Question

Which enzyme cuts the DNA at specific site?

• A. Ligase
• B. Exonuclease
• C. Endonuclease
• D. Polymerase

Hint:

Restriction endonucleases are widely used in genetic engineering to cut DNA at precise recognition sequences.

Answer 1

The Correct Option is C

Step 1: Understanding enzymes related to DNA.
Different enzymes perform specific roles in DNA manipulation: ligase joins DNA fragments, exonuclease removes nucleotides from the ends, endonuclease cuts DNA within the strand, and polymerase synthesizes DNA.

Step 2: Identifying the correct enzyme.
- (A) Ligase: Joins fragments of DNA, does not cut.
- (B) Exonuclease: Removes nucleotides from the ends of DNA, not at a specific site.
- (C) Endonuclease: Cuts DNA at specific sites within the molecule, including restriction endonucleases.
- (D) Polymerase: Synthesizes new DNA strands, not responsible for cutting.

Step 3: Conclusion.
The correct answer is (C) Endonuclease, as it cuts DNA at specific sites.