InterviewSolution
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InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 51. |
Jacob and Monod studied lactose metabolism in E. coli and proposed operon concept which is applicable for all :A. All prokaryotesB. All prokaryotes and some eukaryotesC. All prokaryotes and all eukaryotesD. All prokaryotes and some protozoans |
| Answer» Correct Answer - A | |
| 52. |
E. coli cell with a mutated Z gene of the lac operon cannot grow in medium containing only lactose as the source of energy because:A. In the presence of glucose, E. coli cells do not utilise lactoseB. They cannot transport lactose from the medium into the cellC. The lac operon is constitutively active in these cellsD. They cannot synthesis functional `Beta`-galactosidase |
| Answer» Correct Answer - D | |
| 53. |
Consider the following statements `:` Assertion (A) `:` Amber codon is a termination codon . Reason (R ) `:` If in a m-RNA, a termination codon is present, the protein synthesis stops abruptly whether the protein synthesis is complete or not. Now select you answer from code given below `:`A. Both Assertion and Reason are true and the Reason is a correct explanation of the AssertionB. Both Assertion and Reason are true and the Reason is not the correct explanation of the AssertionC. Assertion is true, but the Reason is falseD. Assertion is false, but the Reason are false |
| Answer» Correct Answer - A | |
| 54. |
During chain elongation, peptide bond is formed between carboxyl group of first and amino group of second amino acid byA. Peptidyl transferaseB. DNA ligaseC. Taq polymeraseD. Helicase |
| Answer» Correct Answer - A | |
| 55. |
During transcription holoenzyme RNA polymerase binds to a DNA sequence and the DNA assumes a saddle like structure at that point. What is that sequence called ?A. CAAT boxB. CGTT boxC. AAAT boxD. TATA box |
| Answer» Correct Answer - D | |
| 56. |
During transcription holoenzyme RNA polymerase binds to a DNA sequence and the DNA assumes a saddle like structure at that point. What is that sequence called ?A. TTAAB. AATTC. CACCD. TATA |
| Answer» Correct Answer - D | |
| 57. |
What is correct gene expression pathway ?A. Gene-mRNA-Transcription-Translation-ProteinB. Transcription-Gene-Translation-mRNA-ProteinC. Gene-Transcription-mRNA -Translation-proteinD. Gene-Translation-mRNA-Transcription-Protein |
| Answer» Correct Answer - C | |
| 58. |
During translation, the activation of amino acids I.Takes place through their carboxyl groups II.Continues until a termination codon reaches the ribosome III. Is catalysed by its own activating enzyme called aminoacyl tRNA synthetase IV. Involves movement of second amino acid tRNA complex from A-site to P-siteA. I and IIB. II and IIIC. I and IIID. II and IV |
| Answer» Correct Answer - C | |
| 59. |
Select the incorrect statement (a) Six codons do not code for any amino acid (b) Codon reading of mRNA is contiguous (c) Three codons function as stop codons (d) Initiator codon AUG codes for methionineA. I,II and IVB. I, II and IIIC. II, III and IVD. Only I |
| Answer» Correct Answer - D | |
| 60. |
If following is the sequence of nucleotides in mRNA , predict the sequence of amino acids coded by it AUG UUU UUC UUC UUU UUU UUCA. Met-Phe-Phe-Phe-Phe-Phe-PheB. Met-Phe-Leu-Leu-Phe-Phe-LeuC. Ser-Leu-Phe-Leu-Phe-Leu-PheD. Arg-Leu-Leu-Leu-Leu-Leu |
| Answer» Correct Answer - A | |
| 61. |
Some amino acids are coded by more than one codonA. UnambiguousB. DegenerateC. UniversalD. Initiator |
| Answer» Correct Answer - B | |
| 62. |
Assertion (A) `:` Replication and transcription occur in the nucleus but translation occurs in the cytoplasm. Reason (R ) `:` m-RNA is transferred from the nucleus into the cytoplasm where ribosomes and amino acids are available for protein synthesis.A. Both Assertion and Reason are true and the Reason is a correct explanation of the AssertionB. Both Assertion and Reason are true and the Reason is not the correct explanation of the AssertionC. Assertion is true, but the Reason is falseD. Assertion is false, but the Reason are false |
