone complex thus making it accessible to RNA polymerase
234 - With respect to the methylation of bases which of the following is correct?
It results in localized conversion of A-DNA to Z-DNA
235 - Which of the following about the enhancer sequence is incorrect?
They are not responsible for specificity of tissues
236 - The most commonly observed modification in the histone includes ___________
Acetylation of lysine and phosphorylation of serine
237 - Which of the following about the differences between the prokaryotic and eukaryotic genes are true?
Eukaryotic genes are large, monocistronic and contain introns
238 - With respect to DNA polymerase holoenzyme pick the odd one out.
Presence of DNA
239 - A complete DNA polymerase III holoenzyme contains ____________ subunits.
6
240 - How many polymerases are present in a replication fork?
3
241 - With respect to eukaryotic replication which of the following enzyme is not correctly paired with its function?
RF-C – recruitment, maintenance and coordination of DNA polymerases
242 - The formation of the phosphodiester bond is an example of _________ reaction.
SN2
243 - DNA synthesis is known as a coupled process.
TRUE
244 - DNA helicase travels along _________
Lagging strand template in 5’→3’ direction
245 - DNA polymerase III holoenzyme does not need to interact with the helicase during replication.
FALSE
246 - Binding of polymerase III and helicase ensures helicase efficiency.
TRUE
247 - Association of primase with DNA template is brought about by the interaction of primase with _________________
Helicase and SSB protein
248 - How is the strength of the interaction between primase and helicase which regulates the length of Okazaki fragments?
Strong association short fragment
249 - Which of the following enzyme is not required for the synthesis of lagging strand?
Gyrase
250 - Length of Okazaki fragments in eukaryotes ranges between ____________ nucleotides.
100 – 400
251 - Polymerization of dNTP by DNA polymerase is in 3’ → 5’ direction.
FALSE
252 - Which of the following is the most energetically costly process among the following?
Translation
253 - The accurate ordering of amino acids in a polypeptide is determined by the direct interactions between the mRNA template and the amino acid.
FALSE
254 - Who was the first to propose indirect interaction between mRNA template and amino acids to produce accurate ordering of amino acid in a polypeptide chain?
Francis H. Crick
255 - How many major components are used for the process of translation?
4
256 - Which of the following is not a property of open reading frame?
Starts and ends at either end of the mRNA.
257 - Both Prokaryote and Eukaryote has one start codon 5’-AUG-3’.
FALSE
258 - The start codon has a vital role to play in incorporating the specific amino acids in the peptide chains.
TRUE
259 - How many reading frames are applicable in case of translation?
3
260 - Both prokaryotes and Eukaryotes have one ORF.
FALSE
261 - Shine – Dalgarno sequence is also known as the __________
RBS
262 - Which component of the rRNA binds to the mRNA?
16S
263 - The phenomenon of translating two a protein by two ribosomes is known as translational coupling.
FALSE
264 - Replication of chromosome occurs during the ____________ phase.
S
265 - It is important to replicate the DNA correctly and only once.
TRUE
266 - Selection of replicator occurs in ___________ phase.
G1
267 - Activation of the origin of replication occurs in ____________ phase.
S
268 - The replicator selection is mediated by the formation of pre-replicative complex. It comprises of _________________
An ORC, two helicase loaders and a helicase
269 - The pre – RCs are auto-activated as soon as the cell enters the S – phase.
FALSE
270 - Which of the following is wrong about the cyclin dependent kinases?
Promotes formation of new pre – RCs
271 - Active cyclin dependent kinase is absent in ____________ phase.
G1
272 - How many types of vector systems are used in eukaryotic plants?
3
273 - Ti plasmid is the only known plasmid of plant.
FALSE
274 - The Ti is referred to as _____________
Tumor inducing
275 - In which of the plant is the crown gall disease caused?
Stem
276 - The size of the Ti plasmid is around ___________
More than 200 kb
277 - The part of the bacterial plasmid incorporated in the plant genome includes ___________
Only T-DNA
278 - The size of the T-DNA is around ____________
15 – 30 kb
279 - The T-DNA contains how many genes for cancer in the plant?
8
280 - The sole purpose of the infection of plants by the Ti plasmid is the formation of cancer.
FALSE
281 - How many process are used to form the chimera Ti plasmid?
2
282 - The transposable elements of bacteria are generally retrotransposons.
FALSE
283 - The IS elements can be identified by the presence of __________
50 bp inverted repeat
284 - Direct repeats in the IS element are present __________
Within the inverted repeat
285 - The direct repeat within the IS element has a length of __________
5-11 bp
286 - The enzyme that catalyzes the transposition of an IS element is called __________
Transposase
287 - Transposase restriction mechanism of the IS element restricts the transposon and the target DNA in a combination of which of the following?
Blunt end cut for transposon and sticky end cut for target DNA
288 - Which of the following functions is not performed by transposase?
Formation of the RNA intermediate
289 - The central block of the composite transposable element consists a gene for __________
Antibiotic resistance
290 - Which of the following is a non-composite transposon?
Tn3
291 - Which of the following about the P-element is false?
25 bp inverted repeats
292 - Hybrid dysgenesis is caused by which of the following transposable element?
P-element
293 - How many nucleotides of the growing RNA chain remain base paired with the template DNA?
10
294 - The transcription bubble formed for facilitating RNA synthesis is about _____________ nucleotides long.
17
295 - The nascent RNA forms a double helix with the non – coding strand.
TRUE
296 - How many proof-reading activities does RNA polymerase have?
2
297 - The RNA polymerase can remove only the incorrect bases from the nascent RNA.
FALSE
298 - The Gre factor enhances the hydrolytic editing function of the polymerase.
TRUE
299 - E. coli polymerase adds upto _____________ nucleotides per second.
40
300 - The Gre factor is homologous to the eukaryotic factor _____________
TFIIS
301 - In the beads on a string model, the bead is made up of __________
8 histone proteins
302 - The unpacked stretches of DNA are the extra chromosomal load found in the eukaryotic genome.
FALSE
303 - How many types of histone molecules are found in nature?
5
304 - Nucleosome is made up of __________
DNA, histone core protein, linker H1
305 - Histones have a high content of negatively charged amino acids.
FALSE
306 - With respect to assembly of every core histone which of the following is wrong?
2 α helices and an unstructured loop
307 - Which of the following histone pairs forms tetramers in solution?
H3, H4
308 - With respect to the “tails†of the histone molecules which of the following is not true?
Required for the association of nucleosome
309 - How many contacts are observed between the DNA and the histone core protein?
14
310 - Association of DNA and histone is mediated by _________
Hydrogen bonding
311 - For the correct addition of amino acid to the growing polypeptide chain which of the following does not play any role?
Loading of initiator tRNA to the P site
312 - The events controlling the correct addition of amino acid is controlled by ____________ proteins.
2
313 - The auxillary protein required for the elongation of polypeptide is energy independent.
FALSE
314 - Aminoacyl tRNA needs an escort to carry them to the ribosome bound mRNA.
TRUE
315 - Once the tRNA is aminoacylated, EF-Tu binds to the tRNA at the ____________
3’ end of the tRNA
316 - The activation of GTPase activity of the enzyme EF-Tu occurs after its binding to the aminoacylated tRNA.
FALSE
317 - The only fidelity testing of the translation is by observing the energy difference involved in the correct and incorrect base pairing.
FALSE
318 - How many mechanisms are involved in the maintenance of the fidelity of translation?
4
319 - Which part of the large subunit helps in the formation of the peptide bond?
23S rRNA
320 - Which of the following steps is not required for the process of translocation?
Frame shift in hybrid states
321 - The completion of translocation requires the action of the factor _________________
EF-G
322 - PCR is a DNA amplifying in vivo method.
