LIR photosynthesis

• What is the second stage of photosynthesis called?

  Light independent reaction
• What is another name for the light independent reaction?

  Calvin cycle
• Where does the light independent reaction occur?

  In the stroma of chloroplasts
• What enzyme catalyzes a key stage in the Calvin cycle?

  Rubisco
• How does temperature affect the Calvin cycle?

  It affects the rate due to enzyme sensitivity
• What are the key molecules involved in the Calvin cycle?

  Carbon dioxide, ATP, and reduced NADP
• What is the end product of the Calvin cycle?

  Hexose sugar
• What happens to ATP during the Calvin cycle?

  It is hydrolyzed to release energy
• What does reduced NADP donate in the Calvin cycle?

  A hydrogen atom
• What does GP stand for in the Calvin cycle?

  Glycerate 3-phosphate
• What is the first step in converting GP to TP?

  Hydrolysis of ATP
• What is the significance of removing one carbon atom from TP?

  It allows for hexose sugar formation
• What must happen to regenerate RuBP?

  ATP is required
• Why does AQA use the term organic substances?

  To include various carbon-containing compounds
• What are limiting factors in photosynthesis?

  Conditions that reduce the rate of photosynthesis
• How does temperature act as a limiting factor?

  It affects enzyme activity in reactions
• What happens to carbon dioxide concentration at high levels?

  It is no longer a limiting factor
• How does light intensity affect photosynthesis?

  It is required for light dependent reactions
• Why is knowledge of limiting factors important for farmers?

  It helps optimize plant growth conditions
• What must farmers consider when using artificial conditions?

  Cost-effectiveness of inputs versus profits
• What is the most common product of the Calvin cycle?

  Glucose
• What are the steps of the Calvin cycle?

  1. Carbon dioxide enters and reacts with RuBP.
  2. Rubisco catalyzes the reaction.
  3. Produces two molecules of GP.
  4. GP is converted to TP using ATP and reduced NADP.
  5. One carbon atom is removed to form organic substances.
  6. Remaining TP regenerates RuBP using ATP.
• What are the effects of temperature, carbon dioxide concentration, and light intensity on photosynthesis?

  • Temperature affects enzyme activity.
  • Low carbon dioxide limits the Calvin cycle.
  • Light intensity is crucial for light dependent reactions.
  • High levels of carbon dioxide and light intensity can become non-limiting.
• What are the potential products of glucose in plants?

  • Disaccharides (e.g., sucrose)
  • Polysaccharides (e.g., cellulose, starch)
  • Other organic compounds (e.g., glycerol for lipids)