Final answer:
The hydrolysis of ATP is crucial because it provides energy for cellular processes. The reverse reaction of synthesizing ATP from ADP and Pi is also essential, as it uses energy coupling to facilitate endergonic reactions necessary for cell function.
Step-by-step explanation:
The hydrolysis of ATP is a crucial biological process where ATP (adenosine triphosphate) is broken down into ADP (adenosine diphosphate) and an inorganic phosphate ion (Pi), along with the release of free energy. This reaction is represented by the chemical equation: ATP + H₂O → ADP + Pi + energy. The reason the hydrolysis of ATP is useful is option A: ATP hydrolysis provides energy for cellular processes. This free energy released is vital for a multitude of cellular activities, including molecular synthesis, mechanical work, and active transport, such as with the sodium-potassium pump (Na+/K+ pump).
The reverse reaction involves the synthesis of ATP from ADP and Pi which requires energy input, likening ATP to a rechargeable battery within cellular metabolism. Energy coupling is a strategy by which cells use the energy released from exergonic reactions, such as ATP hydrolysis, to drive endergonic reactions, which are necessary for cellular function and maintenance.