FALSE
323 - Which of the following is a mismatch?
Template – double stranded DNA
324 - Annealing of primer is facilitated by complementary region.
TRUE
325 - Primer used for the process of polymerase chain reaction are ______________
Single stranded DNA oligonucleotide
326 - Polymerase used for PCR is extracted from _____________
Thermus aquaticus
327 - How many DNA duplex is obtained from one DNA duplex after 4 cycles of PCR?
16
328 - At what temperature do denaturation of DNA double helix takes place?
94Ëš
329 - At what temperature do annealing of DNA and primer takes place?
54Ëš
330 - The temperature at which DNA synthesis takes place is 74ËšC.
TRUE
331 - How many charged tRNA substrate is used for the polypeptide formation at a time?
2
332 - The peptidyl transferase reaction is a result of ____________ consecutive steps.
2
333 - The polypeptide bond formation is an ATP dependent process.
FALSE
334 - During the addition of amino acid, the codon on the mRNA is identified by the direct interaction of the anticodon loop of the tRNA.
FALSE
335 - The peptidyl transferase reaction center of the ribosome contains ___________ sites.
3
336 - How many channels are observed in a ribosome molecule?
3
337 - The channel for the entry of the mRNA into the decoding center is a crucial feature for the proper decoding of them RNA.
TRUE
338 - The polypeptide elongation channel allows the formation of which of the following structures?
α – helix
339 - X-chromosome inactivation is known as ______________
Dosage compensation
340 - The proposal for the concept of X-chromosome inactivation in female XX-chromosomes was experimentally shown in ___________
Mice
341 - The maternal X-chromosome is inactivated during Dosage compensation.
FALSE
342 - Female mammals are called genetic mosaics.
TRUE
343 - The best genetic mosaicism is observed in which of the following?
Cat
344 - Barr body is the ___________
Inactive X chromosome
345 - What changes occur in the chromosome to make it inactive?
Methylation
346 - The X-chromosome once inactivated remains inactive throughout the life in all the cells of the body.
FALSE
347 - All genes on the inactivated X chromosome are transcriptionally silent.
FALSE
348 - The functional product of the Xist gene is ___________
RNA devoid of ORF
349 - The one which is able to repress the production of the Xist transcript is the active X chromosome.
TRUE
350 - In which stage of the cell cycle the Barr body can be identified?
Interphase
351 - The β subunit of polymerase has a function of ____________
Catalytic center
352 - Presence of the heparin promotes transcription.
FALSE
353 - The β’ subunit of polymerase has a function of ________________
Cation binding
354 - The RNA polymerase core enzyme converts into a holoenzyme on the addition of the _________ subunit.
σ
355 - Four types of σ factors are known of them which one is heat stable?
σ70
356 - What is the function of the ω subunit of RNA polymerase?
Subunit association
357 - Which of the following is not part of the RNA polymerase core enzyme?
σ
358 - The bacterial system has _____________ RNA polymerases.
3
359 - Reverse transcriptase produces DNA from RNA.
FALSE
360 - Which of the following serves as the first primer in RT – PCR for eukaryotic RNA?
Oligo T
361 - In RT – PCR the enzyme deoxynucleotydil transferase adds poly – G residues in the __________
3’ end of cDNA
362 - The digestion of mRNA during RT – PCR is carried out by the enzyme ____________
RNase H
363 - How many primers are used in the process of reverse transcriptase amplification?
2
364 - From which organism is the enzyme reverse transcriptase isolated?
Virus
365 - The cDNA library provides several advantages over RT – PCR.
FALSE
366 - ________________ is a modification of RT – PCR.
RACE
367 - The main problem in the formation of the chimera Ti plasmid is _____________
No unique restriction site
368 - The binary vector strategy uses two different vectors for the production of the single chimera molecule by recombination.
FALSE
369 - Which of the following does not play any role in the infection of plant cell by the Ti plasmid of A. tumefaciens?
T-DNA
370 - Disarming of Ti plasmid is ____________
Removal of the T-DNA
371 - Insertion of the T-DNA into the host genome depends on the T-DNA itself.
FALSE
372 - The Ti cloning vector pBIN19 contains which of the following genes?
Kanamycin resistant gene
373 - Transformants of pBIN19 are selected by growing them in solid agar media with ampicillin.
FALSE
374 - Introduction of new gene through Ti plasmid should be done in ____________
Callus
375 - How the host specificity is achieved by the specificity gene of the Ti plasmid?
Acetosringone released by a wounded part of the plant
376 - The origin of replication is rich in __________
A, T
377 - How many origin of replication are present in the E. coli genome ___________
1
378 - There are two repeated motifs critical for ori C function. They are ___________
9 mer and 13 mer
379 - With respect to the ori C motif choose the correctly paired option.
13 mer = 3 times
380 - Which of the following is not paired with its correct function?
13 mer = binding site for replication initiator protein
381 - Which of the following is not a function of Dna A?
Initiates DNA melting
382 - The replication terminus is a segment of a number of ____________ bp.
350000
383 - The replication terminus involves ____________ identical non palindromic termination site.
6
384 - The termination sites are one way valves known as non-polar valves.
FALSE
385 - The arrest of replication fork motion at Ter sites require the action of ____________ protein.
Tus
386 - The topological unlinking of DNA in prokaryotes is promoted by ______________
Topoisomerase
387 - Helicase attaches to the leading strand during replication.
FALSE
388 - The primer used for lagging strand synthesis in prokaryotes is an RNA primer.
FALSE
389 - Which enzyme is used to remove the primer from the Okazaki fragment?
Polymerase
390 - The functional unit in which genes are arranged consecutively is known as ___________
Operon
391 - The investigation of the lac operon for the metabolism of lactose was done by __________
Francois Jacob and Jacques Monod
392 - Presence of lactose itself induces the production of β-galactoside transferase.
TRUE
393 - How many enzymes are produced in the lac operon under the same promoter?
3
394 - Defects in which regions can affect the activity of the lac operon?
i and o
395 - If the lac operon of the genome of bacteria is always active it has a defect in which region of the operon?
i
396 - Lac operon follows a trans-acting control mechanism.
TRUE
397 - According to the repressor of lac operon which of the following are false?
It binds to the promoter region
398 - If there is an insertion mutation in the operator of the lac operon, the expression of the lac structural gene will be __________
Constitutively expressed
399 - The complete expression of the lac operon requires __________
Allolactose and cAMP
400 - What effect would a loss-of-function mutation have on the expression of the gene encoding the catabolite activator protein of the lac operon?
Low expression in the presence of lactose and off in its absence, regardless of the presence or absence of glucose
401 - Mutation in the regulatory gene of a positively controlled operon can be identified by __________
Operon repression
402 - In the case of lac operon, the gene expression is inhibited by __________
Interaction of repressor with operator
403 - Which of the following is false about bacterial tryptophan operon?
The co-repressor is the catabolite activator protein
404 - Attenuator in the tryptophan operon is the __________
Leader sequence in the tryptophan mRNA coding for many tryptophan residues
405 - The 3’ end of tRNA is __________
3’ ACC 5’
406 - Thymine is present in tRNA.
TRUE
407 - With respect to tRNA which of the following is not its characteristic?
Double helix molecule
408 - How many loops are present in the clover leaf model of tRNA?
4
409 - Why the variable loop is named so?
Variable number of bases
410 - The distance between the amino acid binding site and the anticodon site is ______
70 Ã…
411 - What is the angle between the D loop and the anticodon loop?
90Ëš
412 - Which of the following does not contribute to the stability of tRNA?
Hydrophobic interactions
413 - For the charging of tRNA molecules, the acyl linkage occurs between the carboxyl group of the amino acid to the ____________
2’ hydroxyl group of A
414 - The formation of the acyl linkage is significant for protein synthesis even though it is a high energy bond.