| Answer» Correct Answer - B | |
| 63. |
In 125 amino acid sequence if the codon of 25th amino acid is mutated to UAA, thenA. A polypeptide of 24 amino acids is formedB. A polypeptide of 124 amino acids id formedC. No polypeptide are formedD. A polypeptide of 25 amino acids is formed |
| Answer» Correct Answer - A | |
| 64. |
Which one of the following pairs of codons is correctly matched with their function or the signal for the particular amino acid ?A. GUU, GCU - AlanineB. UAG,UGA - StopC. AUG, ACG - Start/MethionineD. UUA,UCA - Leucine |
| Answer» Correct Answer - B | |
| 65. |
Which one of the following pairs is correctly matched with regard to the codon and the amino acid coded by it `?`A. UUA- ValineB. AAA-lysineC. AUG- cysteineD. CCC-alanine |
| Answer» Correct Answer - B | |
| 66. |
What does 'lac' refer to in what we call the lac operon ?A. LactoseB. LactaseC. Lac insectD. The number 100000 |
| Answer» Correct Answer - A | |
| 67. |
mRNA is also known asA. informational RNAB. template RNAC. messenger RNAD. All of these |
| Answer» Correct Answer - D | |
| 68. |
The bond present between the sugar and phosphate group of DNA isA. hydrogen bondsB. ionic bondsC. phosphodiester bondsD. glycosidic bonds |
| Answer» Correct Answer - C | |
| 69. |
Out of 64 codons, the number of codons with GGGisA. 1B. 2C. 4D. 6 |
| Answer» Correct Answer - A | |
| 70. |
Anticodon is present onA. rRNAB. tRNAC. mtDNAD. mRNA i |
| Answer» Correct Answer - D | |
| 71. |
Which of the following is not true for an anticodon?A. It consists of three nucleotidesB. It is the basic unit of the genetic codeC. It extends from one end of a tRNA moleculeD. It may pair with more than one codon , especially if it has the base inosine in its third position |
| Answer» Correct Answer - B | |
| 72. |
In E. coli, tryptophan switches off the trp operon byA. inactivating the repressorB. inactivating the gene for the first enzyme in the pathway by feedback inhibitionC. binding to the repressor and increasing the latters affinity for the operatorD. binding to the operator |
| Answer» Correct Answer - C | |
| 73. |
During transcription, the site of DNA molecule at which RNA polymerase binds is calledA. promoterB. regulatorC. receptorD. enhancer |
| Answer» Correct Answer - A | |
| 74. |
Which conserved motifs are found in E. coli genes ?A. TATA boxB. CAAT boxC. Probnow boxD. All of these |
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Answer» Correct Answer - A TATA box conserved motif is found in E.coli genes. |
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| 75. |
Process of reverse transcription was discovered byA. Temin and BaltimoreB. Watson and CrickC. Alfred HersheyD. None of these |
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Answer» Correct Answer - A Temin and Baltimore (1972) discovered the process of reverse transcription |
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| 76. |
which of the following amino acid codon was used by khorana?A. SerineB. TryptophanC. AlanineD. Valine |
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Answer» Correct Answer - A By using synthetic DNA khorana et. Al prepared chains of polyribonuclotides with known repeated sequence of two or three nucleotides as poly CUC UCU CUC UCU Hence two codons repeated alternately . This dictates the formation of polypeptides chain having two amino acid alternatively i.e serine and lecine |
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| 77. |
Which one of the following statements regarding lac operon is correct?A. Lac operon is inducible systemB. Lac operon is repressible systemC. Lac operon of E.coli contain four structural genesD. None of the above |
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Answer» Correct Answer - A Lac operon is an inducible operon in which the presence of key metabolic substance i.e lactose indices transcription of structural genes lac person consist of three structural genes Tryptophan operon is a repressible operon where repressor is inactive and it becomes active as DNA binding proteins complexed with corepressor |
