54658.Which of the following is not required in the preparation of recombinant DNA molecules?
Restriction endonucleases
DNA ligase
DNA fragments
E. coli
Explanation:
Restriction enzymes and DNA ligases can be used to make a stable recombinant DNA molecule with DNA fragments that has been spliced together from two differentorganisms
Restriction enzymes and DNA ligases can be used to make a stable recombinant DNA molecule with DNA fragments that has been spliced together from two differentorganisms
54659.In Agarose gel electrophoresis, DNA molecules are separated on the basis of their
Charge only
Size only
Charge to size ratio
All of these
Explanation:
In Agarose gel electrophoresis, the DNA fragments separate out (resolve) accordingto their size or length because of the sieving property of agarose gel means, the smaller the fragment size, the farther it will move.
In Agarose gel electrophoresis, the DNA fragments separate out (resolve) accordingto their size or length because of the sieving property of agarose gel means, the smaller the fragment size, the farther it will move.
54660.The most important feature-in a plasmid to be used as vector is
Origin of replication (ori)
Presence of a selectable marker
Presence of sites for restriction endonuclease
Its size
Explanation:
All of the given features are important to facilitate cloning into a vector but out of them Origin of replication (ori) is the most important one.This is due to the following reasons (i) Ori is a DNA sequence that is responsible for initiating replication. Any piece ofDNA when linked to this sequence can replicate within the host cells.(ii) Ori also controls the copy numbers of the linked DNA.
All of the given features are important to facilitate cloning into a vector but out of them Origin of replication (ori) is the most important one.This is due to the following reasons (i) Ori is a DNA sequence that is responsible for initiating replication. Any piece ofDNA when linked to this sequence can replicate within the host cells.(ii) Ori also controls the copy numbers of the linked DNA.
54661.While isolating DNA from bacteria, which of the following enzymes is not used?
Lysozyme
Ribonuclease
Deoxyribonuclease
Protease
Explanation:
In the process of 'recombinant DNA technology' the first steps Isolation of DNA.Since, the DNA is enclosed within the membranes;we have to break the cell open to release DNA along with other macromolecules such as RNA proteins, polysaccharides and also lipids.This can be achieved by treating the bacterial cells/plant toanimal tissue with enzymessuch as lysozyme (bacteria), cellulase (plant cells) andchitinase (fungus).
In the process of 'recombinant DNA technology' the first steps Isolation of DNA.Since, the DNA is enclosed within the membranes;we have to break the cell open to release DNA along with other macromolecules such as RNA proteins, polysaccharides and also lipids.This can be achieved by treating the bacterial cells/plant toanimal tissue with enzymessuch as lysozyme (bacteria), cellulase (plant cells) andchitinase (fungus).
54662.Which of the following has popularised the PCR (Polymerase Chain Reaction)?
Easy availability of DNA template
Availability of synthetic primers
Availability of cheap deoxyribonucleotides
Availability of 'Thermos table' DNA polymerase
Explanation:
The Polymerase Chain Reaction (PCR) is a reaction in which amplification of specific DNA sequences is carried out in vitro. Such repeated amplification is achieved by the use of a thermostable DNA polymerase (isolated from a bacterium, Thermus aquaticus), which remain active and stable during the high temperature and induced denaturation of double-standard DNA.
The Polymerase Chain Reaction (PCR) is a reaction in which amplification of specific DNA sequences is carried out in vitro. Such repeated amplification is achieved by the use of a thermostable DNA polymerase (isolated from a bacterium, Thermus aquaticus), which remain active and stable during the high temperature and induced denaturation of double-standard DNA.
54663.An antibiotic resistance gene in a vector usually helps in the selection of
Competent cells
Transformed cells
Recombinant cells
None of these
Explanation:
Selectable markers help in identifying and eliminating non-transformantsand selectively permitting the growth of the transformants. The normal E. coli cells do not carry resistance against any of these antibiotics. Competentbacterial cells are made capable to take foreign DNA with chemical treatment, e.g., calcium chloride.NoteIn process of transformation, a piece of DNA is introduced in a host bacterium.
Selectable markers help in identifying and eliminating non-transformantsand selectively permitting the growth of the transformants. The normal E. coli cells do not carry resistance against any of these antibiotics. Competentbacterial cells are made capable to take foreign DNA with chemical treatment, e.g., calcium chloride.NoteIn process of transformation, a piece of DNA is introduced in a host bacterium.
54664.Significance of heat shock method in bacterial transformation is to facilitate.
