Free PCR Principles & Techniques Questions and Answers

Question 1

What is the primary purpose of PCR in molecular biology?

Accepted Answer

To amplify DNA segments.

Answer

To cut DNA into fragments.

Answer

To sequence RNA.

Answer

To analyze protein structure.

Question 2

Which enzyme is essential for the DNA synthesis phase of PCR?

Accepted Answer

Taq polymerase

Answer

DNA ligase

Answer

RNA polymerase

Answer

Helicase

Question 3

What is the role of primers in PCR?

Accepted Answer

Start DNA synthesis at specific sites

Answer

Act as enzymes

Answer

Bind to proteins

Answer

Break DNA strands

Question 4

Which step in PCR involves the separation of DNA strands?

Accepted Answer

Denaturation

Answer

Annealing

Answer

Elongation

Answer

Transcription

Question 5

What happens during the annealing step in PCR?

Accepted Answer

Primers bind to target DNA

Answer

DNA strands are separated

Answer

New DNA strands are synthesized

Answer

RNA is transcribed

Question 6

Which of the following is required in a PCR reaction mixture?

Accepted Answer

Primers, template, nucleotides, buffer, and Taq polymerase

Answer

Lipids

Answer

ATP only

Answer

Antibodies

Question 7

Why is Taq polymerase preferred in PCR?

Accepted Answer

It is heat-stable and synthesizes DNA

Answer

It binds RNA.

Answer

It functions at low pH.

Answer

It denatures DNA.

Question 8

What is the typical number of cycles in a standard PCR run?

Accepted Answer

25–35

Answer

5–10

Answer

15–20

Answer

40–60

Question 9

What is the function of the buffer solution in PCR?

Accepted Answer

Stabilizes pH and ionic strength

Answer

Prevents evaporation

Answer

Provides oxygen

Answer

Stains DNA