Biotechnology: Principles and Processes

Which one of the following statements is not true regarding gel electrophoresis technique?

1. The process of extraction of separated DNA strands from gel is called elution.
2. The separated DNA fragments are stained by using ethidium bromide.
3. The presence of chromogenic substrate gives blue coloured DNA bands on the gel.
4. Bright orange coloured bands of DNA can be observed in the gel when exposed to UV light.

In the following palindromic base sequences of DNA, which one can be cut easily by particular restriction enzyme?

1. 5'GATACT3' ; 3'CTATGA5'
2. 5'GAATTC3' ; 3'CTTAAG5'
3. 5'CTCAGT3' ; 3'GAGTCA5'
4. 5'GTATTC3' ; 3'CATAAG5'

Given below are two statements: In the light of the above statements, choose the most appropriate answer from the options given below :

1. Both Statement I and Statement II are correct
2. Both Statement I and Statement II are incorrect
3. Statement I is correct but Statement II is incorrect
4. Statement I is incorrect but Statement II is correct

Which of the following is not a desirable feature of a cloning vector?

1. Presence of origin of replication
2. Presence of a marker gene
3. Presence of single restriction enzyme site
4. Presence of two or more recognition sites

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). In the light of the above statements, choose the correct answer from the options given below :

1. (A) is not correct but (R) is correct
2. Both (A) and (R) are correct and (R) is the correct explanation of (A)
3. Both (A) and (R) are correct but (R) is not the correct explanation of (A)
4. (A) is correct but (R) is not correct

Separation of DNA fragments is done by a technique known as

1. Gel electrophoresis
2. Polymerase Chain Reaction
3. Recombinant technology
4. Southern blotting

The enzyme (a) is needed for isolating genetic material from plant cells and enzyme (b) for isolating genetic material from fungus. Choose the correct pair of options from the following :

1. (a) Cellulase (b) Lipase
2. (a) Cellulase (b) Protease
3. (a) Cellulase (b) Chitinase
4. (a) Chitinase (b) Lipase

Which of the following methods is not commonly used for introducing foreign DNA into the plant cell?

1. Bacteriophages
2. Agrobacterium mediated transformation
3. Gene gun
4. ‘Disarmed pathogen’ vectors

Refer to the following statements for agarose-gel electrophoresis: Choose the most appropriate answer from the options given below :

1. B, C and D only
2. A and B only
3. A, B and C only
4. A, B and D only

During the purification process for recombinant DNA technology, addition of chilled ethanol precipitates out :

1. Polysaccharides
2. RNA
3. DNA
4. Histones

DNA strands on a gel stained with ethidium bromide when viewed under UV radiation, appear as

1. Bright blue bands
2. Yellow bands
3. Bright orange bands
4. Dark red bands

Which of the following is a correct sequence of steps in a PCR (Polymerase Chain Reaction)?

1. Annealing, Denaturation, Extension
2. Denaturation, Annealing, Extension
3. Denaturation, Extension, Annealing
4. Extension, Denaturation, Annealing

Plasmid pBR322 has Pst I restriction enzyme site within gene ampR that confers ampicillin resistance. If this enzyme is used for inserting a gene for -galactosidase production and the recombinant plasmid is inserted in an E. coli strain

1. It will be able to produce a novel protein with dual ability
2. It will not be able to confer ampicillin resistance to the host cell
3. The transformed cells will have the ability to resist ampicillin as well as produce -galactosidase
4. It will lead to lysis of host cell

During the process of gene amplification using PCR, if very high temperature is not maintained in the beginning, then which of the following steps of PCR will be affected first?

1. Ligation
2. Annealing
3. Extension
4. Denaturation

A specific recognition sequence identified by endonucleases to make cuts at specific positions within the DNA is :

1. Poly (A) tail sequences
2. Degenerate primer sequence
3. Okazaki sequences
4. Palindromic Nucleotide sequences

In gel electrophoresis, separated DNA fragments can be visualized with the help of

1. Ethidium bromide in infrared radiation
2. Ethidium bromide in UV radiation
3. Acetocarmine in bright blue light
4. Acetocarmine in UV radiation

Identify the wrong statement with regard to Restriction Enzymes

1. Sticky ends can be joined by using DNA ligases.
2. They cut the strand of DNA at palindromic sites.
3. Each restriction enzyme functions by inspecting the length of a DNA sequence.
4. They are useful in genetic engineering

The specific palindromic sequence which is recognized by EcoRI is

1. 5′ - GGATCC - 3′ 3′ - CCTAGG - 5′
2. 5′ - GAATTC - 3′ 3′ - CTTAAG - 5′
3. 5′ - GGAACC - 3′ 3′ - CCTTGG - 5′
4. 5′ - CTTAAG - 3′ 3′ - GAATTC - 5′

The sequence that controls the copy number of the linked DNA in the vector, is termed

1. Recognition site
2. Ori site
3. Selectable marker
4. Palindromic sequence

Choose the correct pair from the following

1. Exonucleases – Make cuts at specific positions within DNA
2. Ligases – Join the two DNA molecules
3. Polymerases – Break the DNA into fragments
4. Nucleases – Separate the two strands of DNA

DNA precipitation out of a mixture of biomolecules can be achieved by treatment with :

1. Methanol at room temperature
2. Chilled chloroform
3. Isopropanol
4. Chilled ethanol

Following statements describe the characteristics of the enzyme Restriction Endonuclease. Identify the incorrect statement.

1. The enzyme cuts the sugar-phosphate backbone at specific sites on each strand
2. The enzyme recognizes a specific palindromic nucleotide sequence in the DNA
3. The enzyme cuts DNA molecule at identified position within the DNA
4. The enzyme binds DNA at specific sites and cuts only one of the two strands

Which one of the following equipments is essentially required for growing microbes on a large scale, for industrial production of enzymes?

1. Industrial oven
2. Bioreactor
3. BOD incubator
4. Sludge digester

The correct order of steps in Polymerase Chain Reaction (PCR) is

1. extension, denaturation, annealing
2. annealing, extension, denaturation
3. denaturation, extension, annealing
4. denaturation, annealing, extension

The DNA fragments separated on an agarose gel can be visualised after staining with

1. Bromophenol blue
2. Aniline blue
3. Ethidium bromide
4. Acetocarmine

DNA fragments are

1. Positively charged
2. Either positively or negatively charged depending on their size
3. Neutral
4. Negatively charged

A gene whose expression helps to identify transformed cell is known as

1. Selectable marker
2. Plasmid
3. Vector
4. Structural gene

What is the criterion for DNA fragments movement on agarose gel during gel electrophoresis ?

1. Positively charged fragments move to farther end
2. Negatively charged fragments do not move
3. The smaller the fragment size, the farther it moves
4. The larger the fragment size, the farther it moves

The process of separation and purification of expressed protein before marketing is called :

1. Upstream processing
2. Bioprocessing
3. Downstream processing
4. Postproduction processing

Which of the following is not a feature of the plasmids ?

1. Single-stranded
2. Transferable
3. Independent replication
4. Circular structure