Binding of DNA to the cell wall
Uptake of DNA through membrane transport proteins
Uptake of DNA through transient pores in the bacterial cell wall
Expression of antibiotic resistance gene
Explanation:
In chemical method, the cell is treated with specific concentration of a divalent cation such as calcium to increase pore size in cell wall. The cells are incubated with recombinant DNA on ice, followed by placing them briefly at 42 degree Celcius and then putting it back on ice. This is called heat shock method. The bacteria now takes up the recombinant DNA.
In chemical method, the cell is treated with specific concentration of a divalent cation such as calcium to increase pore size in cell wall. The cells are incubated with recombinant DNA on ice, followed by placing them briefly at 42 degree Celcius and then putting it back on ice. This is called heat shock method. The bacteria now takes up the recombinant DNA.
54665.The role of DNA Ligasein the construction of a recombinant DNA molecule is
formation of phosphodiester bond between two DNA fragments
formation of hydrogen bonds between sticky ends of DNA fragments
ligation of all purine and pyrimidine bases
None of the above
Explanation:
DNA ligase (joining or sealing enzymes) are also called genetic gum. They join two individual fragments of double-stranded DNA by forming phosphodiester bonds between them. Thus they help in sealing gaps in DNA fragments. Therefore, they act as molecularglue.
DNA ligase (joining or sealing enzymes) are also called genetic gum. They join two individual fragments of double-stranded DNA by forming phosphodiester bonds between them. Thus they help in sealing gaps in DNA fragments. Therefore, they act as molecularglue.
54666.Which of the following is not a source of restriction endonuclease?
Haemophilus influenzae
Escherichia coli
Agrobacterium tumefaciens
Bacilius amyloli
Explanation:
Agrobacterium tumefaciens is a pathogen of several dicotplants. It delivers a piece of DNA known as 'T-DNA' in the Tiplasmid which transforms normal plant cells into tumour cells to produce chemicals against pathogens.The restriction enzyme Eco Rl, is isolated from Escherichia coli RY13.The first restriction enzymes Hind II was isolated from bacterium Haemophilus influenzae. The restriction enzyme Bam HI is isolated from Bacillus amyloli.
Agrobacterium tumefaciens is a pathogen of several dicotplants. It delivers a piece of DNA known as 'T-DNA' in the Tiplasmid which transforms normal plant cells into tumour cells to produce chemicals against pathogens.The restriction enzyme Eco Rl, is isolated from Escherichia coli RY13.The first restriction enzymes Hind II was isolated from bacterium Haemophilus influenzae. The restriction enzyme Bam HI is isolated from Bacillus amyloli.
54667.Which of the following steps are catalysed by Taq polymerase in a PCR reaction?
Denaturation of templateDNA
Annealing of primers to template DNA
Extension of primer end on the template DNA
All of the above
Explanation:
In polymerase chain reaction polymerisation or extension step is catalysed by Taqpolymerase enzyme. PCR is carried out in the following three steps.Extension DNA polymerase extends the primers by addingnucleotidescomplementary to the template provided in the reaction.A thermostable DNA polymerase (Taq DNA polymerase) is used in the reaction whichcan tolerate the high temperature of the reaction.
In polymerase chain reaction polymerisation or extension step is catalysed by Taqpolymerase enzyme. PCR is carried out in the following three steps.Extension DNA polymerase extends the primers by addingnucleotidescomplementary to the template provided in the reaction.A thermostable DNA polymerase (Taq DNA polymerase) is used in the reaction whichcan tolerate the high temperature of the reaction.
54668.A bacterial cell was transformed with a recombinant DNA that was generated using a human gene. However, the transformed cells did not produce the desired protein. Reasons could be
human gene may have intron which bacteria cannot process
aminoacid codons for humans and bacteria are different
human protein is formed but degraded by bacteria
All of the above
Explanation:
The process of making recombinant DNA molecule involves the introduction of a desired gene into the DNA of a host that will produce the desired protein. Inducing a cloned eukaryotic gene to function in a prokaryotic host can be difficult sometime. The presence of long non-coding introns in eukaryotic genes may prevent correct expression of these genes in prokaryotes, which lack RNA-splicing machinery.
The process of making recombinant DNA molecule involves the introduction of a desired gene into the DNA of a host that will produce the desired protein. Inducing a cloned eukaryotic gene to function in a prokaryotic host can be difficult sometime. The presence of long non-coding introns in eukaryotic genes may prevent correct expression of these genes in prokaryotes, which lack RNA-splicing machinery.
54669.Which of the following should be choosen for best yield if one were to produce a recombinant protein in large amounts?
