An important limitation to the use of Agrobacterium tumefaciens is that it can not:
1. infect dicots
2. be genetically modified
3. be cultured on a nutrient medium
4. infect crop plants such as wheat and corn
Identify a character that is not desirable in a cloning vector:
1. an inactive promoter
2. an origin of replication site
3. selectable markers such as genes for antibiotic resistance
4. one or more unique restriction endonuclease sites
A cloning vector has two antibiotic resistance genes- for tetracycline and ampicillin. A foreign DNA
was inserted into the tetracycline gene. Non-recombinants would survive on the medium containing :
1. ampicillin but not tetracycline
2. tetracycline but not ampicillin
3. both tetracycline and ampicillin
4. neither tetracycline nor ampicillin
A host cell normally does not take up a foreign DNA until it has been made competent to do so. This is because:
1. DNA is a hydrophilic molecule
2. DNA is a very large molecule
3. there are no receptors for DNA on the cell membrane
4. DNA is an inert molecule
The first type II restriction endonuclease discovered that could cut dsDNA specific site was:
3. Hind II
4. Hind III
The technique not used for transformation of plant cells in recombinant procedures is:
2. Agrobacterium mediation
3. Use of viruses
In the screening process during rDNA experiments, clones that metabolize β-gal turn:
The plasmid pBR322 does not contain:
1. An origin of replication site
2. A gene that encodes for restrictor of plasmid copy number
3. Gene for Ampicillin and Streptomycin resistance
4. Sites for many restriction enzymes
The process of separation and purification of expressed protein before marketing is called
(1) upstream processing
(2) downstream processing
(4) postproduction processing
Credit for construction of first recombinant DNA may be given to
(1) Charles Darwin and Alfred Wallace
(2) Stanley Cohen and Herbert Boyer
(3) Meselson and Stahi
(4) Esther and Joshua Lederberg
Which of the following represents a correct palindromic sequence recognised by EcoRl?
Restriction in Restriction endonuclease enzyme refers to
(1) cleaving of phosphodiester bond in DNA by the enzyme
(2) Cutting of DNA at specific position only
(3) Prevention of bacteriophage multiplication in bacteria
(4) Cutting each of the two strands of DNA at specific points in sugar phosphate backbone
Which of the following steps is/are catalysed by Taq polymerase in a PCR?
(1) Denaturation of template DNA
(2) Annealing of primers to template DNA
(3) Extension of primer end on template DNA
(4) All of these
In case of Bam HI, H represents
(3) Name of scientist
Normal E. coil cells carry resistance against which of the following antibiotics?
(4) None of these
Which of the following statements is correct in the context of observing DNA separated by agarose gel electrophoresis?
(1) DNA can be seen in visible light
(2) DNA can be seen without staining in visible light
(3) Ethidium bromide stained DNA can be seen in visible light
(4) Ethidium bromide stained DNA can be seen under exposure to UV light
In agarose gel electrophoresis, DNA molecules of different lengths are separated on the basis of their
(1) Charge only
(2) Size only
(3) Charge to size ratio
(4) Both (1) & (3)
Significance of treating bacterial cells with calcium chloride before transformation is to facilitate
(1) Binding of DNA to the cell surface
(2) Uptake of DNA through membrane transport proteins
(3) Uptake of DNA by creating transient pores in the bacterial cell wall
(4) Expression of antibiotic resistance gene
Pure DNA precipitated by addition of chilled ethanol can be removed from solution by
(2) Gel electrophoresis
The optimum temperature for polymerisation in PCR is _____________ while the enzyme responsible for the mentioned step can tolerate temperatures upto __________. Select the correct option according to the blanks.
(1) 95C, 60C
(2) 94C, 95C
(3) 72C, 95C
(4) 95C, 72C
Stirrer in stirred tank type bioreactor facilitates
(1) Oxygen delively from outside to inside
(2) Mixing and aeration
(3) Temperature control
(4) Foam control
Separation and purification by filtration, centrifugation of desired compound produced in bioreactor is a part of
(1) Downstream processing only
(2) Scaling up and downstream processing
(3) Upstream processing
(4) Screening for recombinants and downstream processing
Each restriction endonuclease functions by inspecting the length of DNA sequence. It cleaves _______________.
(1) Only the master strand to produce sticky end
(2) Sense strand of DNA to produce sticky ends
(3) Each of the two strands of the double helix at specific points in their sugar phosphate backbones
(4) Messenger RNA to remove exons
A set of bacterial clones, each containing a plasmid or phage, is called
(1) Gene library
(2) Gene pool
Select the option that excludes characteristics applicable to plasmids
(a) Circular DNA
(b) Linear DNA
(c) Present in all bacteria
(d) Contain essential genes
(e) Extra chromosomal self-replicating
(1) b & d only
(2) b, c & d only
(3) d b, e & c only
(4) a only
PCR is used for
(1) Reversing transcribing RNA into DNA
(2) Digesting DNA
(3) Amplifying DNA
(4) Amplifying proteins and separating DNA
The correct order of steps in Polymerase Chain Reation (PCR) is
(1) Extension Denaturation, Annealing
(2) Annealing, Extension, Denaturation
(3) Denaturation, Annealing, Extension
(4) Denaturation, Extension, Annealing
A gene whose expression helps to identify transformed cell is known as
(1) Selectable marker
(4) Structural gene
What is the criterion for DNA fragments movement on agarose gel during gel electrophoresis?
