AP BIOLOGY

Detailed explanation-1: -ATPases are a group of enzymes that catalyze the hydrolysis of a phosphate bond in adenosine triphosphate (ATP) to form adenosine diphosphate (ADP). They harness the energy released from the breakdown of the phosphate bond and utilize it to perform other cellular reactions.

Detailed explanation-2: -Through metabolic processes, ATP becomes hydrolyzed into ADP, or further to AMP, and free inorganic phosphate groups. The process of ATP hydrolysis to ADP is energetically favorable, yielding Gibbs-free energy of-7.3 cal/mol.

Detailed explanation-3: -The ATP is hydrolyzed into ADP and inorganic phosphate (Pi) by the enzyme ATPase.

Detailed explanation-4: -At the same time, extracellular ATP, whose concentration is known to be enhanced during ischemia, is actively broken down to adenosine through the pathway ATP–> ADP–> AMP–> adenosine, catalysed by the well characterized ecto-enzyme cascade system.