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| 78. |
Which amino acids can be used for synthesis of haemoglobinA. Glutamic acidB. ValineC. SerineD. All of these |
| Answer» Correct Answer - D | |
| 79. |
The sailent feature of genetic code isA. one codon codes for only one amino acidB. some amino acids are coded by more than one codonsC. a codon is made of three nucleotidesD. All of the above |
| Answer» Correct Answer - D | |
| 80. |
If the codon GGU is reversed, the resulting codon will code for this amino acidA. TyrB. TrpC. LeuD. Thr |
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Answer» Correct Answer - B If the codon GGU is reversed the resulting codon will be UGG that codes for trp (Tryptophan), GGU codes for Gly (Glycine) |
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| 81. |
Identify the correct pair of combinations. I. `.^(14)C-` Distinction between PSI and PS II II. `.^(14)N-` Semiconservative replication of DNA III. `.^(35)S-` Polypeptide synthesis IV. `.^(32)P-` Identification of chemical nature of geneic materialA. II and IIIB. II and IVC. I and IID. I and III |
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Answer» Correct Answer - A `.^(15)N` isotope was used by meselson and Strahl to experimentally determine the semiconservation method of DNA replication `S^(35)` isotopes takes part in protein synthesis that why also called as protoplasmic element |
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| 82. |
Assume that the occurrence of nitrogen bases in adjacent positions in a DNA strand is random. Identify the minimum number of nucleotides in a DNA strand where GAAT can occur once on the basis of probabilityA. 512B. 256C. 4096D. 1024 |
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Answer» Correct Answer - B On this basis balance the probability of minimum number of nucleotides in Singlet code = (4) `xx` 1 = 4 doublet code = 4`xx`4= 16 Triplet code = 4`xx`4`xx`4= 64 here the code given in quadruplet (GAAT) so it will be 4`xx` 4 `xx` 4 `xx` 4 = 256 number of nucleotides |
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| 83. |
Statement A : The primary transcript produced in eukaryotic is translated without undergoing any modification or processing. Statement B: The hn-RNA in humans has exons and introns.A. Both the statements A and B are correctB. Both the statements A and B are incorrectC. Statement B is correct, and Statament A is IncorrectD. Statement A is correct, and statement B is incorrect |
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Answer» Correct Answer - C The primary transcript contains both introns and exons and are non-functional . Therefore they undergo a process of splicing for removing introns and joining exons in the proper order. It will further undergo post transcriptional modifications I.e capping and tailing After which a fully processed hnRNA is now called mRNA is transported out of the nucleus for translation |
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| 84. |
RNA and DNA were artificially synthesised in vitro byA. Ochoa and NirenbergB. Ochoa and KornbergC.D. kornberg and Nirenberg |
| Answer» Correct Answer - D | |
| 85. |
cDNA is formed byA. TranscriptionB. ReplicationC. Reverse transcriptionD. Translation |
| Answer» Correct Answer - C | |
| 86. |
The scientist who was awarded Nobel prize in 1959 for in vitro synthesis of ployribonucleotide :-A. TatumB. DarwinC. KornbergD. Khorana |
| Answer» Correct Answer - C | |
| 87. |
The isotopes used by HerA. `.^(59)"Iron" and .^(45)"Nitrogen"`B. `.^(131)"Iodien" and .^(45)"Calcium"`C. `.^(15)"Nitrogen" and .^(14)"Carbon"`D. `.^(35)"Sulphur" and .^(32)"Phosphorus"` |
| Answer» Correct Answer - C | |
| 88. |
If a virus is grown with radioactive S it will show in radioactivity inA. DNAB. RNAC. proteinD. All of these |
| Answer» Correct Answer - B | |
| 89. |
Which was the first genetic material to be originitedA. DNAB. proteinC. RNAD. DNA + RNA |
| Answer» Correct Answer - A | |
| 90. |