TRUE
415 - The joining of the amino acid to the tRNA requires ___________ steps.
2
416 - The principle driving force for adenylation reaction during the formation of the aminoacyl tRNA is carried out by ___________
Pyrophosphatase
417 - How many types of tRNA synthetases are found?
2
418 - How many tRNA synthetases are found in a cell?
20
419 - The quaternary structure of which of the aminoacyl tRNA synthetase is the odd one among the following?
Glycine
420 - Which of the following pair is an example for using only one type of tRNA synthetase in bacteria?
Glutamine and glutamic acid
421 - Which of the following parts of the mRNA determines the specificity of the amino acid attached?
Acceptor stem
422 - Any mutation in the sequence of the acceptor stem does not pose a threat to the amino acid incorporation.
FALSE
423 - For the addition of amino acids to the tRNA molecules the tRNA synthetases rely on the guidance provided by the anticodon sequence.
FALSE
424 - The set of tRNA determinants that enable synthetases to discriminate among tRNAs are called ___________
Second genetic code
425 - The most common signal for termination of transcription is self complementation.
TRUE
426 - The stem of the hairpin loop of RNA consists mostly of _____________
G, C
427 - The hairpin structure generated in the RNA is followed by a stretch of oligonucleotide complementary to the base ____________
A
428 - A stretch of which nucleotide in the DNA acts as the termination signal?
Poly A
429 - The rho protein has ____________ subunit.
6
430 - The rho proteins are ATP independent proteins.
FALSE
431 - The rho protein binds to the RNA recognizes a special structure. It consists of ____________ nucleotides.
40
432 - The rut sites are rich in ____________ residues.
C
433 - The rho protein can even bind within operons to terminate transcription.
FALSE
434 - Which of the following statement is false about DNA?
Abundantly found in cytoplasm
435 - Which of the following function of DNA is necessary for the purpose of evolution?
Mutation
436 - Which of the following combination is a correct observation for the transformation experiment performed by Griffith?
Type IIIS (living) + mouse = dead
437 - Fredrick Griffith’s experiment involving Streptococcus pneumonia lead to the discovery of____________
Transforming principle
438 - Definite results proving DNA to be genetic material was given by __________
Avery, Macleod and MacCarty
439 - Which of the following statements regarding the mechanism of transformation in Bacillus subtilis is false?
While translocation of exogenous DNA, both strands gets passage into the cell
440 - What were the main criteria taken under consideration for the experiment by Hershey and Chase?
DNA contains phosphorus, protein contains sulfur
441 - What combination of radiolabelling is correct in case of Hershey and Chase’s demonstration of DNA as genetic material in T2 bacteriophage?
31P, 35S
442 - Recently, scientists have developed a procedure in which protoplasts of E. coli could be directly infected with the phage DNA. This process is termed as_________
Transfection
443 - According to Mendel’s experiments gene carry genetic information from parents to offspring’s. On which plant did he perform his experiments?
Pisum sativam
444 - Plasmids are ____________
Circular double stranded DNA
445 - What stores the genetic information in DNA?
Nitrogenous base
446 - DNA always carries the genetic information for all organisms.
FALSE
447 - What is the major type of RNA produced in the cell required for translation?
rRNA
448 - Which of the following does not affect the formation of hybrid DNA?
Pressure
449 - Which of the following is not termed as hybridization?
DNA from male and female of same species
450 - What is a probe?
Either purified or synthesized single stranded DNA
451 - Why is a probe labeled?
Improve location identification
452 - In how many ways a DNA can be labeled?
2
453 - What is the function of polynucleotide kinase?
Addition of γ – phosphate at 5’ – OH
454 - Fluorescent labeling is an important phenomenon in case of hybridization and manipulations in molecular biology.
FALSE
455 - Radiolabelling is generally brought about by addition of radioactive phosphorus.
TRUE
456 - During electrophoresis denaturation of the double stranded DNA is brought about by __________
Treatment with alkali
457 - In case of northern blotting the hybridization occurs between two RNA molecules.
FALSE
458 - Northern blotting is performed for ____________
Quantification of RNA
459 - The process by which a probe is used to screen a library is known as ___________
Colony hybridization
460 - Which of the following is not a part of a gene?
Ori
461 - What is the correct order for increasing gene density?
Human, Fruit fly, Bacteria, Virus
462 - Which of these factors contribute to a decrease in gene density?
Intergenic sequence
463 - What do you think is the requirement of Intergenic DNA in higher organisms?
To avoid viable mutations
464 - Which of the following is not a character of unique Intergenic DNA?
Palindromes
465 - Which of the following is responsible for the formation of Pseudogenes?
Reverse transcriptase
466 - With respect to microsatellite DNA which of the following is correct?
100 bp units
467 - Genome – wide repeat unit are generally transposable elements.
TRUE
468 - Repeated DNA can be referred to as junk DNA.
FALSE
469 - The simpler the organism the more likely they are to have transposable elements.
FALSE
470 - In which phase bacteria develop competence?
Late phase
471 - In which bacteria competence pheromones was first identified?
B. subtilis
472 - What is the percentage of DNA molecules taken up by competent cells during the transformation?
0.2-0.5
473 - Transformation of E. coli does not occur.
FALSE
474 - During conjugation the Donor cell have cell surface appendages known as ____________
F pili
475 - What is the size of the F factor that is involved in conjugation?
105 base pairs
476 - In how many states the F plasmid can occur within bacteria?
2
477 - By which of the following methods does the F plasmid integrates into the bacterial genome?
Recombination
478 - High frequency recombination cell contains an integrated F factor. What is the name of such a cell?
Hfr cell
479 - What is the strain of the Hfr+ cell where the F factor is integrated near the tbr and leu loci?
Hfr H
480 - Transformation, transduction and conjugation occur in every bacterial cell.
FALSE
481 - What is the central protein of homologous recombination?
RecA
482 - What is the joint molecule?
Rec A bound three stranded structure
483 - The RuvAB complex specifically recognizes the Holliday junction in an ATP dependent manner.
TRUE
484 - Which component cleaves the specific DNA strands at the Holliday junction?
RuvC
485 - After cleaved by RuvC the resulting ligated recombination products will only be the splice product.
FALSE
486 - What is the cleavage site of RuvC?
5’….A/TTTG/C….3’
487 - What is the source of energy during the action of SPO11?
Cleavage of phosphodiester bond
488 - What are the components of the MRX protein?
MreII, Rad50, Xrs2
489 - Processing of the DNA at the break site occurs at the 3’ end.
FALSE
490 - How many cycles are required for the configuration of chromosomes?
2
491 - What is non-disjunction?
Failed alignment
492 - For which biological phenomenon homologous recombination is critical?
Meiosis
493 - What are homologs?
Pair of chromosomes
494 - What is the function of the Spo11 in meiotic recombination?
Introduction of DSB
495 - How many subunits of Spo11 are involved in the process of cleavage of DNA?
2
496 - How is the extent of supercoiling measured?
Lk – Lk0
497 - If Lk < Lk0 then DNA is ____________
Negatively coiled
498 - What is ΔLk and Lk0 dependent upon?
Length of DNA
499 - Strand separation is easily accomplished in positively supercoiled DNA.
FALSE
500 - Which of the following organism has been found to have a positively supercoiled DNA?
Thermus aquaticus
501 - Which of the following is not true about positive supercoils?
Strand separations require low energy
502 - Packaging of DNA around nucleosome is known as ____________
Toroid writhes
503 - The nucleosome is seen to have negative supercoils.
TRUE
504 - Which of the following is known to relax supercoiled DNA?
Topoisomerase
505 - With respect to topoisomerases which of the following is true?
