1. Chapter 10
Photosynthesis

2. Overview CO2 fixed to form organic molecules
Organic molecules combined to produce glucose
O2 released into the atmosphere

3. Significance Ultimate source of free oxygen
Ultimate source of food for consumers
Removes waste CO2 from the atmosphere

4. Organisms that photosynthesize
Purple sulfur bacteria
Cyanobacteria
Eukaryotic single-celled algae
Multicellular algae
Plants

5. Chloroplasts Found in all eukaryotic photosynthetic organisms
Thylakoid membrane
Grana
Stroma
Double membrane

6. Main Pathways Light dependent Light independent
Occurs within thylakoid membrane
Produces ATP, NADPH, O2
Light independent
Uses ATP, NADPH and CO2
Produces sugars

7. Light Dependent Pathway

8. Visible Light

9. Absorption Spectrum

10. Light Independent Pathway
Calvin-Benson Pathway
Stroma of chloroplast
3 CO2 molecules enter and combine with Ribulose bisphosphate
Enzyme- Rubisco
Glyceraldehyde 3 phosphate produced

11. Alternate Carbon Fixation Schemes
C4 Plants
CAM Plants
Both conserve water by storing carbon during cooler times of the day

12. C 4 Pathway Distinctive leaf anatomy Phosphoenol pyruvate- 3 C
Carboxylated- higher afinity for CO2 than Rubisco
Concentrates CO2 within Mesophyll cells
OAA- 4C
Malate
Donate CO2 to Calvin Cycle

13. CAM Crassulacean family of plants (succulents)
Crassuslacean Acid Metabolism
Stomata stay closed all day
Accumulates CO2 at night for use during the day
Similar to C4 but uses different organic acids

14. Compare C3 C4 and CAM