1. Chapter 7
Capturing Energy
Photosynthesis

2. Photosynthesis
Solar energy is stored in chemical bonds

3. Cellular Respiration
Energy from chemical bonds extracted and used

4. Energy stored
Photosynthesis
Energy extracted
Cellular respiration

5. Photosynthesis

6. Photosynthesis

7. Photosynthesis
Photosynthesis

8. Photosynthesis Light energy Photo- synthesis Carbon dioxide Water
Glucose
Oxygen
gas 8

9. Photosynthesis 6CO2 + 12 H20 glucose + 6H20 + 6O2 Low energy molecules

10. Photosynthesis
6CO H20
Light energy
glucose + 6H20 + 6O2

11. Photosynthesis 6CO2 + 12 H20 glucose + 6H20 + 6O2
Light energy caputured
glucose + 6H20 + 6O2
Energy stored here

12. Cell respiration 6CO2 + 12 H20 glucose + 6H20 + 6O2
Energy released and used
High energy molecule
glucose + 6H20 + 6O2

13. Electromagnetic radiation

14. Visible Light

16. Wavelengths absorbed by plants

18. Photosynthesis: 2 parts
*light reactions
*Calvin cycle

19. Photosynthesis: 2 parts
*light reactions
Energy collected
*Calvin cycle
Energy used

20. Primary photoevent

21. Energy out
Energy in

23. Photosynthesis: Light Reactions
Two photosystems: I and II
II. I.

24. II. Source of electrons Electron excited
Photosynthesis: Light Reactions
Source of electrons
Electron excited

25. II. Energy harvested from excited electron
Photosynthesis: Light Reactions
Energy harvested from excited electron

26. Electron transport system
Electrons fall ‘down hill’ giving up energy

27. II. *ATP *Excited electron Energy at end of photo-system II
Photosynthesis: Light Reactions
Energy at end of photo-system II
*ATP
*Excited electron

28. Photosynthesis: Light Reactions
Source of electrons I.

29. Energy from excited electron stored here
Photosynthesis: Light Reactions
Energy from excited electron stored here

30. Photosynthesis: Light Reactions
Energy in

31. Photosynthesis: Light Reactions
Energy stored

32. Calvin Cycle
*Energy from collected in Photosystems is tied up in glucose

33. The Calvin Cycle
Convert energy from light reaction into sugars

34. The Calvin Cycle
Low energy raw material: CO2

35. The Calvin Cycle
Energy from light reactions

36. The Calvin Cycle Convert energy from light reaction into sugars
glucose

38. Photosynthesis and cellular respiration