Requires ATP
506 - Nucleosome was first described in 1974 by ___________
Roger Kornberg
507 - The extent of chromosome coiling in non – dividing cells is _________
Euchromatin
508 - The whole length of DNA is transcriptionally active.
FALSE
509 - Why are chromosomes condensed?
To facilitate distribution in daughter cells
510 - At which phase do transcription ceases?
Prophase
511 - The part that plays a critical role in even distribution of parental DNA during division is ___________
Centromere
512 - With respect to centromere which of the following is wrong?
Facilitates even distribution
513 - The protein that binds to the spindle fibres are known as centromeric proteins.
FALSE
514 - Centromeric DNA was initially defined in ___________
Yeast
515 - How many satellite sequence elements are present in yeast centromere?
3
516 - The centromere is A/T rich region.
TRUE
517 - Which alternate form of histone is seen in centromeric histones of humans?
CENP-A
518 - Telomere is not related to __________
Division
519 - Which of the following nucleotides is rich I telomere of an organism?
G, C
520 - How does telomerase activity depend on age?
Does not occur
521 - In cancer telomerase activity __________
Increases
522 - How many types of DNA libraries are possible?
2
523 - In the following type of libraries pick the odd one out.
cDNA library
524 - Which enzyme is involved in the synthesis of the DNA over an RNA template?
Reverse transcriptase
525 - For the construction of DNA library what is the range of genomic DNA that has to be cloned into the vector?
Less than 100 to mega bases
526 - Which of the following enzymes is responsible for the digestion of the RNA strand in the RNA-DNA hybrid?
RNase H
527 - cDNA is synthesized from __________
mRNA
528 - During storage of DNA fragments for making library, larger fragments are having more chances of getting lost.
TRUE
529 - What is the characteristic of the DNA that is used for the construction of library?
Plasmid and naked DNA
530 - What is the state of phage cloning vector that is used for the construction of library?
Unpackaged phage
531 - Which enzyme is used to avoid ligation of separate DNA?
Phosphatase
532 - Partial digestion is preferred for the fragmentation of DNA.
TRUE
533 - What is the significance of “c†in cDNA library?
Copy DNA
534 - mRNA can be readily separated from lysed eukaryotic cells adding magnetic beads. What is the sequence of this magnetic bead?
Oligo T
535 - What is the significance of SI nuclease?
Cleavage of hooks
536 - How is the genetic material expressed?
By transcription and translation
537 - RNA polymerase requires a DNA primer for RNA synthesis.
FALSE
538 - The transcription process carried out by the RNA polymerase is very accurate but less accurate than replication.
TRUE
539 - Which of the following RNA polymerases are responsible for the production of 5S rRNA?
RNA polymerase III
540 - Which RNA polymerase deals with the production of mRNA?
RNA polymerase I
541 - The eukaryotic subunit of RNA polymerase homologous to the ω subunit of bacterial RNA polymerase is ___________
RPB6
542 - The E. coli RNA polymerase adds __________ nucleotides per second.
40
543 - The RNA polymerase holoenzyme has the structural formula of ___________
α2ββ’ωσ
544 - The α subunits of polymerase has a function of ____________
Promoter binding
545 - With respect to polymerization of amino acids which of the following statements is wrong?
The polymerization machinery consists of fifty proteins and two RNA molecules
546 - Ribosome begins its translation at the 3’ end of the mRNA in prokaryotes.
FALSE
547 - Check which one of the following mechanisms is wrongly paired with its location of occurrence?
Post transcriptional mechanism – ER
548 - With respect to the subunits of ribosome which of the following is wrongly paired?
Large subunit = decoding center
549 - An mRNA bearing multiple ribosomes is known as______________
Polysome
550 - What is the actual substrate for each round of amino acid addition?
tRNA
551 - The reaction to form a new peptide bond is known as the peptidyl transferase reaction.
TRUE
552 - Where does ribosome gets the energy for the formation of peptide bond?
Breaking of acyl bond
553 - With respect to the mRNA – ribosome complex for translation mechanism which of the following pair is wrong?
E site – polypeptide exit site
554 - Only a single stranded RNA can pass through the ribosome for decoding.
TRUE
555 - How many channels are present in the ribosome?
3
556 - Which base undergoes spontaneous damage under physiological conditions?
Cytosine
557 - With which base uracil pairs in the opposite strand upon replication?
Adenine
558 - Which base is generated due to the deamination of adenine?
Hypoxanthine
559 - Which base is generated by the deamination of guanine?
Xanthine
560 - Bases in the mRNA undergo depurination.
FALSE
561 - In vertebrate DNA, which base is frequently present in place of cytosine on which methyl transferase acts?
5-methylcytosine
562 - Which base is generated by the deamination of 5-methylcytosine?
Thymine
563 - Which laboratory mutagen is prone to mutation of DNA?
N-methyl, N1-nitro, N-nitrosoguanidine
564 - Which site of guanine is the site for mutation?
C-6
565 - What is the product by mutation by oxidation of DNA?
7,8-dihydro-8-oxoguanine
566 - To which base OXOG base pairs?
A, C
567 - In the case of thymine dimer which type of ring compound is formed?
Cyclobutane
568 - 5-bromouracil is the analog of which base?
Thymine
569 - Bleomycin is the anticancer agent.
TRUE
570 - In the following compound which is one of the intercalating agents?
Ethidium
571 - Where do the chimera molecules propagate?
Host
572 - Mutation sometimes assists the uptake of DNA material. It is a transformational regulator.
TRUE
573 - What is the DNA sequence for cleavage by the endonuclease that is coded by hsdR?
AACGCNNTGC
574 - In which of the following methylation dependent restriction system is necessary?
mcrA
575 - The DAM protein methylates which residue in the sequence GATC?
G
576 - The quality and yield of plasmid DNA preparation both are enhanced by end A mutation.
TRUE
577 - What is the main characteristic that is present in a useful transformation method?
Efficiency of transformation
578 - Plasmids contribute to the survivality of its host cells.
TRUE
579 - Which of the following types of resistance is not provided by the plasmid for its host?
Phage infection
580 - The drug, quinolone, resistance is observed in which of the following?
Klebsiella pneumoniae
581 - Certain products produced by the plasmid genes can kill other microbes in its vicinity.
TRUE
582 - The binding of U2 snRNP is aided by BBP and thus promotes 5’ site splicing.
FALSE
583 - Which three snRNPs together make the tri-snRNP particle?
U4, U5, U6
584 - Which of the following pairs is held together by the complementary base pairing in the B complex of splicosome?
U4, U6
585 - Which of the following complexes produces the active site of the splicosome?
C complex
586 - Formation of the active site only in the C complex is a necessity for avoiding wrong splicing.
TRUE
587 - Group II introns are spliced by the splicosome complex.
FALSE
588 - The branch point site conserved sequence for group II intron is ___________
G
589 - Which of the following groups can perform self splicing?
rRNA, mtRNA
590 - Self-splicing is achieved by the formation of specific structures within the introns.
None of the mentioned
591 - What is the correct definition of excision repair?
Removal of a single damaged nucleotide
592 - How many types of excision repair systems are known?
2
593 - Why recombinational repair system is called double strand break repair?
Both strands are broken
594 - Which enzyme is activated during double stranded break?
Translesional polymerase
595 - What is the main enzyme that plays a major role in formation of thymine dimer?
DNA photolyase
596 - Which two Uvr component molecules scan the DNA during nucleotide excision repair?
UvrA, UvrB
597 - After creation of the bubble which Uvr component are recruited?
Uvr C
598 - Which complex in E. coli performs in translesion synthesis?
DNA polymerase IV, DNA polymerase V
599 - In humans which DNA polymerase is involved?
