Genetic Engineering Multiple Choice Questions on “Applications of Genetic Engineering”.
1. Amplification of specific region can be done by using primers for specific regions. If the PCR product is ______ and is in sufficient quantity, then sequence can be determined ________
a) non-specific, directly
b) non-specific, indirectly or directly
c) specific, directly
d) specific, indirectly
Answer: c
Explanation: Amplification of specific region can be done by using primers for specific regions. If the PCR product is specific, it means that only a single band is obtained in gel electrophoresis and is insufficient quantity then the sequence can be determined directly.
2. Which of the following is not suitable if the PCR product is non-specific?
a) Adjusting the concentration of magnesium ions
b) Increasing annealing temperature
c) Using touchdown PCR
d) Using inverse PCR
Answer: d
Explanation: In case, products are non-specific then sequence can’t be known directly. Optimization of PCR should be carried out and various other strategies should be used such as adjusting the concentration of magnesium ions, increasing annealing temperature or using touch-down PCR.
3. The disadvantage in the approach based on using PCR is that there is no permanent record until some of the bacterial cells are preserved.
a) True
b) False
Answer: a
Explanation: The disadvantage of this approach is that there is no permanent record until some of the bacterial cells are preserved. If enough bacteria are there initially then genomic library can be constructed.
4. How many approaches are there in order to clone the complete genome?
a) 1
b) 2
c) 3
d) 4
Answer: b
Explanation: There are basically two approaches in order to clone the complete genome. In the first approach, systematic cloning is cloned is carried out. The second approach is based on cloning overlapping fragments at random.
5. If a full proteomic analysis of growth medium is carried out and is combined with ____________ genome sequence, genes for other _____________ proteins are also obtained.
a) partial, defensive
b) partial, secreted
c) complete, defensive
d) complete, secreted
Answer: d
Explanation: If a full proteomic analysis of growth medium is carried out and is combined with complete genome sequence, genes for other secreted proteins can also be obtained.
6. If a putative protein sequence is cloned in an expression vector and the expressed protein is not showing protease activity, then which of the following is not correct?
a) The protein is not protease
b) The protein can be incorrectly folded which can block the protease activity
c) There might be some other cofactor required for protease activity
d) The most commonly used expression system is E.coli
Answer: a
Explanation: If the putative protein sequence is cloned and the expressed protein is not showing protease activity, it is not necessary that it is not protease. Suppression of protease activity can be because of incorrect folding or that some cofactor is required for protease activity. The most commonly used expression system is E.coli.
7. For getting a large amount of proteins to crystallize, which of the following should be used as an expression system?
a) Bacterial system
b) Yeast systems
c) Eukaryotic systems
d) Both eukaryotic and bacterial systems can be used
Answer: d
Explanation: The system to be used for getting large amounts of proteins to crystallize can be either bacterial or eukaryotic. It depends on the source of the gene and whether post-translational modification is necessary or not.
8. If a mutation perturbs the structure, then stability and folding are not affected.
a) True
b) False
Answer: b
Explanation: At times mutated proteins are not expressed well. Mutation perturbs a structure at times and it affects the stability and folding of the protein.
9. The RNA level ___________ the steady-state level of the corresponding protein directly and the post-translational modification of the protein ____________
a) reflects, can be determined
b) reflects, can’t be determined
c) doesn’t necessarily reflects, can be determined
d) doesn’t necessarily reflects, can’t be determined
Answer: d
Explanation: The RNA level doesn’t necessarily correspond to the steady level of corresponding protein directly and the post-translational modification or location of the protein can’t be determined.
10. For a convenient transformation system, _____ can be used for gene silencing.
a) antisense RNA
b) transposon insertion
c) either antisense RNA or transposon insertion
d) transposon insertion followed by antisense RNA
Answer: a
Explanation: If a convenient transformation system is used, antisense RNA can be used for gene silencing. If the transformation system is not convenient then transposon insertion is used for silencing.