Select the correct statement about the structure gene in a transcription unit in bacteria .A. The structural gene in a transcription unit in bacteria could be said as polycistronicB. In bacteria , the structural gene has mRNA that can encode more than one polypeptide separately with in could be said as monocistronicC. All of the aboveD. |
| Answer» Correct Answer - C | |
| 91. |
What is the difference between RNA and DNA?A. BaseB. SugarC. PhosphateD. Both (a) and (b) |
| Answer» Correct Answer - C | |
| 92. |
Assertion Non-sense codons are responsible for terminating peptide chain Reason Non-sense codons are not recognised by tRNAA. Both Assertion and Reason are true and the Reason is a correct explanation of the AssertionB. Both Assertion and Reason are true and the Reason is not the correct explanation of the AssertionC. Assertion is true, but the Reason is falseD. Assertion is false, but the Reason are false |
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Answer» Correct Answer - A There are three codons ,i.e UAA, UAG,UGA, which are responsible for the termination of a polypeptide chain beacause these triplets do not recognise by tRNA during the process of translation. |
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| 93. |
Assertion A non-overlapping code means that a base in mRNA is not used for different codons Reason In translating mRNA molecules, the codons do not overlap but are read sequentiallyA. Both Assertion and Reason are true and the Reason is a correct explanation of the AssertionB. Both Assertion and Reason are true and the Reason is not the correct explanation of the AssertionC. Assertion is true, but the Reason is falseD. Assertion is false, but the Reason are false |
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Answer» Correct Answer - B The genetic code is triplet, degenerate,commaless, non ambiguous universal and non-overlaping . The non-overlaping code means that a base in mRNA is not used for two different codons. For example , AUG AGC GCA is not read as AUG GAG (an overlap of two bases) or CGA GCA CA (overlapping of one base |
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| 94. |
Which of the following sequence is found in Rous sarcoma virusA. DNA-DNA-ProteinB. RNA-DNA-RNA-ProteinC. RNA-RNA-ProteinD. DNA-RNA-Protein |
| Answer» Correct Answer - D | |
| 95. |
Which of the following steps in transcription is catalysed by RNA polymerase?A. InitiationB. ElongationC. TerminationD. All of these |
| Answer» Correct Answer - B | |
| 96. |
Whose experiments cracked the DNA and discobered unequivocally that a genetic code is a "triplet" :-A. Nirenberg and MathaeiB. Hershey and ChaseC. Morgan and StrulevantD. Beadle and tatum |
| Answer» Correct Answer - B | |
| 97. |
The properties of genetic material isA. It should express in parent but not in offspringB. It should replicate itselfC. It should not change at allD. All of the above |
| Answer» Correct Answer - C | |
| 98. |
The genetic trnsformation experiments on Diplococcus pneumoniae gave first undoubted evidence that `:`A. DNA is the genetic materialB. DNA is made up of nucleotidesC. Chromosomes are made of DNAD. RNA is synthesised on a DNA template |
| Answer» Correct Answer - A | |
| 99. |
The transformation experiment on Diplococcus pneumoniae was performed byA. Colin MacleodB. T AveryC. Frederick GriffithD. Hershey and chase |
| Answer» Correct Answer - C | |
| 100. |
Assertion (A) Transcription unit is often monocistronic in eukaryotes and polycistronic in prokaryotes Reason (`R`) Exons do not appear in mature RNA, introns appear is mature RNA.A. A and R are true and R is correct explanation of AB. A and R are true, but R is not correct explanation of AC. A is true, but R is falseD. A is false, but R is true |
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Answer» Correct Answer - C During the RNA splicing introns are removed and exons are joined to form a contiguous coding. This make mature mRNA ready for translation Eukaryotic mRNA moleculea are monocistonic containing the coding sequence only for one polypeptide In prokaryotes an individual bacterial mRNA molecules are polycistronic having transcripts of several genes |
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