DNA polymerase Æž
600 - The genes encoding the translesional polymerases are expressed as part of a pathway known as the SOS response.
TRUE
601 - In eukaryotes the other name of PCNA is __________
Sliding clamp
602 - In SOS repair system cleavage of LexA and UmuD is mediated by ___________
RecA
603 - What are the two fundamental components of NHEJ?
KU70, KU80
604 - NHEJ is ubiquitin independent in eukaryotic organisms.
FALSE
605 - In the following compounds which are involved in nucleotide excision repair?
XPA, XPC, XPD, XPG
606 - Without using primers for RNA synthesis the polymerase produces small stretches of RNA of _____________ nucleotides.
10
607 - To facilitate binding of σ70 the melting of the template and non – template strands occurs between the positions ____________
-11 to +3
608 - The isomerisation of σ70 of bacterial polymerase is an energy dependent process.
FALSE
609 - With respect to the formation of a complex between polymerase and DNA template which of the following is correct?
Open: irreversible; Closed: reversible
610 - How many channels are found in the RNA polymerase clamp?
5
611 - The channel that allows the exit of the coding strand is known as ____________
NT channel
612 - Region 1.1 of the σ factor mimics the DNA and is negatively charged.
TRUE
613 - RNA polymerase adds the nucleotides de novo. The first nucleotide added by the polymerase is ____________
ATP
614 - The ternary complex is formed by the polymerase, DNA duplex and the nascent RNA.
FALSE
615 - After the binding of polymerase to the DNA template the σ factor is ejected.
FALSE
616 - Which of the following facilitates nucleosome positioning?
DNA – binding protein
617 - Which of the following regions promote histone – DNA association?
A, T
618 - With respect to end terminal modification of the histone tail which of the following options is true?
Modifications – involvement in gene expression
619 - Which of the following is a function of a modified histone tail?
Interaction with chromodomains
620 - Bromodomains of proteins are associated with phosphorylated histone tails.
FALSE
621 - Which of the following enzymes of transcription commonly contains a bromodomain?
TFIID
622 - Which of the following enzymes is not correctly paired with its function?
Methyl transferase – adds methyl group to serine
623 - Which of the following is not promoted by histone tail modification?
Nucleosome sliding
624 - Which of the following is not required for DNA sequencing?
Cloning
625 - End labeled DNA sequencing is known as dideoxy method of sequencing.
FALSE
626 - The 32P is added at the 3’ end by polynucleotidyl kinase.
FALSE
627 - The end labeled fragment is cleaved in how many pieces?
2
628 - Restriction digestion is the only process to achieve sequencing by the Maxem and Gilbert method.
FALSE
629 - The denatured strands cannot be separated.
FALSE
630 - What are the basic base-specific cleavage sites used in Maxem and Gilbert method?
G, C, A+G, C+T
631 - Which step is not involved in base-specific cleavage of DNA fragment?
Induction of random strand break
632 - The process of electrophoresis is the key to sequencing.
TRUE
633 - The dideoxy method is also known as _____________
Sanger’s enzymatic sequencing
634 - Which enzyme is used for the replication in case of Sanger’s method of sequencing?
Larger subunit polymerase I
635 - With respect to Sanger’s enzymatic method of sequencing pick the odd one out.
Restriction digestion
636 - The four reaction mixtures that were prepared, contained ____________
dCTP, ddTTP, dGTP, dATP
637 - ddNTP acts as the chain radioactive markers.
FALSE
638 - Strand separation for DNA sequencing is done to ____________
obtain consecutive sequence as per termination
639 - The position of band during electrophoresis indicates the dNTP used as a chain terminator in that mixture.
FALSE
640 - The transcription starts with a purine that ends with a __________
Triphosphate
641 - The enzyme used for capping mRNA is a __________
Transferase
642 - The guanyl residue added during capping is added in the same direction as the other nucleotides.
FALSE
643 - How many methylated nucleotides are observed during capping?
2
644 - During capping the methylated penultimate base is known as the __________
Cap 1
645 - The specific sequence present in the DNA for the triggering of polyadenylation is __________
3’….TTATTT….5’
646 - The poly A adding site is 5’….GA….3’.
FALSE
647 - The requirements of polyadenylation site does not include __________
Polyadenylation after GU rich region at cleavage site
648 - Regulation of enzyme activity is accomplished in ___________ steps.
2
649 - Binding of small molecules to enzymes leads to feedback inhibition.
TRUE
650 - The regulatory molecules bind to the catalytic site of an enzyme to regulate its activity.
FALSE
651 - Which of the following is incorrect about the inactive state of the Ras protein?
Cell proliferation activation
652 - The regulatory proteins bind to the enzymes with covalent linkages.
FALSE
653 - The activity of which of the following proteins is not regulated by covalent modifications?
Cell signaling
654 - Protein kinases transfer phosphate groups to the side chains of which of the following?
Serine
655 - Like kinases all phosphatases are also species specific in nature.
FALSE
656 - Which of the following is false about amino acid modification and activity?
Nitrosylation of arginine residue
657 - The cAMP-dependent protein kinase has how many subunits?
4
658 - The two strands of cccDNA can be easily separated without any breakage of bonds.
FALSE
659 - Passing of one strand through the other in order to get separated is known as _______
Linking number
660 - Linking number is always a ___________
Integer
661 - Linking number is the sum of which geometric components?
Twist and writhe
662 - 3 – dimension structure of cccDNA is ___________
Torsionally stressed
663 - Plectonomic writhe is __________
Long axis twisted around itself
664 - Interwound writhe and spiral writhe are topologically different.
FALSE
665 - Twist and writhe are interconvertible.
TRUE
666 - What is the relation between linking number (Lk), writing number (Wr) and twist number (Tw)?
Tw = Lk – Wr
667 - How can we remove supercoils from cccDNA?
Treat with DNase
668 - How many classes of sequences are carried by the recombination site?
2
669 - CSSSR can generate ____________ Different types of DNA rearrangement.
3
670 - In recombinase recognition sequences what is the short sequence?
Crossover region
671 - What are the two families of conservative site specific recombinases?
Serine and tyrosine
672 - Site specific recombination is ATP dependent process.
TRUE
673 - What are the two proteins which create site specific recombination?
DNA topoisomerases and Spo11
674 - How many single strands are generated during recombination?
4
675 - Which recombinases cleaves the four strands before strand exchange occurs?
Serine
676 - What is the correct pair of the four segments (R1, R2, R3, and R4)?
R2 and R3, R1 and R4
677 - What is the nature of the DNA complex formed by the recombination process?
Hydrophobic
678 - How many mechanisms are involved in the recombination process?
3
679 - How does tyrosine recombinase acts?
Cleaves and rejoin two DNA pairs one after another
680 - What is the enzyme involved in the tyrosine recombination process?
Cre recombinase
681 - What is the name of the site where Cre enzyme acts?
LOX
682 - What is the function of Salmonella Hix invertase?
Inversion of chromosomal region
683 - Which of the following is not a feature of the genetic code?
Ambiguous
684 - The codon is a ____________
Triplet
685 - There is one amino acid for one genetic code.
FALSE
686 - One base in an mRNA can be used for more than one codon.
FALSE
687 - Which of the following is not a termination codon?
UAC
688 - In case of mitochondrial genetic code UGA is a ____________ codon.
Tryptophan
689 - The wobble hypothesis was devised by ____________
Francis Crick
690 - The distribution of codon is made in such a way to minimize mutation effect.
TRUE
691 - Point mutation of the second place mutating “A†with “T†will result in a similar if not the same amino acid.
FALSE
692 - Which of the following genetic code shows ambiguity?
