MCQs of RDT Ch-1, Class 12

An enzyme catalysing the removal of nucleotides from the ends of
DNA is:
a. endonuclease
b. exonuclease
c. DNA ligase
d. Hind – II

The transfer of genetic material from one bacterium to another through
the mediation of a vector like virus is termed as:
a. Transduction
b. Conjugation
c. Transformation
d. Translation

Which of the given statement is correct in the context of observing DNA
separated by agarose gel electrophoresis?
a. DNA can be seen in visible light
b. DNA can be seen without staining in visible light
c. Ethidium bromide stained DNA can be seen in visible light
d. Ethidium bromide stained DNA can be seen under exposure to
UV light

An antibiotic resistance gene in a vector usually helps in the selection of:
a. Competent cells
b. Transformed cells
c. Recombinant cells
d. None of the above

Significance of ‘heat shock’ method in bacterial transformation is to
facilitate:
a. Binding of DNA to the cell wall
b. Uptake of DNA through membrane transport proteins
c. Uptake of DNA through transient pores in the bacterial cell wall
d. Expression of antibiotic resistance gene

The role of DNA ligase in the construction of a recombinant DNA
molecule is:
a. Formation of phosphodiester bond between two DNA fragments
b. Formation of hydrogen bonds between sticky ends of DNA
fragments
c. Ligation of all purine and pyrimidine bases
d. None of the above

Which of the following bacteria is not a source of restriction
endonuclease?
a. Haemophilus influenzae
b. Escherichia coli
c. Agrobacterium tumefaciens
d. Bacillius amyloli

Which of the following steps are catalysed by Taq polymerase in a PCR
reaction?
a. Denaturation of template DNA
b. Annealing of primers to template DNA
c. Extension of primer end on the template DNA
d. All of the above

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:
a. Human gene may have intron which bacteria cannot process
b. Amino acid codons for humans and bacteria are different
c. Human protein is formed but degraded by bacteria
d. All of the above

Who among the following was awarded the Nobel Prize for the
development of PCR technique?
a. Herbert Boyer
b. Hargovind Khurana
c. Kary Mullis
d. Arthur Kornberg

Which of the following statements does not hold true for restriction
enzyme?
a. It recognises a palindromic nucleotide sequence
b. It is an endonuclease
c. It is isolated from viruses
d. It produces the same kind of sticky ends in different DNA
molecules

A recombinant DNA molecule can be produced in the absence of the
following:
a. Restriction endonuclease
b. DNA ligase
c. DNA fragments
d. E.coli

In agarose gel electrophoresis, DNA molecules are separated on the basis
of their:
a. Charge only
b. Size only
c. Charge to size ratio
d. All of the above

The most important feature in a plasmid to be used as a vector is:
a. Origin of replication (ori)
b. Presence of a selectable marker
c. Presence of sites for restriction endonuclease
d. Its size

While isolating DNA from bacteria, which of the following enzymes is not
used?
a. Lysozyme
b. Ribonuclease
c. Deoxyribonuclease
d. Protease

Which of the following has popularised the PCR (polymerase chain
reactions)?
a. Easy availability of DNA template
b. Availability of synthetic primers
c. Availability of cheap deoxyribonucleotides
d. Availability of ‘Thermostable’ DNA polymerase