What is the primary high-energy molecule that supplies energy to cells?

The primary high-energy molecule that supplies energy to cells is ATP, or adenosine triphosphate. ATP plays a crucial role in cellular metabolism, serving as the main energy currency of the cell. When cells require energy for various functions, such as muscle contraction, nutrient transport, and enzymatic reactions, they break down ATP into ADP (adenosine diphosphate) and inorganic phosphate. This process releases energy that can be utilized for cellular activities.

ATP is specifically structured to store and release energy efficiently due to its high-energy phosphate bonds. The hydrolysis of these bonds provides the energy needed for cellular processes.

The other molecules listed, such as ADP, AMP, and GTP, also play roles in cellular processes but are not the primary energy carriers. ADP and AMP are by-products of ATP metabolism, whereas GTP functions in specific signaling pathways and protein synthesis but does not serve the general energetic needs of cells in the same broad manner as ATP. Thus, ATP stands out as the fundamental energy source for cellular activity.