UGA
693 - The type of DNA amplification where the region of DNA amplified lies on either side of a known segment __________
Inverse – PCR
694 - Primer complementary to regions used in inverse PCR is _____________
3’ end of known region
695 - With respect to target DNA used in inverted PCR which of the following is not true?
Blunt ended segment
696 - The linear fragment used for inverted PCR has known ends _____________
TRUE
697 - With respect to RAPD which of the following is false?
Has inverted repeats
698 - Polymorphism in RAPD is observed because ______________
DNA used is from different chromosomes of different species
699 - RAPDs cannot be used for PCR amplification.
FALSE
700 - RAPDs are much more convenient markers than RFLPs.
TRUE
701 - The inheritance pattern of RAPD is _______________
Dominant
702 - RAPDs can be used to detect multiple alleles of a marker.
FALSE
703 - Who were the first to suggest that one strand of DNA might act as a template for the synthesis of its complementary strand?
Watson and crick
704 - Semiconservative nature of replication of eukaryotic chromosome was first demonstrated by _______
J. Herbert Taylor, Philip Wood and Walter Hughes on root tip cells of Vicia faba
705 - Watson and Crick’s suggestion of the complementary strand synthesis taking one of the parent strand as template was proposed in _________
1953
706 - Which of the following statements is true with respect to the DNA double helix?
The base pairs have opposite polarity
707 - Who, in which year showed firm enzymological proof that DNA alone functions as the template for the synthesis of new DNA strands?
Meselson and Stahl in 1958
708 - Replication of DNA ends are carried out by polymerase.
FALSE
709 - Which of the following regarding the basic mechanism of gene expression is correct?
RNA ―> cDNA ―> mRNA ―> protein
710 - Which of the following does not take part in gene expression?
Replication
711 - Multiple copies of RNA could be formed at the same time.
TRUE
712 - Amino acids prior to their incorporation into polypeptide must be attached to a special adaptor molecule. Who proved this and when?
Paul C. Zamecnic and Maholon B. Hoagland in 1957
713 - What is the condition required to observe B form of DNA?
High humidity
714 - What is the condition required to observe A form of DNA?
Low humidity
715 - How many bases are there in per turn of the B form of DNA?
10 bp
716 - Which of the following is not a character of A DNA?
Left handed helix
717 - How many bases are there in per turn of the A form of DNA?
11 bp
718 - Which of the following is not a character of B form of DNA?
Flat major groove
719 - In a right handed DNA the glycosidic bond is in syn configuration.
FALSE
720 - In the Z form of DNA the fundamental repeating unit is __________
Purine – pyrimidine tetra-nucleotide
721 - What is the factor responsible for the left-handed helical conformation in Z form of DNA?
Syn conformation at purine
722 - In higher salt concentration the DNA helix assumes the right-handed conformation.
FALSE
723 - According to the pairing concept of wobble hypothesis base “I†in the anticodon does not pair with?
G
724 - Which of the following is not a chain termination codon?
UGG
725 - The first amino acid added by the tRNA is added to the anticodon ____________
UAC
726 - The modification of which base gives rise to inosine?
Adenine
727 - The stop codon on the mRNA is read by __________
cRF1
728 - With respect to the genetic code reading frame which of the following is wrong?
Flexible reading frame
729 - The mitochondrial mRNA code for methionine is _____________
AUA
730 - The mitochondrial genome has _____________ stop codons.
4
731 - Fruitfly mitochondrial codes AGA and AGG codes for _____________
Serine
732 - With respect to the universal genetic code pick the odd one out.
UGG – Tryptophan
733 - Non – coding sequence in mRNA is known as __________
Intron
734 - Which of the following organisms have monocistronic DNA?
Bacteria
735 - Which of the following organisms have overlapping genes?
Virus
736 - Introns were first discovered in __________
1977
737 - Adenovirus is a useful model of studying gene expression because __________
High protein production
738 - Mouse β – globin gene has __________ introns.
2
739 - The amount of exon in the eukaryotic genome is higher than that of the introns.
FALSE
740 - The mRNA of which eukaryotic protein lacks introns?
Histone
741 - Introns are nothing more than genetic load in the eukaryotic genome.
FALSE
742 - Presence of introns facilitates the formation of several different mRNAs, thus increasing protein yield of different types but from same gene.
TRUE
743 - Eukaryotic ribosome is recruited to the mRNA by _____________
5’ capping
744 - After bounding to the mRNA eukaryotic ribosome scans the entire mRNA until it encounters a start codon.
TRUE
745 - The end of all tRNAs is ___________
5’ CCA 3’
746 - How many unusual bases are observed in a tRNA molecule?
5
747 - In pseudouridine the attachment of Uracil base to ribose through ___________ of uracil.
C at position 5
748 - Dihydrouridine is the result of oxidation of the uracil base.
FALSE
749 - How many loops are seen in the tRNA?
4
750 - How many double helix regions are observed in a tRNA molecule?
4
751 - The variable loop is found between the ___________
Anticodon loop and ΨU loop
752 - The 3 dimension structure of an adaptor molecule of translation is revealed to be ___________
L shaped
753 - Which of the following does not take part in stabilizing the cloverleaf model of the tRNA?
Ionic bond
754 - Enhancers that can function over very long distances known as ________________
Trans-acting enhancers
755 - Enhancers were first identified in __________
SV40 virus
756 - Enhancers in which of the following positions are unable to enhance the process of transcription?
Within the promoter site
757 - Immunoglobulin enhancers are active in which of the following cell types?
B lymphocytes
758 - Enhancers are a unit of multiple functional sequence elements that together regulates the expression of a gene.
TRUE
759 - The enhancers are gene specific regardless of the presence of insulators.
FALSE
760 - Transcriptional activators consist of __________ domains.
2
761 - The activation domain of activators recruits transcriptional factors to proper sites on the DNA.
FALSE
762 - How many mechanisms are present to enhance transcription by the enhancer molecules?
2
763 - Which of the following steps for the production of RNA is not regulated by enhancers?
Termination
764 - Pick the odd one out.
Introns
765 - Transposable elements are often found once in a gene and have a unique sequence for its own.
FALSE
766 - Junk DNA are also a type of transposable element that can jump from one location to another within the genome.
FALSE
767 - On the mechanism of the movement of transposable elements they are of ___________ types.
2
768 - The type of mutation that is imposed by transposons is ___________
Polar mutation
769 - Transposons were first discovered in ___________
Maize
770 - Transposons are able to move by ___________ mechanism(s).
2
771 - The transposons are more abundant than retrotransposons in higher eukaryotes.
FALSE
772 - Silencing of transposons cannot be achieved by which of the following mechanisms?
DNA phosphorylation
773 - Pick the odd one out.
Mu phage
774 - The splice site is found in __________
5’ end of intron
775 - During splicing which of the following sites is not recognized by the splicosome?
G-rich site
776 - The 3’ end of an intron is marked by __________
Acceptor site
777 - The highly conserved base at the branch point site is __________
A
778 - How many consensus sequences for splicing are found in an exon?
0
779 - To achieve splicing of an intron how many phosphodiester bonds are formed __________
2
780 - The first transesterification reaction between the branch point site and the 5’ splice site is a __________ reaction.
SN2
781 - The second transesterification reaction occurs between __________
The 5’ end of exon and the 3’ splice site
782 - The transesterification reaction is ATP independent.
TRUE
783 - In trans-splicing the excised intron forms a lariat structure.
FALSE
784 - Nonstop mediated decay is observed mostly in ____________
Animal
785 - Ski7 is known to recruit ____________ enzyme for mRNA degradation.
3’→5’ exonuclease
786 - Translation of an mRNA is the only way to proofread mRNAs.
TRUE
787 - Introns makes up about ____________ % of the total mRNA.
90
788 - The enzyme that degrades the mRNA recognizes ____________ bond of mRNA.
