Answer: ATP releases energy when it converts to ADP .
Explanation:
During energy needs, the body cells directs the loss of a phosphate group (Pi) from ATP (Adenosine triphosphate) to yeild ADP (adenosine Diphosphate), and a further loss will yield AMP (adenosine monophosphate). For each loss energy is also released when a phosphate is removed
The reaction involves the addition of water, so it is a hydrolytic reaction, and is catalyzed by enzymes of the mitochondria, and is represented as the equation below:
ATP + H2O → ADP + Pi + free energy