DNA is cut at specific points during the production of recombinant $DNA$ using which of these enzymes?

• A. Helicase
• B. $DNA$ polymerase
• C. Ligase
• D. Restriction enzymes

Answer: (D)

Verified step by step guidance

1. Understand the role of restriction enzymes: Restriction enzymes are proteins that cut DNA at specific sequences, known as recognition sites. These enzymes are crucial in the production of recombinant DNA as they allow for precise cutting and manipulation of DNA fragments.
2. Differentiate between the enzymes listed: Helicase unwinds the DNA double helix, DNA polymerase synthesizes new DNA strands, and ligase joins DNA fragments together. None of these enzymes are responsible for cutting DNA at specific points.
3. Identify the function of restriction enzymes: Restriction enzymes recognize specific, short nucleotide sequences in the DNA and make cuts at or near these sites. This ability to cut DNA at precise locations is essential for genetic engineering and molecular cloning.
4. Consider the application in recombinant DNA technology: In recombinant DNA technology, restriction enzymes are used to cut both the DNA of interest and the vector DNA, allowing for the insertion of the DNA fragment into the vector.
5. Conclude with the correct enzyme: Based on the function and application of restriction enzymes, they are the correct choice for cutting DNA at specific points during the production of recombinant DNA.