Energy Carriers in Photosynthesis

Photosynthesis and respiration involve the movement of electrons (e⁻) and hydrogen ions (protons or H⁺).

• Oxidation: A molecule loses electrons.
• Reduction: A molecule gains electrons.

ATP (Adenosine Triphosphate)

• ATP is an energy carrier.
• It traps energy and carries it from where it's produced to where it's needed.

ADP (Adenosine Diphosphate)

• ADP is a low energy molecule.
• When ADP combines with a phosphate (P), energy is trapped in the bond, forming ATP.
• When this bond is broken, the stored energy is released.

NADP⁺ (Nicotinamide Adenine Dinucleotide Phosphate)

• NADP⁺ is involved in photosynthesis.
• When NADP⁺ gains 2e⁻ and an H⁺ ion, it becomes NADPH.

NADPH

• NADPH is a high-energy electron and proton carrier.
• It transports electrons and H⁺ ions to where they are needed in the cell.
• NADPH uses its electrons and H⁺ ions to make glucose in photosynthesis.