1116 + Interview Questions in BIOTECHNOLOGY IN GENERAL AWARENESS Page 4 InterviewSolution

151.	a. What are “molecular scissors”? Give one example.b. Explain their role in recombinant DNA technology.ORWhy are molecular scissors so called? Write their use in biotechnology.
Answer» a. The restriction endonucleases are called molecular scissors, as they cut the DNA segments at particular locations, *e.g.,* EcoRI. b. The restriction enzymes cut the DNA strands a little away from the centre of the palindromic sites, but between the same two bases on the opposite strands. This leaves single stranded portions with overhanging stretches called sticky ends on each strand as they form hydrogen bonds with their complementary cut counterparts. This stickiness at the ends facilitates the action of the enzyme DNA ligase.

151.

a. What are “molecular scissors”? Give one example.b. Explain their role in recombinant DNA technology.ORWhy are molecular scissors so called? Write their use in biotechnology.

Answer»

a. The restriction endonucleases are called molecular scissors, as they cut the DNA segments at particular locations, e.g., EcoRI.

b. The restriction enzymes cut the DNA strands a little away from the centre of the palindromic sites, but between the same two bases on the opposite strands. This leaves single stranded portions with overhanging stretches called sticky ends on each strand as they form hydrogen bonds with their complementary cut counterparts. This stickiness at the ends facilitates the action of the enzyme DNA ligase.

152.	What are molecular scissors? Why are they so called?
Answer» The enzyme restriction endonucleases are called molecular scissors because they can cut the DNA molecule at a specific point

153.	Some enzymes are considered as molecular scissors. in genetic engenrring. What is the name assigned to such enzymes?
Answer» Restriction Enzymes.

154.	The thermostable enzyme , 'Taq' and 'Pfu', is isolated from thermophilic bacteria are :A. RNA polymeraseB. DNA polymerasesC. Restriction endonculeasesD. DNA ligase
Answer» Correct Answer - B

155.	In the PCR technology the DNA segment is replicated over a billion times. This repeated replications catalyzed by the enzymeA. DNA polymerasesB. Taq polymeraseC. DNA dependent RNA polymeraseD. Primase
Answer» Correct Answer - B

156.	The term 'molecular scissors' generally refers toA. DNA polymerasesB. RNA polymerasesC. Restriction endonculeasesD. DNA ligase
Answer» Correct Answer - C

157.	The terms "antibiotic " was coined by:A. Edward JennerB. Louis PasteurC. Selman waksmanD. Alexander Fleming
Answer» Correct Answer - C

158.	Widely used tool in genetic engineering of crop plant involves :A. MicroinjectionB. Protoplast fusionC. Transposon mediationD. Agrobacterium mediation
Answer» Correct Answer - D

159.	Bacterial artifical chromosomes is based onA. F-factorB. R-factorC. R-plasmidsD. epigenetic factor
Answer» Correct Answer - a

160.	Name the following :Recombinant protein used in the treatment of haemophilia B.
Answer» Recombinant protein used in the treatment of haemophilia B is Factor IX

161.	Is there any difference between recombinant DNA and recombinant protein? Support your answer.
Answer» rDNA is the plasmid vector containing the foreign DNA whereas recombinant protein is the product of transgenic gene in the host body or cell.

163.	In recombinant DNA technology, the term vector refers toA. the enzyme that cuts DNA into restriction fragmentsB. the sticky end of a DNA fragmentC. a plasmid used to transfer DNA into a living cellD. a DNA fragment which carries only ori gene
Answer» Correct Answer - C The DNA used as a carrier for transferring a fragment of forign DNA into a suitable host is called vehicle DNA or cloning vector or gene carrier. When desired gene is introduced into a vector, recombinant DNA is formed. Vectors may be plasmids, bacteriophages, cosmids, phagemids, Yeast Artificial Chromosomes (YACs), Bacterial Artificial Chromosomes (BACs), transposons, viruses. etc.

164.	Restriction enzymes present in the cloning site of a vector should not have more than one recognition site. Comment.
Answer» If the restriction enzymes have more than one recognition site in a vector, then the vector itself will get fragmented on treatment with the restriction enzyme.

