How is ATP used?

ATP can be used to either store energy for future reactions, or to be used in reactions where energy is required by the cell. When animals eat food, the energy from the food is stored as ATP in their bodies. Plants also capture and store energy during photosynthesis in ATP molecules. In simpler terms, ATP acts as an energy currency of the cell, as it can either be spent or saved.

When a cell needs to spend energy to carry out a certain function, one of the three phosphate groups detaches from ATP, becoming ADP+ phosphate. The energy then becomes available to do tasks for the cell. When the cell has extra energy, it stores the energy by attaching a free phosphate to ADP to become ATP again. This process repeats itself constantly. The processes ATP is involved in include muscle contraction, ion transport, substrate phosphorylation, chemical synthesis, and nerve impulse propagation. In conclusion, ATP has no one single use, and is important for many processes in biology.