5.1.2 Light-Independent Reactions (Calvin Cycle)

• What is another name for the light-independent reactions in photosynthesis?

  Calvin cycle
• The light-independent reactions convert CO_{2} into glucose.
• The light-independent reactions require direct light to occur.

  False
• Which molecule does $CO_{2}$ combine with during carbon fixation in the Calvin cycle?


  RuBP
• During carbon fixation, $CO_{2}$ combines with RuBP to form 3-PGA.
• ATP and NADPH are used during the reduction stage of the Calvin cycle.
• What is 3-PGA converted into during the reduction stage of the Calvin cycle?

  G3P
• The regeneration of RuBP is necessary to continue the Calvin cycle.
• The regeneration of RuBP requires G3P.
• Stages of the Calvin Cycle in the correct order:

  1️⃣ Carbon fixation

  2️⃣ Reduction

  3️⃣ Regeneration of RuBP
• Match the stage of the Calvin Cycle with its key reaction:

  Carbon fixation ↔️ $CO_{2}$ + RuBP $\rightarrow$ 3-PGA

  Reduction ↔️ 3-PGA $+$$ATP +$$NADPH \rightarrow$ G3P

  Regeneration ↔️ G3P $\rightarrow$ RuBP
• The Calvin Cycle is essential for the production of glucose in photosynthesis.
• What is the correct sequence of the three main stages of the Calvin Cycle?

  1️⃣ Carbon fixation

  2️⃣ Reduction

  3️⃣ Regeneration of RuBP
• In the carbon fixation stage, $CO_{2}$ combines with RuBP
• What two energy-carrying molecules are used in the reduction stage of the Calvin Cycle?

  ATP and NADPH
• The regeneration of RuBP is necessary to continue the Calvin Cycle.
• Match the stage of the Calvin Cycle with its key reaction:

  Carbon fixation ↔️ CO_{2}</latex> + RuBP $\rightarrow$ 3-PGA

  Reduction ↔️ 3-PGA + ATP + NADPH $\rightarrow$ G3P

  Regeneration ↔️ G3P $\rightarrow$ RuBP
• What is the end product of the Calvin Cycle?

  Glucose
• Light-independent reactions are also known as the Calvin cycle.
• What does $CO_{2}$ combine with during carbon fixation in the Calvin Cycle?


  RuBP
• What is the correct sequence of key steps in the Calvin Cycle?

  1️⃣ Carbon fixation

  2️⃣ Reduction

  3️⃣ Regeneration of RuBP
• ATP and NADPH are used in the reduction stage to convert 3-PGA into G3P.
• G3P is used to regenerate RuBP in the Calvin Cycle.
• What is the role of light-independent reactions in photosynthesis?

  Convert $CO_{2}$ into glucose
• Match the phase of the Calvin Cycle with its key steps:

  Carbon fixation ↔️ $CO_{2}$ + RuBP $\rightarrow$ 3-PGA

  Reduction ↔️ 3-PGA $+$$ATP +$$NADPH \rightarrow$ G3P

  Regeneration ↔️ G3P $\rightarrow$ RuBP
• What are the three main stages of the Calvin Cycle?

  Carbon fixation, reduction, regeneration
• In the carbon fixation stage, $CO_{2}$ combines with RuBP to form 3-PGA.
• Arrange the stages of the Calvin Cycle in the correct order.

  1️⃣ Carbon fixation

  2️⃣ Reduction

  3️⃣ Regeneration of RuBP
• The reduction stage of the Calvin Cycle uses ATP and NADPH to convert 3-PGA into G3P.
• In the Calvin Cycle, G3P is used to regenerate RuBP.
• Which two molecules are used in the reduction stage of the Calvin Cycle?

  ATP and NADPH
• What enzyme catalyzes the reaction in carbon fixation?

  RuBisCO
• $CO_{2}$ reacts with RuBP to form an unstable 6-carbon intermediate, which splits into two molecules of 3-PGA.
• Match the key reaction in the reduction stage with its products.

  3-PGA $\xrightarrow{ + ATP}$ 1,3-BPG ↔️ 1,3-BPG

  1,3-BPG $\xrightarrow{ + NADPH}$ G3P ↔️ G3P
• What are light-independent reactions also known as?

  Calvin cycle
• Light-independent reactions require direct light but depend on ATP and NADPH.

  False
• In the light-independent reactions, $CO_{2}$ combines with RuBP to form 3-PGA.
• Arrange the phases of the Calvin Cycle in the light-independent reactions in the correct order.

  1️⃣ Carbon fixation

  2️⃣ Reduction

  3️⃣ Regeneration of RuBP
• Which two molecules are used to convert 3-PGA into G3P in the light-independent reactions?

  ATP and NADPH
• G3P is used to regenerate RuBP in the light-independent reactions.