Assertion: Restriction endonucleases produces overhanging stretches called sticky ends on each DNA strand
Reason :Restriction enzymes cut the strand of DNA a little away from the centre of pallindrome sites

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 it down step by step.

### Step 1: Understand the Assertion
The assertion states that "Restriction endonucleases produce overhanging stretches called sticky ends on each DNA strand."

- **Explanation**: Restriction endonucleases are enzymes that cut DNA at specific sequences known as recognition sites. When they cut the DNA, they can leave overhanging ends, which are referred to as "sticky ends." These sticky ends can easily pair with complementary sequences of DNA, facilitating the process of recombination.

### Step 2: Understand the Reason
The reason states that "Restriction enzymes cut the strand of DNA a little away from the center of palindrome sites."

- **Explanation**: Palindrome sites in DNA are sequences that read the same forwards and backwards on complementary strands. Restriction enzymes cut these palindromic sequences slightly away from the center, which results in the formation of sticky ends. If the enzyme cut directly at the center, it would produce blunt ends, which are not as effective for recombination.

### Step 3: Analyze the Relationship Between Assertion and Reason
Now, we need to determine if both the assertion and reason are true and if the reason correctly explains the assertion.

- Both the assertion and reason are indeed true. The assertion is correct because restriction endonucleases do produce sticky ends, and the reason is correct because cutting away from the center of palindrome sites is what leads to the formation of these sticky ends.

### Step 4: Conclusion
Since both the assertion and reason are true, and the reason correctly explains the assertion, the correct answer is:

**Option A**: Both assertion and reason are true, and the reason is the correct explanation of the assertion.

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