165.	Which of the following is the correct recognition sequence of restriction enzyme hind III. (a) 5′ —A-A-G-C-T-T— 3′ 3′ —T-T-C-G-A-A—5′ (b) 5′ — G-A-A-T-T-C—3′ 3′ — C-T-T-A-A-G—5'(c) 5′ — C-G-A-T-T-C—3′ 3′ — G-C-T-A-A-G—5′ (d) 5′ — G-G-C-C—3′ 3′ — C-C-G-G—5′
Answer» Correct answer is (a) 5’ —A-A-G-C-T-T—3’ 3’ —T-T-C-G-A-A—5’

166.	Recombinant protein ……….. is used to dissolve blood clots present in the body. (a) insulin (b) tissue plasminogen activator (c) relaxin (d) erythropoietin
Answer» Correct answer is (b) tissue plasminogen activator

167.	Give the role of Ca++ ions in the transfer of recombinant vector into bacterial host cell.
Answer» Ca⁺⁺ ions promotes binding of plasmid DNA to lipo polysaccharides on bacterial cell surface. Then plasmid can enter the cell on heat shock.

168.	In recombinant DNA technology, the term vector refers toA. the enzyme that cuts DNA into restriction fragmentsB. the sticky end of a DNA fragmentC. a plasmid used to transfer DNA into a living cellD. a DNA probe used to identify a particular gene
Answer» Correct Answer - C

169.	Recognition sequence of restriction enzymes are generally ………….. nucleotide long. (a) 2 to 4 (b) 4 to 8(c) 8 to 10 (d) 14 to 18
Answer» Correct answer is (b) 4 to 8

170.	Which cells from Langerhans of pancreas do produce a peptide hormone insulin?
Answer» cells of islets of Langerhans of a peptide hormone insulin.

171.	Name the vector which is used in production of human insulin through recombinant DNA technology.
Answer» plasmid Bolivar and Rodriguez (PBR 322)

172.	A genetically engineered microbe utilized for cleaning oil spills is:A. Bacillus subtilisB. Escherichia coliC. Pseudomonas putidaD. Agrobacterium tumefaciens
Answer» Correct Answer - C Genetically engineered bacterium pseudomonas putida is used for scavenging of oil spills by digesting hydrocarbons of crude oil. A. M. Chakarabarty in 1974 created and patented "superbug" which had an increased capability of hydrocarbon degradation.

173.	The strategy used to prevent the nematode infection in the roots of tobacoo plant in called:A. Bt toxin geneB. Gene mutationC. RNA interferneceD. Use of agrochemicals
Answer» Correct Answer - C

174.	First hormone prepared artificially by culturing bacteria was:A. insulinB. oxytocinC. adrenalineD. somatotropin
Answer» Correct Answer - A

176.	What percent of world population is affected by iron deficiency?
Answer» 30% of the population is affected by iron deficiency.

177.	What causes softening of tomatoes during ripening?
Answer» The enzyme polygalacturonase in tomato, breaks down pectin in the middle lamella of cell wall. This results in softening of fruits J during ripening.

Explore topic-wise InterviewSolutions in .

a. What are “molecular scissors”? Give one example.b. Explain their role in recombinant DNA technology.ORWhy are molecular scissors so called? Write their use in biotechnology.

What are molecular scissors? Why are they so called?

Some enzymes are considered as molecular scissors. in genetic engenrring. What is the name assigned to such enzymes?

The thermostable enzyme , 'Taq' and 'Pfu', is isolated from thermophilic bacteria are :A. RNA polymeraseB. DNA polymerasesC. Restriction endonculeasesD. DNA ligase

In the PCR technology the DNA segment is replicated over a billion times. This repeated replications catalyzed by the enzymeA. DNA polymerasesB. Taq polymeraseC. DNA dependent RNA polymeraseD. Primase

The term 'molecular scissors' generally refers toA. DNA polymerasesB. RNA polymerasesC. Restriction endonculeasesD. DNA ligase

The terms "antibiotic " was coined by:A. Edward JennerB. Louis PasteurC. Selman waksmanD. Alexander Fleming

Widely used tool in genetic engineering of crop plant involves :A. MicroinjectionB. Protoplast fusionC. Transposon mediationD. Agrobacterium mediation

Bacterial artifical chromosomes is based onA. F-factorB. R-factorC. R-plasmidsD. epigenetic factor

Name the following :Recombinant protein used in the treatment of haemophilia B.

