Biology MCQ

#11 Biology Class XII- Biotechnology: Principles and Processes (NEET, MHTCET) MCQ


 MCQ

1) Restriction endonuclease   
(a) synthesizes DNA 
(b) cuts the DNA molecues randomly 
(c) cuts the DNA molecule at specific sites 
(d) restricts the synethesis of DNA inside the nuclease
Answer 
(c) cuts the DNA molecule at specific sites

 
 
2) The linking of antibiotic resistance gene with the plasmid vector became possible with

(a) DNA polymerase    
(b) exonucleases 
(c) DNA ligase    
(d) endonucleases
Answer 
(c) DNA ligase   

 
 
3) Stirred-tank bioreactors have been designed for

(a) addition of preservatives to the product 
(b) purification of the product 
(c) ensuring anaerobic conditions in the culture vessel 
(d) availability of oxygen throughout the process
Answer 
 (d) availability of oxygen throughout the process

 
 
4) Given below is a sample of a portion of DNA strand giving the base sequence on the opposite strands. What is so special shown in it?

5′_____GAATTC_____3′

3′_____CTTAAG_____5′

(a) Replication completed    
(b) Deletion mutation 
(c) Start codon at the 5′ level  
(d) Palindromic sequence of base pairs
Answer 
(d) Palindromic sequence of base pairs

 
 
5) There is a restriction endonuclease called Eco RI. What does “co” part in it stand for?

(a) Colon    
(b) Coelom 
(c) Coenzyme    
(d) Coli
Answer 
(d) Coli

 
 
6) Agarose extracted from sea weeds is used in

(a) spectrophotometry    
(b) tissue culture 
(c) PCR   
 (d) gel electrophoresis
Answer 
 (d) gel electrophoresis

 
 
7) An enzyme catalysing the removal of nucleotides from the ends of DNA is [NCERT Exemplar]

(a) endonuclease 
(b) exonuclease 
(c) DNA ligase 
(d) Hind-II
Answer 
(b) exonuclease

 
 
8) The transfer of genetic material from one bacterium to another through the mediation of a viral vector is termed as: [NCERT Exemplar]

(a) transduction 
(b) conjugation 
(c) transformation 
(d) translation
Answer 
(a) transduction

 
 
9) Which of the given statements is correct in the context of observing DNA separated by agarose gel electrophoresis? [NCERT Exemplar]

(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
Answer 
(d) Ethidium bromide stained DNA can be seen under exposure to UV light

 
 
10) Which of the following is not a characterstic of the plasmids ?

(a) Extranuclear 
(b) Single-stranded 
(c) Independent replication 
(d) Circular DNA
Answer 
(b) Single-stranded

 
 
11) DNA fragments generated by the restriction endonuclease in a chemical reaction can be separated by

(a) Gel electrophoresis 
(b) Restriction mapping 
(c) Centrifugation 
(d) PCR
Answer 
(a) Gel electrophoresis

 
 
12) Which of the following is not required in the preparation of a recombinant DNA molecule? [NCERT Exemplar]

(a) Restriction endonuclease 
(b) DNA ligase 
(c) DNA fragments 
(d) E.coli
Answer 
(d) E.coli

 
 
13) In agarose gel electrophoresis, DNA molecules are separated on the basis of their [NCERT Exemplar]

(a) charge only 
(b) size only 
(c) charge to size ratio 
(d) All of the above
Answer 
(d) All of the above

 
 
14) The most important feature in a plasmid to be used as a vector is [NCERT Exemplar]

(a) origin of replication (ori) 
(b) presence of a selectable marker 
(c) presence of sites for restriction endonuclease 
(d) its size
Answer 
(a) origin of replication (ori)

 
 
15) While isolating DNA from bacteria, which of the following enzymes is not required? [NCERT Exemplar]

(a) Lysozyme 
(b) Ribonuclease 
(c) Deoxyribonuclease 
(d) Protease
Answer 
(c) Deoxyribonuclease

 
 
16) Which of the following has popularised the PCR (polymerase chain reactions)? [NCERT Exemplar]

(a) Easy availability of DNA template 
(b) Availability of synthetic primers 
(c) Availability of cheap deoxyribonucleotides 
(d) Availability of ‘Thermostable’ DNA polymerase
Answer 
(d) Availability of ‘Thermostable’ DNA polymerase

 
 
17) Select the correct sequence of processing of PCR.

(a) Extension, primer annealing, denaturation 
(b) Denaturation, primer annealing, extension 
(c) Denaturation, extension, primer annealing 
(d) Primer annealing, denatturatiotn, extension
Answer 
(b) Denaturation, primer annealing, extension

 
 
18) Which of the following is/are used in recombinant DNA technology ?

1. Agarose gel
2. Restriction endonuclease
3. Plasmid vector
4. Ethidium bromide

(a) 1 and 2 
(b) 2 and 3 
(c) 3 and 4 
(d) All of these
Answer 
(d) All of these

 
 
19) An antibiotic resistance gene in a vector usually helps in the selection of [NCERT Exemplar]

(a) competent cells 
(b) transformed cells 
(c) recombinant cells 
(d) none of the above
Answer 
(b) transformed cells

 
 
20) Significance of ‘heat shock’ method in bacterial transformation is to facilitate [NCERT Exemplar]

(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
Answer 
(c) uptake of DNA through transient pores in the bacterial cell wall

 
 
21) The role of DNA ligase in the construction of a recombinant DNA molecule is [NCERT Exemplar]

(a) formation of phosphodiester bond between two DNA fragments 
(b) formation of hydrogen bonds between sticky ends of DNA fragments 
(c) ligation of all purime and pyrimidine bases 
(d) None of the above
Answer 
(a) formation of phosphodiester bond between two DNA fragments

 
 
22) Which of the following steps are catalysed by Taq DNA polymerase in a PCR reaction? [NCERT Exemplar]

(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
Answer 
(c) Extension of primer end on the template DNA

 
 
23) A bacterial cell was transformed with a recombinant DNA molecule that was generated using a human gene. However, the transformed cells did not produce the desired protein. Reasons could be:[NCERT Exemplar]

(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
Answer 
(a) Human gene may have intron which bacteria cannot process

 
 
24) In genetic engineering, the antibiotics are used 

(a) as selectable markers 
(b) to keep the cultures free of inection 
(c) to select healthy vectors 
(d) as sequence from where replication starts
Answer 
(a) as selectable markers

 
 
25) Which of these is not correctly matched? 

(a) Gene gun—biolistic gun 
(b) Plasmids—extrachromosomal DNA 
(c) DNA ligase—biological scissors 
(d) Bacteriophages—viruses
Answer 
(c) DNA ligase—biological scissors

 
 
26) Which of the following statements does not hold true for restriction enzyme? [NCERT Exemplar]

(a) It recognises a palindromic nucleotide sequence 
(b) It is an endonuclease 
(c) It is isolated from viruses 
(d) It can produce the same kind of sticky ends in different DNA molecules
Answer 
(c) It is isolated from viruses