2’ – 5’
789 - The introns are degraded due to ____________
Unprotected ends
790 - How many ways of RNA degradation are found in eukaryotic cell?
2
791 - Nonsense mediated mRNA decay is proceeded due to the ____________
Absence of ORF
792 - Presence of premature stop codon triggers nonstop mediated decay.
FALSE
793 - Which of the following types of RNA is the most stable?
tRNA
794 - Which of the following is not a step to degrade mRNA?
Site-specific degradation
795 - The shorter half life of mRNAs is essential for the cells environmental adaptation in prokaryotes.
TRUE
796 - The half life of mRNA of both prokaryotic and eukaryotic cells is same.
FALSE
797 - mRNA for which of the following has a longer half life?
G protein
798 - Which of the following cannot be used for the separation of nucleic acids?
SDS – PAGE
799 - The polymerization of the gel used in PAGE occurs between polyacrylamide and ____________
N, N – methylene bisacrylamide
800 - If DNA is digested by endonucleases in four sites giving rise to fragments of which two are equal in length how many bands would be seen after electrophoresis?
4
801 - The fluorescent dye such Ethidium is used for visualizing DNA. How do ethidium binds to DNA?
Intercalated between the stacked bases
802 - Pulse field gel electrophoresis separates DNA molecules of size ___________
30 – 50 Kb
803 - Which of the following will migrate faster? The condition is the molecular weight of the following is equal.
Supercoiled circular DNA
804 - Agarose can be extracted from which of the following?
Gracilaria esculentus
805 - Electrophoresis cannot be used to separate _______________
Amino acid
806 - Which of the following is not a character of polyacrylamide gel?
Separate upto a few 100 bp of DNA
807 - Pulse field gel electrophoresis was developed by ____________
Schwartz and Cantor
808 - Histone H1 binds two DNA helices.
TRUE
809 - The distinct zig-zag appearance of the chromatin fibre is due to ____________
Histone H1
810 - With respect to Histone H1 DNA packaging which of the following is false?
H1 induce 10 nm fibre formation
811 - With respect to the solenoid model of nucleosome, which of the following is true?
Structure supported by X – ray diffraction
812 - What marks the difference between the solenoid and the zig-zag models of 30 nm fibres?
Linker DNA
813 - The histone tails stabilize the 30 nm fibre by interacting with adjacent nucleosomes.
TRUE
814 - Which of the following is not a characteristic of the nuclear scaffold?
Topoisomerase I
815 - Which histone molecule produces novel binding sites for protein components of the kinetochore?
CENP – A
816 - With respect to remodeling complex of nucleosome, which of the following is not true?
Does not require ATP
817 - The positioning of nucleosome is beneficial.
TRUE
818 - How many pre – rRNA transcript in eukaryotes are used to produce all the different mature rRNAs?
2
819 - In bacterial cell the 3 rRNAs 23S, 16S and 5S are derived from different transcripts.
FALSE
820 - Which one of the following rRNA undergoes least post-transcriptional processing?
5S
821 - The bacterial pre – rRNA undergo __________ cleavage.
2
822 - Which of the following types of processing is not used to prepare mature rRNA?
Splicing
823 - Each tRNA is produced from different transcripts.
FALSE
824 - The pre – tRNA involves cleavage by __________
RNase P
825 - RNase P is a ribozyme.
TRUE
826 - The common sequence for all tRNAs at their 3’ end is __________
CCA
827 - The 3’ CCA terminus is exceptionally added by the RNA polymerase during transcription.
FALSE
828 - Though unusual, pre – tRNA also undergo splicing. It is achieved by the help of __________
Endonuclease
829 - How many active sites are present in the DNA polymerase to catalyze the addition of the four dNTPs?
1
830 - How does the polymerase recognize the correct dNTP for an addition?
Ability of hydrogen bond formation
831 - DNA polymerase can distinguish between dNTPs and rNTPS due to ___________
Steric exclusion
832 - When we compare the structure of DNA polymerase to the structure of a body part, it resembles to _________________
Right hand
833 - With respect to the palm domain of the DNA polymerase which of the following is not its property?
Composed of α helix
834 - The two divalent metal ions of the active sites of DNA polymerase are major catalytic elements that bring about changes required for the joining of the dNTPs.
TRUE
835 - Mismatched DNA does not affect the rate of activity of DNA polymerase.
FALSE
836 - Which is the rate limiting step of DNA replication?
Binding of DNA polymerase to the primer:template junction
837 - RNA genomes were first discovered in ___________ viruses.
Plant
838 - The initial hypothesis of RNA provirus was proposed by __________ in 1960s.
Howard Temin
839 - Reverse transcription is an important phenomenon for eukaryotic cells.
TRUE
840 - The virus on which the first experiment performed by Howard Temin was __________
Rous Sarcoma Virus
841 - The viral genome contains which of the following characteristic sequences?
LTRs
842 - The integration of viral DNA into the host DNA is promoted by the host integrase enzyme.
FALSE
843 - Which of the following is not a function of reverse transcriptase?
Exonuclease
844 - Reverse transcription has a high error rate.
TRUE
845 - What will be the transcription product of 3’….AUCCGAGCUAAC….5’ by reverse transcriptase?
3’….GTTAGCTCGGAT….5’
846 - Reverse transcription is a very important tool in modern molecular biology techniques.
TRUE
847 - Which of the following is not a type of post translational modification?
Protein folding
848 - Proteolytic modifications of the polypeptide are an important process in the mechanism for protein sorting and transport.
TRUE
849 - The amino acid is the signal sequence in any polypeptide chain for ____________
Proteolytic site
850 - The first step in protein targeting is ___________
Translocation to ER
851 - How many Proteolytic cleavages produce mature insulin?
2
852 - Glycosylation is the addition of ___________ to the protein.
Carbohydrate
853 - In the N-linked glycoprotein, the carbohydrates are attached to which of the following bases?
Asparagine
854 - In O-linked glycoproteins, the carbohydrates may be attached to how many amino acids?
2
855 - Initiation of glycosylation occurs in the Golgi body.
FALSE
856 - How many types of modification are possible in eukaryotes by addition of lipids?
4
857 - Prenylation adds prenyl groups to the ___________ amino acid residues.
Cystine
858 - Frame shift mutation can increase or decrease the length of a polypeptide.
TRUE
859 - If the insertions of three nucleotides occur in a consecutive manner it causes which of the following type of mutation?
Frame shift mutation
860 - Which macromolecule is not abundantly found though being of critical importance for biological mechanisms?
Lipids
861 - Which of the following is wrongly paired?
Nucleic acid – hydrogen bond
862 - With respect to nucleosides which of the following is paired correctly?
Pyrimidine – Uridine, Cytidine
863 - Which of the following is not a component of the nucleic acid backbone?
Nucleotide
864 - According to Chargaff’s rule the two strands of DNA has ___________
Different molecular weight
865 - In one strand of a double stranded DNA the rate of occurrence of A is 3 times C in consecutive 10 bases. So how many G will be there in 100 base pairs of a DNA duplex?[Consider G=T in one strand].
40
866 - In a diploid organism with 30,000 bases haploid genome contains 23% A residues. What is the number of G residues in the genome of this organism?
16200
867 - Which of the following is not a characteristic of nucleotide bases?
Aliphatic
868 - Which of the following factors do not provide to the separation of DNA fragments during electrophoresis?
Ethidium bromide
869 - Which one of the following is not a function of a nucleotide?
Receptors
870 - Which of the following is the genetically engineered insulin?
Humulin
871 - Genetically manufactured GH is not effective for?
Infections
872 - Active insulin consists of how many polypeptide chains?
