In the ATP Cycle energy is transferred from sunlight or glucose to build from ADP and .

1. ATP

2. Inorganic phosphate (Pi)

Explanation:

Adenosine triphosphate (ATP) is the usable form of energy by the cells of living organisms. During the light reaction of photosynthesis, energy from sunlight (solar energy) is converted to ATP in order to power the Calvin cycle stage. Also during cellular respiration, energy stored in glucose molecule is transferred to ATP.

The processes by which this synthesis of ATP from ADP (Adenosine diphosphate) occurs is called oxidative phosphorylation and chemiosmosis. Energy is stored in the ATP molecule when ADP combines with inorganic phosphate (Pi).