1. Nature of Light ä Electromagnetic energy ä Both wavelike & particle- like behavior

4. Nature of Light ä Photon - packet (quantum) of energy ä Energy of photon inversely proportional to wavelength

5. Nature of Light ä Sun radiates full spectrum of wavelengths ä Atmosphere filters most out except visible light

7. Pigments ä Substances which absorb visible light ä Color seen is wavelengths most reflected or transmitted

8. Chlorophyll ä Blue & red are most effectively absorbed ä Green reflected & transmitted

10. Absorption Spectrum ä Graph of wavelengths absorbed by a pigment ä Read by spectrophotometer

12. Action Spectrum ä Graph of wavelength vs. rate of photosynthesis ä Effectiveness of wavelength at driving photosynthesis

14. Chlorophyll ä 2 types: chlorophyll a & chlorophyll b ä Only chlorophyll a participates directly in photosynthesis

16. Chlorophyll a ä Absorption spectrum doesn’t match action spectrum ä Other pigments function as accessory pigments

18. Accessory Pigments ä Absorb light and transfer energy to chlorophyll a ä Each pigment has unique absorption spectrum

19. Accessory Pigments ä Chlorophyll b ä yellow-green pigment ä Carotenoids ä yellow & orange pigments

21. Photosynthesis ä Net reaction: 6CO 2 + 6H 2 O + light 6O 2 + C 6 H 12 O 6

22. Photosynthesis 6CO 2 + 6H 2 O + Energy C 6 H 12 O 6 + 6O 2 loses H; is oxidized gains H; is reduced

24. Source of O 2 ä From H 2 O or CO 2 ? ä 1) Bacteria that use H 2 S rather than H 2 O produce sulfur as byproduct

25. Source of O 2 ä 2) Isotope ( 18 O) tracer studies ä H 2 O labeled, O 2 released labeled ä CO 2 labeled, O 2 released not labeled

26. Source of O 2 ä Photosynthesis extracts H from H 2 O & excretes O 2 as waste

27. Photosynthesis ä Occurs in two stages: Light Reactions Calvin Cycle