Substrate-Level Phosphorylation Transfers Phosphate Groups Directly from ____ to ADP

Question

Substrate-level phosphorylation transfers phosphate groups directly from ____ to ADP.  
A) a substrate
B) coenzymes
C) the electron transfer chain
D) ATP
E) the citric acid cycle

Accepted Answer

Substrate-level phosphorylation occurs when a phosphate group is transferred from a substrate directly to ADP, resulting in the formation of ATP. This process does not involve the electron transport chain, coenzymes or the citric acid cycle.