Polymerase Chain Reaction MCQs : Here you will find MCQ Questions related to "Polymerase chain reaction" in Molecular Biology. These Polymerase chain reaction MCQ Questions Will help you to improve your Molecular Biology knowledge and will prepare you for various Examinations like Competitive Exams, Placements, Interviews and other Entrance Exmaniations.
Question 1
___________________ is a method widely used to rapidly make millions to billions of copies of a specific DNA sample, allowing scientists to take a very small sample of DNA and amplify it to a large enough amount to study in detail.
A. DEA
B. URS
C. PCR
D. ORA
View Answer
Ans : C
Explanation: Polymerase chain reaction (PCR) is a method widely used to rapidly make millions to billions of copies of a specific DNA sample, allowing scientists to take a very small sample of DNA and amplify it to a large enough amount to study in detail
Question 2
PCR was invented in?
A. 1980
B. 1981
C. 1982
D. 1983
View Answer
Ans : D
Explanation: PCR was invented in 1983 by the American biochemist Kary Mullis at Cetus Corporation.
Question 3
PCR amplifies a specific region of a _________ strand.
A. RNA
B. DNA
C. Both A and B
D. None of the above
View Answer
Ans : B
Explanation: PCR amplifies a specific region of a DNA strand (the DNA target). Most PCR methods amplify DNA fragments of between 0.1 and 10 kilo base pairs (kbp) in length, although some techniques allow for amplification of fragments up to 40 kbp
Question 4
PCR consists of a series of 20–40 repeated temperature changes, called thermal cycles.
A. TRUE
B. FALSE
C. Can be true or false
D. Can not say
View Answer
Ans : A
Explanation: True, PCR consists of a series of 20–40 repeated temperature changes, called thermal cycles, with each cycle commonly consisting of two or three discrete temperature steps.
Question 5
Which of the following is the final step that cools the reaction chamber to 4–15 °C (39–59 °F) for an indefinite time.
A. Extension
B. Final elongation
C. Final hold
D. elongation
View Answer
Ans : C
Explanation: Final hold: The final step cools the reaction chamber to 4–15 °C (39–59 °F) for an indefinite time, and may be employed for short-term storage of the PCR products.
Question 6
Initialization: This step is only required for DNA polymerases that require heat activation by hot-start PCR.
A. TRUE
B. FALSE
C. Can be true or false
D. Can not say
View Answer
Ans : A
Explanation: True, Initialization: This step is only required for DNA polymerases that require heat activation by hot-start PCR
Question 7
Which of the following is a mismatch?
A. Polymerase – Taq polymerase
B. Template – double stranded DNA
C. Primer – oligonucleotide
D. Synthesis – 5’ to 3’ direction
View Answer
Ans : B
Explanation: PCR uses the enzyme DNA polymerase that directs the synthesis of DNA from deoxynucleotide substrates on one stranded DNA template. DNA polymerase synthesizes DNA in a 5’→3’ direction and can add nucleotides in the 3’ end of a custom – designed oligonucleotide
Question 8
Primer used for the process of polymerase chain reaction are ______________
A. Single stranded DNA oligonucleotide
B. Double stranded DNA oligonucleotide
C. Single stranded RNA oligonucleotide
D. Double stranded RNA oligonucleotide
View Answer
Ans : A
Explanation: Two single stranded, oligonucleotide is synthesized and used as a primer. The primers thus produces binds to the denatured DNA and polymerase starts its synthesis in the 5’ to 3’ direction
Question 9
How many DNA duplex is obtained from one DNA duplex after 4 cycles of PCR?
A. 2
B. 4
C. 8
D. 16
View Answer
Ans : D
Explanation: After each cycle the number of duplexes doubles itself thus after the first cycle there are 2 DNA duplexes. A duplex has 2 DNA strands thus after second cycle there will be 4 Duplexes, after third cycle there will be 8 DNA duplex. Lastly, after the 4th cycle there will be 16 duplexes
Question 10
With respect to target DNA used in inverted PCR which of the following is not true?
A. Restricted segment
B. Blunt ended segment
C. Intact known segment
D. Flanked unknown segment flanked on either side
View Answer
Ans : B
Explanation: The target DNA is cut with a restriction enzyme that produces sticky ends and that does not cut within the region of which the sequence is known. The cutter instead cuts at unknown sites on the either sides of the known sequence. This lets the DNA circularize later, which is a very important step for achieving our desired results.