• Photosynthesis occurs in two stages: the?light-dependent stage, which takes place in the?thylakoids, and the?light-independent stage, which takes place in the?stroma
• During the?light-dependent?stage of photosynthesis:
  • Reduced NADP?is produced when hydrogen ions combine with the?carrier molecule NADP?using electrons from the?photolysis?of water
  • ATP?is produced (from ADP and Pi?by?ATP synthase?in a process called?photophosphorylation?(ADP + Pi?→ ATP)
  • Photophosphorylation uses the?proton (H+) gradient?generated by the photolysis of water
  • Energy from?ATP?and?hydrogen from reduced NADP?are passed from the light-dependent stage to the light-independent stage of photosynthesis
• The energy and hydrogen are used during the?light-independent?reactions (known collectively as the?Calvin cycle) to produce complex organic molecules, including (but not limited to)?carbohydrates, such as:
  • Starch?(for storage)
  • Sucrose?(for translocation around the plant)
  • Cellulose?(for making cell walls)

Photosynthesis occurs in two, closely-linked stages: the light-dependent stage, which takes place in the thylakoids, and the light-independent stage, which takes place in the stroma