Is there any difference between recombinant DNA and recombinant protein? Support your answer.

Name the following :Recombinant protein used in the treatment of haemophilia A.

In recombinant DNA technology, the term vector refers toA. the enzyme that cuts DNA into restriction fragmentsB. the sticky end of a DNA fragmentC. a plasmid used to transfer DNA into a living cellD. a DNA fragment which carries only ori gene

Restriction enzymes present in the cloning site of a vector should not have more than one recognition site. Comment.

Recombinant protein ……….. is used to dissolve blood clots present in the body. (a) insulin (b) tissue plasminogen activator (c) relaxin (d) erythropoietin

Give the role of Ca++ ions in the transfer of recombinant vector into bacterial host cell.

In recombinant DNA technology, the term vector refers toA. the enzyme that cuts DNA into restriction fragmentsB. the sticky end of a DNA fragmentC. a plasmid used to transfer DNA into a living cellD. a DNA probe used to identify a particular gene

Recognition sequence of restriction enzymes are generally ………….. nucleotide long. (a) 2 to 4 (b) 4 to 8(c) 8 to 10 (d) 14 to 18

Which cells from Langerhans of pancreas do produce a peptide hormone insulin?

Name the vector which is used in production of human insulin through recombinant DNA technology.

A genetically engineered microbe utilized for cleaning oil spills is:A. Bacillus subtilisB. Escherichia coliC. Pseudomonas putidaD. Agrobacterium tumefaciens

The strategy used to prevent the nematode infection in the roots of tobacoo plant in called:A. Bt toxin geneB. Gene mutationC. RNA interferneceD. Use of agrochemicals

First hormone prepared artificially by culturing bacteria was:A. insulinB. oxytocinC. adrenalineD. somatotropin

(a) Mention the cause and the body system affected by ADA deficiency in humans. (b) Name the vector used for transferring ADA-DNA into the recipient cells in humans. Name the recipient cells in humans. Name the recipient cells.

What percent of world population is affected by iron deficiency?

What causes softening of tomatoes during ripening?

The role of DNA ligase in the construction of a recombinant DNA molecule is :A. Formation of phosphodiester bond between two DNA fragmentsB. Formation of hydrogen bonds between sticky ends of DNA fragmentsC. Ligation of all purine and pyrimidine basesD. All of the above

The role of DNA ligase in the construction of a recmobinant DNA molecule isA. Formation of phosphodiester bond between two DNA fragmentsB. Formation of hydrogen bonds between sticky ends of DNA fragmentsC. Ligation of all purine and pyrimidine basesD. None of the these

Construction of first recombinant DNA was done by using plasmid ofA. Salmonella typhimuriumB. Escherichia coliC. Bacillus thuringiensisD. Yeast

Minisatellites or VNTRs are used inA. DNA fingerprintingB. Polymerase Chain Reaction (PCR)C. gene therapyD. gene mapping

The role of DNA ligase in the construction of a recombinant DNA molecule is :A. formation of phosphodiester bond between two DNA fragementsB. formation of covalent bonds between sticky ends of DNA fragmentsC. Formation of H-bonds between all purine and pyrimidine basesD. None of the above

A recombinant DNA molecule can be produced in the absence of the followingt :A. E. coliB. DNA ligaseC. DNA fragmentsD. Restriction endonuclease

VNTRs are usually …. Long.A. 10-20,000 nucleotideB. 80-18000 nucleotideC. 10-100 nucleotideD. 1-10 nucleotide

A recombinant DNA molecule can be pro- duced in the absence of the following.A. Restriction endonucleaseB. DNA ligaseC. DNA fragmentsD. E. coli

Hybridomas are the fusion product of :A. normal antibody producing cell with myelomaB. abnormal antibody producing cell with myelomaC. sex cells with myelomaD. bone cells with myeloma

The vehicle DNA is aA. rDNAB. vectorC. gene of interestD. passenger DNA

Lyase enzymes are used toA. open the cellsB. join DNA fragmentsC. synthesise DNAD. cut DNA

