Question

Which of the following molecules is not required for a PCR reaction?

1) DNA
2) Ligase
3) Primer
4) DNTPs

Answer 1

Ligase is not required in a PCR reaction. Instead, PCR requires DNA, primers, DNA polymerase, and dNTPs to amplify a specific section of DNA. The correct multiple-choice option is (2).

Step-by-step explanation:

In a Polymerase Chain Reaction (PCR) setup, certain components are essential for the reaction to proceed. These include: a DNA template from which to amplify a new piece of DNA, primers that initiate the DNA synthesis, DNA polymerase enzyme to assemble the new DNA strands, and dNTPs (deoxynucleotide triphosphates) which are the building blocks of the DNA strand. Among the options provided, ligase is not required for a PCR reaction. Ligase is used during molecular cloning to repair the phosphodiester backbone of DNA fragments that have been joined together, not during PCR amplification.

The correct multiple-choice option is (2).