Question

Restriction endonucleases are used as

• A. Molecular build up at nucleotides
• B. Molecular degradation to break up a DNA
• C. Molecular knives for cutting DNA at specific sites
• D. Molecular cement to combine DNA sites

Answer 1

Answer: (C)

Molecular knives for cutting DNA at specific sites

Restriction endonucleases are enzymes that cleave the sugar-phosphate backbone of DNA. In most practical settings, a given enzyme cuts both strands of duplex DNA within a stretch of just a few bases. Several thousand different restriction endonucleases have been isolated, which collectively exhibit a few hundred different sequence (substrate) specificities.

Thus, the correct answer is option C.