2
873 - The first successful active insulin was synthesized in __________
1977
874 - The Insulin A vector does not contain __________
B chain
875 - Pick the odd one out.
Insulin
876 - Genetically engineered somatotropin is formed by introducing DNA fragment from the genome to the plasmid.
FALSE
877 - Which one of the following was first expressed as a fusion protein?
Somatostatin
878 - How many classes of interferons are found in humans?
3
879 - Synthesis of hGH is an inducer dependent process.
TRUE
880 - The major enzyme required for the production of a chimera molecule is __________
Polymerase
881 - The subunit vaccine for hepatitis B is created against __________
Surface protein
882 - Pick the odd one out.
Antibodies
883 - Monoclonal antibodies are produced by __________
Hybridoma technology
884 - Double-stranded structure of nucleic acid is the basic requirement for palindromic sequences.
TRUE
885 - Which of the following words represents a palindrome?
MADAM
886 - Which of the following will form a palindromic sequence?
ATTGCAAT
887 - Which of the following is affected by palindromic sequences?
Methylation site
888 - Palindromic sequences play a very important role in gene manipulation.
TRUE
889 - Which of the following palindromes is not a restriction site?
TACGTA
890 - Molecular cutters do not recognize the palindromic sequence.
FALSE
891 - Which of the following is an example of an inverted repeat?
ATCGNNNNCGAT
892 - Inverted repeat have a number of biological functions. Which of the following is a biological function of an inverted repeat?
Diseases
893 - Most commonly known hairpin structures are found in _____________
tRNA
894 - Which of the following does not promote stability in stem-loop structure?
A : U base pairing
895 - What is the minimum number of bases required for loop stability?
3
896 - Which of the following does not contain a stem-loop structure?
rRNA
897 - Which of the following is not true about nucleotides?
Non enzymatic molecules
898 - The nitrogenous base is covalently linked to the _________ carbon of the pentose sugar.
C1
899 - In which carbon do the deoxyribonucleotides lack an –OH molecule?
C2
900 - Which of the following is not a part of a nucleotide?
Hydrogen bond
901 - Which of the following is not a part of a nucleoside?
Phosphate
902 - The linkage between the sugar and the base is a covalent linkage.
TRUE
903 - Which of the following is not a nucleotide?
TMP
904 - Purines and pyrimidines form glycosidic linkage with the purines and pyrimidines at the N6 position.
FALSE
905 - Who of the following was not one of the scientists explaining the replicon model?
Arthur Kornberg
906 - The replicon model was first explained in the year ____________
1963
907 - The eukaryotic chromosome has a single replicon.
FALSE
908 - The replicon model comprises of an initiator and _______________
Replicator
909 - Replicator is the synonym for origin of replication.
FALSE
910 - The initiator protein binds to a segment ____________ of the replicator sequence.
Within
911 - Binding of the Dna A protein to the DNA is energy dependent.
TRUE
912 - Assembly of how many proteins make up the origin replication complex (ORC) in eukaryotes?
6
913 - Which of the following proteins is not recruited by Dna A protein?
SSB protein
914 - For the translation to be initiated which of the following does not occur?
Addition of charged tRNA to the A site
915 - Changing the positioning of the ribosome leads to the synthesis of different proteins.
TRUE
916 - What kind of interactions results in the binding of mRNA and the ribosome?
Hydrogen bonding
917 - In case of prokaryotes the first tRNA enters the ribosome in the ____________
P site
918 - The initiation of translation requires a special type of tRNA to bind to the ORF of the mRNA.
TRUE
919 - The first amino acid to be incorporated in the prokaryotic polypeptide is ____________
N-formyl methionine
920 - Deformylase has a crucial role to play in the formation of mature polypeptide chains in prokaryotes.
TRUE
921 - How many translation initiation factors work hand in hand to initiate prokaryotic translation?
3
922 - Which of the following is a GTPase?
IF2
923 - Which of the following is not the function of IF3?
Helps associate the large and small subunits during translation
924 - When the large and small subunit of ribosome associate which of the following is not found within the complex?
IF3
925 - Semiconservative nature of replication of eukaryotic chromosome was first demonstrated by _______________
J. Herbert Taylor, Philip Wood and Walter Hughes on root tip cells of Vicia faba
926 - Pick the correct pair with respect to primers used in DNA replication.
RNA primer- for both prokaryotes and eukaryotes
927 - Which of the following is correctly matched with its subsequent role?
DnaA protein- responsible for “melting†of the DNA double helix during replication
928 - Replication fork is the junction between the two ___________
Newly separated DNA strands and the unreplicated DNA
929 - Which of the following does not affect DNA replication?
SSB protein
930 - Who was the first person to analyse the process of replication and on which organism?
John Cairns: E. coli
931 - In the case of a circular DNA synthesis how many replication forks are observed?
2
932 - Primer synthesis short stretches of DNA for replication.
FALSE
933 - Which of the following is not used for degrading RNA from RNA:DNA hybrid in replication?
RNase A
934 - The gaps formed by the hydrolyzing the RNA from RNA:DNA hybrid is filled by DNA polymerase I and the nicks are ligated by T4 ligase.
FALSE
935 - Which of the following is correctly matched with its subsequent role?
DnaA protein- responsible for “melting†of the DNA double helix during replication
936 - The first X-ray diffraction patterns of DNA were taken in 1938 by ___________
William Asbury
937 - In early 1950s high quality X-ray diffraction photographs of DNA suggesting the DNA being double helix and composed of two nucleotide strands. Who took those photographs?
Rosalind Franklin and Maurice Wilkins
938 - In 1952, an unambiguous established work in the laboratory of Alexander Todd led to the discovery of _____________
3’-5’ phosphodiester linkage regularly links the nucleotides of DNA
939 - What should be the complementary strand of 3’….ATGGCTTGA….5’?
5’….TACCGAACT….3’
940 - The hydrogen bonds formed during A and T bonding occurs between C6NH2 of A and __________
C4O of T
941 - In a DNA double helix the bases are held together by hydrogen bonds. These hydrogen bonds are _________
Non-covalent bonds
942 - It is easy to break the bond between A and T than in between G and C.
TRUE
943 - With respect to the importance of hydrogen bonding and DNA double helix stability, which of the following statements is false?
Decreases the entropy
944 - In the late 1970s non double helical form of DNA was also suggested but was discarded on the basis of certain factors. Which of the following is not a factor responsible?
Nuclein
945 - Levene investigated and found that the nucleic acid is composed of poly-nucleotides and each nucleotide is composed of one base, a sugar molecule and a phosphate. This was performed on the genome of________________
Yeast
946 - In case of transcription which is the rate limiting step?
Binding of RNA polymerase
947 - The site where repressor binds the DNA is the ______________
Operator
948 - Recruitment of RNA polymerase to the promoter is a ___________
Cooperative binding
949 - The proteins of which of the following genes are regularly needed for cellular activity?
Housekeeping genes
950 - Which of the following is not an example of allosteric regulation?
Inactivation of nitrogenase by ADP ribosylation
951 - Operons are ___________
found in some eukaryotes
952 - Choose the correct pair among the following.
The DNA sequence that codes for a protein – structural gene
953 - Which of the following is not present in the β-galactosidase structural gene and thus is not transcribed by the same promoter?
Lac I
954 - Glucose, as the carbon source, is the first choice by bacteria even if other sugars are available. The mechanism behind this selectivity is ___________
Catabolite repression
955 - The lac operon is regulated by cAMP by ___________
Binding to catabolite activator protein
956 - Tryptophan operon in E. coli is a repressible operon.
TRUE
957 - Which of the following is true about tryptophan operon?
The Trp repressor binds to the tryptophan
958 - The expression of the tryptophan operon is independent of the availability of tryptophan in culture media.
FALSE
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