The energy for DNA synthesis comes most directly from
A) deoxyribose
B) dNTPs
C) PPi
D) NADH
E) ribose

Question

Quizplus · Accepted Answer

The energy for DNA synthesis comes from the nucleoside triphosphates (dNTPs), which are used as substrates for the DNA polymerase enzyme. As each nucleotide is added to the growing DNA strand, two of the phosphate groups are cleaved off, releasing energy that is used to drive the polymerization reaction. The released phosphates combine to form inorganic pyrophosphate (PPi), which is hydrolyzed by pyrophosphatase to provide additional energy for the reaction. However, it is the dNTPs themselves that provide the primary source of energy for DNA synthesis. The other choices (deoxyribose, NADH, and ribose) are components of nucleotides or other cellular molecules, but they are not directly involved in providing energy for DNA synthesis.

The Energy for DNA Synthesis Comes Most Directly from