PCR Cycle

Q.

Who among the following was awarded the Nobel Prize for the development of PCR technique?

1. Kary Mullis

2. Herbert Boyer

3. Arthur Kornberg

4. Har Gobind Khurana

Q. The figure below shows three steps (A, B, C) of polymerase chain reaction (PCR). Select the option giving correct identification together with what it represents?

1. $\text{B-Denaturation at a temperature of about}$ ${50}^{\circ }C$
2. $\text{C-Denaturation at a temperature of about}{98}^{\circ }C\text{separating the two DNA strands}$
3. $\text{C-Extension in the presence of heat stable DNA polymerase}$
4. $\text{A-Annealing with two sets of primers}$

Q. Synthesis of leading and lagging strand require a

1. single primer
2. many and single primers respectively
3. many primers
4. single and many primers respectively

Q. Palaeontologists unearthed a human skull during excavation. A small fragment of scalp tissue was still attached to it. Only little DNA could be extracted from it. If the genes of the ancient man need to be analysed, the best way of getting sufficient amount of DNA from this extract is:

1. By subjecting the DNA into polymerase chain reaction
2. By subjecting the DNA into gel electrophoresis
3. By treating the DNA with restriction endonucleases
4. By hybridizing the DNA with the DNA probe

Q. The thermostable enzymes, ‘Taq’ and ‘Pfu’, isolated from thermophilic bacteria are

1. RNA polymerases
2. DNA polymerases
3. restriction endonucleases
4. DNA ligases

Q. How many sticky ends will be produced if a plasmid vector is digested at a single site by EcoR I?

1. 1
2. 2
3. 4
4. 6

Q. Which of the following steps is catalysed by Taq DNA polymerase in PCR reaction?

1. Denaturation of template DNA
2. Annealing of primers to template DNA
3. Extension of primer
4. Rejoining of template DNA.

Q. If the “annealing” step is missed during PCR, what would be its effect on the entire process?

1. DNA strands will not separate.
2. Primers will not attach.
3. DNA Polymerase would not work.
4. DNA will not extend.

Q. DNA polymerase can be obtained from

1. pBR 322
2. Thermus aquaticus
3. Agrobacterium
4. Retro virus

Q. Annealing process in the PCR needs a temperature of ${72}^{\circ }C.$

1. True
2. False

Q. Which of the following scientists won the Nobel prize for the development of Polymerase chain rection (PCR) in the year 1993

1. Philip Sharp
2. Susumu Tonegava
3. Cesar Milstein
4. Kary Mullis

Q. The instrument used for PCR is called __.

Q. Pick the wrong one out regarding the advantages of PCR.

1. Rapid and easy to perform
2. Sensitive and amplification of DNA from minute samples is possible
3. Robust, making it possible to amplify DNA from degraded samples
4. Prior sequence knowledge is not needed

Q.

Give an example of how PCR is used.

Q. A biology student is performing PCR for the first time. She adds the genomic DNA obtained after isolation along with the corresponding primers in a test tube. She also adds Taq polymerase and deoxyribonucleotides in the tube. The reaction mixture is kept in a water bath that measures 37℃. But DNA amplification does not occur. Why?

Q. Match the following steps of PCR to their respective temperatures:

1. 94$°$C
2. 72$°$C
3. 55$°$C

Q. Which of the following steps is catalysed by Taq polymerase?

1. Denaturation of template DNA
2. Annealing of primers to template DNA
3. Extension of primer end on the template DNA
4. Maintainence of high temperature during PCR

Q.

How is PCR beneficial?

Q. In DNA fingerprinting technique, .......... probe is used for hybridization of DNA fragments.

1. Double stranded RNA
2. Double stranded non-radioactive DNA
3. Single stranded radioactive DNA
4. Single stranded radioactive RNA

Q. The DNA polymerase needed for PCR is obtained from an organism called _______.

1. E.coli
2. Thermus aquaticus
3. Saccharomyces cerevisiae
4. S. aureus

Q. The taq polymerase enzyme is obtained from

1. Thermus aquaticus
2. Thiobacillus ferroxidans
3. Bacillus subtilis
4. Pseudomonas putida

Q. The taq polymerase enzyme is obtained from

1. Thermus aquaticus
2. Thiobacillus ferroxidans
3. Bacillus subtilis
4. Pseudomonas putida

Q.

What is needed for polymerase chain reaction?

Q.

How is the outcome of PCR evaluated?

Q. Annealing process in the PCR needs a temperature of ${72}^{\circ }C.$

1. True
2. False

Q. Crossing over occurs in which of the following stage of cell cycle?

1. Anaphase stage
2. Pachytene stage
3. Diakinesis stage
4. Leptotene stage

Q. DNA polymerase can be obtained from

1. pBR 322
2. Thermus aquaticus
3. Agrobacterium
4. Retro virus

Q. The thermostable enzymes 'Taq' and 'Pfu' isolated from thermophilic bacteria are :

1. Restriction endonucleases
2. DNA ligases
3. DNA polymerases
4. RNA polymerase

Q. Enzyme that is central to the PCR technology is

1. Polymerase
2. Helicase
3. Reverse transcriptase
4. Taq polymerase

Q. Which one is a true statement regarding DNA polymerase

1. It serves as a selectable marker
2. It remains active at high temperature
3. It is isolated from a virus
4. It is used to ligate introduced DNA in recipient cells