Question

Which of the following steps are related to polymerase chain reaction (PCR)?
(A) Extension
(B) Annealing
(C) Propagation
(D) Denaturation

• A. (A), (B) and (D) only
• B. (A), (B) only
• C. (A), (B), (C) and (D)
• D. (B), (C) and (D) only

Hint:

PCR involves four main steps: Denaturation, Annealing, Extension, and Propagation, each crucial for amplifying DNA segments.

Answer 1

The Correct Option is C

Step 1: Understanding PCR.
Polymerase Chain Reaction (PCR) is a molecular biology technique used to amplify a specific segment of DNA. It consists of a series of temperature-dependent steps.
Step 2: Key steps in PCR.
- Extension (A): During this step, the DNA polymerase synthesizes a new DNA strand complementary to the template strand. This occurs at an optimal temperature for the polymerase enzyme to function.
- Annealing (B): In this step, the primers (short DNA sequences) bind (anneal) to their complementary sequences on the single-stranded DNA template. This step occurs at a lower temperature.
- Propagation (C): This term generally refers to the replication process, but in PCR, it can refer to the amplification of the DNA segment in the presence of polymerase during the extension step.
- Denaturation (D): The DNA template is heated to a high temperature to break the hydrogen bonds between the complementary DNA strands, making them single-stranded.
Step 3: Conclusion.
All four steps (Extension, Annealing, Propagation, and Denaturation) are integral parts of the PCR process.
Final Answer: \[ \boxed{\text{The correct answer is (3) (A), (B), (C) and (D).}} \]