Skip to main content
Indietro

Photosynthesis: Light Reactions and Calvin Cycle

I pulsanti di controllo sono stati cambiati in modalità "navigazione".
1/14

Termini in questo insieme (14)

  • Where do the light reactions of photosynthesis occur?
    In the thylakoid membrane of the chloroplast.
  • What are the main inputs and outputs of the light reactions?
    Inputs: Light energy and H₂O. Outputs: ATP, NADPH, and O₂ (by-product).
  • What is the role of Photosystem II in the light reactions?
    Photosystem II absorbs light, energizes electrons, and splits water to replace electrons, releasing O₂ and H⁺.
  • What happens to electrons after Photosystem II?
    Electrons pass down an electron transport chain, pumping H⁺ into the thylakoid space.
  • What is the function of Photosystem I?
    Photosystem I re-energizes electrons before they reduce NADP⁺ to NADPH.
  • How is ATP produced in the light reactions?
    H⁺ ions flow back through ATP synthase via chemiosmosis, producing ATP.
  • Where does the Calvin cycle take place?
    In the stroma of the chloroplast.
  • What is the first step of the Calvin cycle?
    Carbon fixation: Rubisco attaches CO₂ to RuBP, forming two 3-carbon 3-PGA molecules.
  • What happens during the reduction phase of the Calvin cycle?
    ATP and NADPH convert 3-PGA into G3P, a 3-carbon sugar.
  • What is the regeneration step in the Calvin cycle?
    Most G3P is rearranged using ATP to regenerate RuBP, allowing the cycle to continue.
  • How many G3P molecules are produced from 3 CO₂ molecules in the Calvin cycle?
    6 G3P molecules are produced; 1 G3P exits to make sugars, and 5 regenerate RuBP.
  • What sugars are produced from G3P?
    G3P is converted into glucose, sucrose, and starch.
  • What is the relationship between light reactions and the Calvin cycle?
    Light reactions produce ATP and NADPH that power the Calvin cycle; the Calvin cycle uses chemical energy to build sugars.
  • What is the overall chemical equation for photosynthesis?
    6 CO₂ + 6 H₂O + light energy → C₆H₁₂O₆ + 6 O₂.