Laboratory flask of largest capacity
A stirred-tank bioreactor without in-lets and out-lets
A continuous culture system
Any of the above
Explanation:
If any protein encoding gene is expressed in a heterologous host, it is called a recombinant protein. The cells has bring the cloned genes of interest may be grown on a small scale in the laboratory.The cultures may be used for extracting the desired protein and then purifying it by using different separation techniques.The cells can also be multiplied in a continuous culture system where in the used medium is drained out from one side while fresh medium is added from the other to maintain the cells in their physiologically most active log/exponential phase. This type of culturing method produces a larger biomass leading to higher yields of desired protein.
If any protein encoding gene is expressed in a heterologous host, it is called a recombinant protein. The cells has bring the cloned genes of interest may be grown on a small scale in the laboratory.The cultures may be used for extracting the desired protein and then purifying it by using different separation techniques.The cells can also be multiplied in a continuous culture system where in the used medium is drained out from one side while fresh medium is added from the other to maintain the cells in their physiologically most active log/exponential phase. This type of culturing method produces a larger biomass leading to higher yields of desired protein.
54670.Who among the following was awarded the Nobel Prize for the development of PCR technique?
Herbert Boyer
Hargovind Khurana
Kary Mullis
Arthur Kornberg
Explanation:
PCR (Polymerase Chain Reaction) technique was developed by Kary Mullis in 1985, and for this he received Nobel Prize for chemistry in 1993. HG Khurana discovered DNA ligase enzyme in to phage in 1969.
PCR (Polymerase Chain Reaction) technique was developed by Kary Mullis in 1985, and for this he received Nobel Prize for chemistry in 1993. HG Khurana discovered DNA ligase enzyme in to phage in 1969.
54671.Which of the following statements does not hold true for restriction enzyme?
It recognises a palindromic nucleotide sequence
It is an endonuclease
It is isolated from viruses
It produces the same kind of sticky ends in different DNA molecules
Explanation:
The restriction enzymes are called 'molecular scissors' and are responsible for cutting DNA on specific sites. These are not found in viruses.
The restriction enzymes are called 'molecular scissors' and are responsible for cutting DNA on specific sites. These are not found in viruses.
54672.The importance of gas bubbles in sparged tank reactor is that
Gas bubbles are meant for sterilisation of the culture
Bubbles dramatically increase the oxygen transfer area
Bubbles help in purification of culture
Bubbles help in easy release of product from sampling port
Explanation:
Bubbles carry oxygen in them and hence they dramatically increase the oxygen transfer area
Bubbles carry oxygen in them and hence they dramatically increase the oxygen transfer area
54673.In transgenics expression of transgene in target tissue is determined by
Enhancer
Transgene
Promoter
Reporter
Explanation:
A reporter is a gene that researchers attract to a regulatory sequence of another gene of interest in the target tissue and it is for identifying those few successful gene uptake events.
A reporter is a gene that researchers attract to a regulatory sequence of another gene of interest in the target tissue and it is for identifying those few successful gene uptake events.
54674.A kind of biotechnology involving in manipulation of DNA is
DNA replication
Genetic Engineering
Denaturation
Renaturation
Explanation:
The genetic engineering rDNA technology is applied to several biotechnological processes for obtaining particular biochemical improvement of genetic makeup of an organism and fighting genetic defects.
The genetic engineering rDNA technology is applied to several biotechnological processes for obtaining particular biochemical improvement of genetic makeup of an organism and fighting genetic defects.
54675.The TI plasmid used in genetic engineering is obtained from
Bacilus thuringeinsis
Agrobacterium rhizogenes
Agrobacterium tumifaciens
E.coli
Explanation:
The Ti plasmid is present in Agrobacterium tumifaciens .Agrobacterium is naturally occuring gram negative,soil bacteria with two common species, like A.tumifaciens and A.rhizogenes.
The Ti plasmid is present in Agrobacterium tumifaciens .Agrobacterium is naturally occuring gram negative,soil bacteria with two common species, like A.tumifaciens and A.rhizogenes.
54676.In which of the following technique the bacterium Thermus Aquatics is used?
ELISA
PCR
Biolistic
Autoradiography
Explanation:
Thermus aquaticus has proven to be quite organism in the field of biotechnology ,as its enzyme Taq polymarase is harvested for use in PCR.
Thermus aquaticus has proven to be quite organism in the field of biotechnology ,as its enzyme Taq polymarase is harvested for use in PCR.
54677.garose extracted from sea weeds finds use in
Spectrophotometery
Tissue culture
PCR
Gel Electrophoresis
Explanation:
In gel electrophoresis agarose extracted from sea weeds used as gel agarose made up of 0.7% gel show good resolution of large DNA and 2% gel will shows resolution of small fragments.
In gel electrophoresis agarose extracted from sea weeds used as gel agarose made up of 0.7% gel show good resolution of large DNA and 2% gel will shows resolution of small fragments.