Question

In genetic engineering DNA ligase is used for ........

• A. polymerase chain reaction
• B. fragmentation of DNA
• C. joining the desired gene into vector
• D. reverse transcription

Hint:

DNA ligase is an essential enzyme in genetic engineering that helps in joining DNA fragments, such as inserting genes into vectors.

Answer 1

The Correct Option is C

Step 1: Understanding the role of DNA ligase.
DNA ligase is an enzyme used in genetic engineering to join DNA fragments together. Specifically, it is used to insert the desired gene into a vector, forming recombinant DNA.
Step 2: Analyzing the options.
(A) polymerase chain reaction: Incorrect — DNA ligase is not used in the polymerase chain reaction (PCR); instead, DNA polymerase is used in PCR.
(B) fragmentation of DNA: Incorrect — DNA ligase does not fragment DNA; it helps to join DNA fragments.
(C) joining the desired gene into vector: Correct — DNA ligase is used to ligate (join) the desired gene into a vector.
(D) reverse transcription: Incorrect — Reverse transcription is performed by the enzyme reverse transcriptase, not DNA ligase.
Step 3: Conclusion.
The correct answer is (C) joining the desired gene into vector, as DNA ligase is used for this purpose in genetic engineering.