Answer:
The correct answer would be C. With an input of energy, ADP combines with a phosphate group to become ATP.
Inorganic phosphorus and energy are added to adenosine diphosphate (ADP) in order to convert it to adenosine triphosphate (ATP).
This reaction is usually catalyze by the enzyme ATP synthase. It present in inner membrane of mitochondria of the cell as well as in the thyllakoid membrane in chloroplast.
ATP synthase uses the energy provided by chemiosmosis i.e. flow of protons down the gradient across the membrane through this enzyme. Proton gradient is formed either by photosynthesis or by cellular respiration.
ADP + inorganic phosphate (Pi) + energy → ATP + H₂O
ATP is used as the energy currency of the cell which breaks down to release inorganic phosphate group and energy which is used in various metabolic processes.
