Assertion: The stickiness of ends produced by restriction endonuclease faciliates the action of DNA polymerase
Reason :It helps in joining the two DNA strands

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion
B. It both Assertion & Reason are True but Reason is not a correct explanation of the Assetion
C. If Assertion is True but the Reason is False
D. If both Assertion & Reason are false

Answer

To solve the assertion-reason question, let's break down the components step by step.

### Step 1: Understand the Assertion
The assertion states: "The stickiness of ends produced by restriction endonuclease facilitates the action of DNA polymerase."

- **Explanation**: Restriction endonucleases, such as EcoRI, cut DNA at specific sequences, creating "sticky ends." These sticky ends are overhanging sequences of DNA that can easily anneal to complementary sequences. This stickiness is crucial for the action of DNA polymerase, as it allows the enzyme to effectively bind and extend the DNA strands.

### Step 2: Understand the Reason
The reason states: "It helps in joining the two DNA strands."

- **Explanation**: While the sticky ends do facilitate the binding of DNA strands, the role of DNA polymerase is not to join the two strands directly. Instead, DNA polymerase synthesizes new DNA by adding nucleotides to a growing strand. The actual joining of the two DNA strands is typically done by another enzyme called DNA ligase.

### Step 3: Evaluate the Truth of Each Statement
- **Assertion**: True. The stickiness of ends indeed facilitates the action of DNA polymerase.
- **Reason**: False. The reason provided does not accurately describe the role of DNA polymerase.

### Step 4: Determine the Correct Option
Based on the evaluations:
- The assertion is true, but the reason is false. Therefore, the correct option is:
**Option C: Assertion is true but reason is false.**

### Final Answer
The correct answer is Option C: Assertion is true but reason is false.

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