ANATOMY

Detailed explanation-1: -If a cell needs to spend energy to accomplish a task, the ATP molecule splits off one of its three phosphates, becoming ADP (Adenosine di-phosphate) + phosphate. The energy holding that phosphate molecule is now released and available to do work for the cell.

Detailed explanation-2: -Energy is released when an ATP is broken down into ADP and phosphate (a is correct). ATP is the primary energy currency of the cell. This means that cellular processes that require an energy input rely on the energy released from ATP hydrolysis.

Detailed explanation-3: -Energy is released because the products (ADP and phosphate ion) have less energy than the reactants [ATP and water (H2O)]. If the hydrolysis of ATP releases energy, its synthesis (from ADP) requires energy.

Detailed explanation-4: -ATP hydrolysis is the catabolic reaction process by which chemical energy that has been stored in the high-energy phosphoanhydride bonds in adenosine triphosphate (ATP) is released after splitting these bonds, for example in muscles, by producing work in the form of mechanical energy.