(1) The larger the fragment size, the farther it moves
(2) The smaller the fragment size, the farther it moves
(3) Positively charged fragments move to farther end
(4) Negatively charged fragments do not move
A foreign DNA and plasmid cut by the same restriction endonuclease can be joined to form a recombinant plasmid using
(1) Eco RI
(2) Taq polymerase
(3) Polymerase III
Which of the following is not a component of downstream processing?
Which of the following restriction enzymes produces blunt ends?
(1) sal I
(2) Eco RV
(3) Xho I
(4) Hind III
Which vector can clone only a small fragment of DNA?
(1) Bacterial artificial chromosome
(2) Yeast artificial chromosome
Which of the following is not correctly matched for the oranism and its cell wall degrading enzyme?
(1) Plant cells - Cellulase
(2) Algae - Methylase
(3) Fungi - Chitinase
(4) Bacteria - Lysozyme
The colonies of recombinant bacteria appear white in contrast to colonies of non-recombinant bacteria because of
(1) Insertional inactivation of alpha-galactosidase in non-recombinant bacteria
(2) Insertional inactivation of beta-galactosidase in recombinant bacteria
(3) Inactivation of glycosidase enzyme in recombinant bacteria
(4) Non-recombinant bacteria containing beta-galactosidase
The figure below is the diagrammatic representation of the E.coli vector pBR 322. Which one of the given options correctly identifies its certain component(s)?
(1) - antibiotic resistance genes
(2) ori-original restriction enzyme
(3) rop-reduced osmotic pressure
(4) Hind III, EcoRI - selectable markers
The figure below shows three steps (A, B, C) of Polymerase Chain Reaction (PCR). Select the option giving correct identification together with what it represents?
(1) A - Annealing with two sets of primers
(2) B - Denaturation at a temperature of about separating the two DNA strands
(3) A - Denaturation at a temperature of about C
(4) C - Extension in the presence of heat stable DNA polymerase
Continuous addition of sugars in 'fed batch' fermentation is done to
(1) Degrade sewage
(2) Produce methane
(3) Obtain antibiotics
(4) Purify enzymes
Production of a human protein in bacteria by genetic engineering is possible because
(1) Bacterial cell can carry out the RNA splicing reactions
(2) The human chromosome can replicate in bacterial cell
(3) The mechanism of gene regulation is identical in humans and bacteria
(4) The genetic code is universal
Which one of the following hydrolyses internal phosphodiester bonds in a polynucleotide chain?
All the following statements about stanley Cohen and Herbert Boyer are correct but one is wrong. Which one is wrong?
(1) They discovered recombinant DNA (r-DNA) technology which marked the birth of modern biotechnology.
(2) They first produced, healthy sheep clone, a Finn Dorset lamb, Dolly, form the differentiated adult mammary cells.
(3) They invented genetic engineering by combining a piece of foreign DNA containing a gene from a bacterium with a bacterial (E.coli) plasmid using the enzyme restriction endonuclease.
(4) They isolated the antibiotic resistance gene by cutting out a piece of DNA from a plasmid which was responsible for conferring antibiotic resistance.
Extraction of bands of DNA from the agarose gel is temed as
(1) Down stream processing
(2) Upstream processing
(4) Insertional inactivation
In plant biotechnology, PEG is used in
(1) Protoplast isolation
(2) Cell culture preparation
(3) Protoplast fusion
Restriction enzymes cut the strand of DNA a little away from the centre of the palindromic site, but between the same two bases on the opposite single stranded strands, these overhanging stretches formed on each strand are called __________.
(1) Blunt ends
(2) Sticky ends
(3) Staggered end
(4) Both (2) & (3)
Which of the following is considered as molecular glue?
(1) Alkaline phosphatase
(2) Restriction endonuclease
(3) DNA ligase
(4) DNA polymerase
What would happen if a recombinant DNA is inserted within the coding sequence of an enzyme, galactosidase?
(1) This will result in the inactivation of the enzyme
(2) The presence of chromogenic substrate will give blue coloured colonies
(3) The recombinant colonies do not produce any colour
(4) Both (1) & (3) are correct
You suspect your patient to be suffering from a bacterial disease, however the number of bacteria in the patient's body is very less. which method can help you detect these pathogens in the laboratory?
(1) Hybridoma technology
(3) Somatic hybridization
(4) DNA fingerprinting
(1) Formed by reverse transcriptase
(2) Cloned DNA
(3) Circular DNA
(4) Recombinant DNA
A: Restriction enzymes belong to a larger class of enzymes called nucleases.
R: Each restriction enzyme recognises a specific palindromic nucleotide sequence in the DNA.
A: Taq Polymerase is involved in PCR technique.
R: This enzyme remain active during the high temperature including denaturation of double stranded DNA.
A: Pst I generates single stranded over hanging stretches in DNA after digestion that facilitate ligation.
R: These short extensions can form phosphodiester bonds with their complementary counterparts.