How is ATP recycled?

The cyclic conversion of ATP to ADP and then back again to ATP is known as the ATP cycle. During the process, the terminal phosphate from the three phosphate molecules in ATP is broken by breaking its phosphoanhydride bond, converting into ADP. Within the mitochondria, energy is used to attach one phosphate group to an ADP molecule to generate an ATP molecule. Through this mechanism, ATP is constantly recycled in order to meet the cell's energy requirement. Approximately 7.3 kcal/mol energy is released by the hydrolysis of one ATP. This free energy can be transferred to other molecules in order to make unfavorable reactions in cells favorable. On a side note, a phosphate bond can also be removed in ADP to create AMP. AMP can then be recycled and converted into ADP or ATP by creating new phosphoanhydride bonds. Thus, AMP, AMP, and ATP are consistently converted into different forms throughout the overall process.