Question

Which of the following is a difference between the mechanisms of DNA polymerase and RNA polymerase?

A. The direction of polymerization for DNA polymerase is 5′ to 3′, but RNA polymerase is 3′ to 5′.

B. DNA polymerase uses DNA as a template for making DNA copies; RNA polymerase uses RNA as a template for making RNAs.

C. DNA polymerase uses the energy from the hydrolysis of the nucleotide triphosphates to drive the reaction; RNA polymerase uses reduced electron carriers.

D. DNA polymerase needs a base-paired 3′ −OH for a polymerization reaction to occur; RNA polymerase can polymerize two nucleotides without a base-paired 3′ −OH.

Answer 1

The main difference between DNA polymerase and RNA polymerase is the direction of polymerization. DNA polymerase adds nucleotides in the 5' to 3' direction, while RNA polymerase adds nucleotides in the 3' to 5' direction.

Step-by-step explanation:

The main difference between DNA polymerase and RNA polymerase is the direction of polymerization. DNA polymerase adds nucleotides in the 5' to 3' direction, while RNA polymerase adds nucleotides in the 3' to 5' direction.

For DNA polymerase, the 3' -OH group of the growing strand acts as a nucleophile to attack the phosphorous of the incoming nucleotide triphosphate (NTP), forming a phosphodiester bond. RNA polymerase, on the other hand, can polymerize two nucleotides without a base-paired 3' -OH.

In terms of templates, DNA polymerase uses DNA as a template for making DNA copies, while RNA polymerase uses DNA as a template for making RNA copies.