Light-dependent reaction

• What is photolysis of water?

  • light energy absorbed by chlorophyll and splits water into oxygen, H+ and electrons
  • H+ picked up by NADP to form NADPH
  • oxygen either used in respiration or diffuses out of leaf through stomata
  • electrons passed along chain of electron carrier proteins
• What is photoionisation of chlorophyll?

  • light energy absorbed by chlorophyll resulting in electrons becoming excited and raising energy levels
  • chlorophyll becomes ionised by light
  • energy released from electrons is used to ATP and reduced NADP
• What is chemiosmosis?

  • electrons that gained energy move along series of proteins embedded within thylakoid membrane
  • energy released from electrons used to pump protons across chloroplast membrane
  • protons pass through ATP synthase by facilitated diffusion, producing ATP
  • protons combine with NADP to become reduced NADP