Download Light Independent Photosynthesis

Light Independent Photosynthesis:
The Calvin-Benson Cycle
 The cyclical reactions that convert CO2 into carbohydrates
occur in the stroma of the chloroplasts.
 The Calvin cycle can be divided into three Phases:
 Carbon fixation - 3 molecules of CO2 are added to 3
molecules an existing 5-Carbon ribulose 1,5 –
bisphosphate (RuBP) to form 3 unstable 6-C molecules
that instantly splits into six 3-Carbon molecules called
3-phosphoglycerate (PGA). Rubisco is the very large
enzyme that catalyzes the reaction very slowly. It is
found in large quantities in a plant leaf so is actually the
most abundant protein on earth.
 Reduction reactions - basically the reverse of
glycolysis: NADPH is used to change six molecules of
PGA into six molecules of G3P. One of the G3P is
removed and used to make carbohydrates.
 Regeneration of RuBP – three molecules of ATP are
used to provide energy to transform five molecules of
G3P to three molecules of RuBP.
The role of Glyceraldehyde 3-phosphate G3P
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Where and at what stage of photosynthesis is G3P made?
What products are made with G3P?
What is the extra G3P is for and where is it stored?
How is the Excess G3P transported around the plant and what is it used for?
Alternate ways of Carbon Fixation
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What does C3 metabolism mean? What types of plants perform it?
What enzyme is used to fix CO2 during the Calvin cycle?
What is photorespiration? Why is it hazardous for plants?
Describe C4 plants and C4 photosynthesis in detail including a good diagram.
What does CAM stand for?
Describe CAM plants and the CAM form of carbon fixation.
The role of Glyceraldehyde 3-phosphate G3P
5.
6.
7.
8.
Where and at what stage of photosynthesis is G3P made?
What products are made with G3P?
What is the extra G3P is for and where is it stored?
How is the Excess G3P transported around the plant and what is it used for?
Alternate ways of Carbon Fixation
7. What does C3 metabolism mean? What types of plants perform it?
8. What enzyme is used to fix CO2 during the Calvin cycle?
9. What is photorespiration? Why is it hazardous for plants?
10. Describe C4 plants and C4 photosynthesis in detail including a good diagram.
11. What does CAM stand for?
12. Describe CAM plants and the CAM form of carbon fixation.