RAPD can be expanded asA. restriction amplified polymorphic DNAB. Random amplified protein and DNAC. Random amplification of polymorphic DNAD. None of the above

Which technique made it possible to genetically engineer living organisms ?A. Heavier isotope labelingB. HybridisationC. Recombinant DNA techniquesD. X-ray diffraction

Genetically identifical copy of individual cell or gene is known asA. speciesB. phagmidC. cloneD. plasmid

Which is correct regarding genetically engineered insulin using E.coli ?A. Difficulty in purifying the productB. Obtained in large unlimited quantitiesC. Possibility of transmission of animal diseasesD. Insulin obtained varies in chemical structure

Plants having similar genotypes produced by plant breeding are calledA. clonesB. genomesC. haploidsD. autoploids

The first successful clone was named asA. NooriB. DollyC. PennyD. Jolly

The following steps are necessary to clone eukaryotic genes in bacteria . What is the third step ?A. TranscriptionB. Remove the intronsC. Splice exons togetherD. Reverse transcription of m-RMA

The first successful clone was developed byA. WilmutB. CampbellC. GlibertD. Both (a) and (b)

Genetically similar individuals of species are :A. chorotB. clonesC. colonyD. community

Clone Noori is aA. Pashmina goatB. calfC. sheepD. goat

Which of the following are used in gene cloning ?A. nucleoidsB. lomasomesC. mesosomesD. plasmids

The DNA molecule to which the gene of interst is integrated for cloning is calledA. vectorB. TemplateC. CarrierD. Transformer

178.	The role of DNA ligase in the construction of a recombinant DNA molecule is :A. Formation of phosphodiester bond between two DNA fragmentsB. Formation of hydrogen bonds between sticky ends of DNA fragmentsC. Ligation of all purine and pyrimidine basesD. All of the above
Answer» Correct Answer - A The role of DNA ligase in the construction of a recombinant DNA molecule is formation of phosphodiester bond between two DNA fragments

179.	The role of DNA ligase in the construction of a recmobinant DNA molecule isA. Formation of phosphodiester bond between two DNA fragmentsB. Formation of hydrogen bonds between sticky ends of DNA fragmentsC. Ligation of all purine and pyrimidine basesD. None of the these
Answer» Correct Answer - A

180.	Construction of first recombinant DNA was done by using plasmid ofA. Salmonella typhimuriumB. Escherichia coliC. Bacillus thuringiensisD. Yeast
Answer» Correct Answer - A Construction of first recombinant DNA was done by using plasmid of Salmonella typhimurium

181.	Minisatellites or VNTRs are used inA. DNA fingerprintingB. Polymerase Chain Reaction (PCR)C. gene therapyD. gene mapping
Answer» Correct Answer - a Minisatellities or Variable Number of Tandem Repeats (VNTRs) is used in DNA fingerprinting technique. In VNTR, satellite DNA as probe is used that shows very high degree of polymorphism. The technique used Southern blot hybridisation using radiolabelled VNTR as a probe.

182.	The role of DNA ligase in the construction of a recombinant DNA molecule is :A. formation of phosphodiester bond between two DNA fragementsB. formation of covalent bonds between sticky ends of DNA fragmentsC. Formation of H-bonds between all purine and pyrimidine basesD. None of the above
Answer» Correct Answer - a

183.	A recombinant DNA molecule can be produced in the absence of the followingt :A. E. coliB. DNA ligaseC. DNA fragmentsD. Restriction endonuclease
Answer» Correct Answer - A

184.	VNTRs are usually …. Long.A. 10-20,000 nucleotideB. 80-18000 nucleotideC. 10-100 nucleotideD. 1-10 nucleotide
Answer» Correct Answer - c

185.	A recombinant DNA molecule can be pro- duced in the absence of the following.A. Restriction endonucleaseB. DNA ligaseC. DNA fragmentsD. E. coli
Answer» Correct Answer - d

186.	Hybridomas are the fusion product of :A. normal antibody producing cell with myelomaB. abnormal antibody producing cell with myelomaC. sex cells with myelomaD. bone cells with myeloma
Answer» Correct Answer - A

187.	The vehicle DNA is aA. rDNAB. vectorC. gene of interestD. passenger DNA
Answer» Correct Answer - b