Photosynthesis!!!!

1. Photosynthesis!!!!

2. The Pathway of energy in living organisms cellular respiration Chemical energy for use in the form of ATP photosynthesis Chemical energy stored in glucose, fats, or carbohydrates Light energy from the sun Autotrophs=Organisms that make their own food (usually from photosynthesis). Heterotrophs=Organisms that can't make their own food so they take in food produced by autotrophs (by eating autotrophs or organisms that eat autotrophs)

3. Overview of Cellular Respiration ADP + P + energy The energy released from the catabolism of glucose is used to make ATP from ADP ATP

4. Overview of Photosynthesis The energy from the sun is used to reduce CO2 to produce glucose

5. Figure 10.3 Tracking atoms through photosynthesis

6. Energy flow and chemical recycling in ecosystems Anabolism Catabolism

7. Photoautotrophs: other organisms besides plants can photosynthesize

8. Photosynthesis is divided into two parts The overall reaction in photosynthesis: Light energy 6CO2 12 H2O C6H12O6 6O2 6 H2O + + + + Two components: Light-dependent reactions Light-independent reactions Chemical energy (ATP, NADPH) Chemical energy (ATP, NADPH) Chemical energy (C6 H12O6) Light energy O2 H2O CO2 Energy Harvest Synthesis

9. The energy from light is captured and converted in chloroplasts • Chlorophyll and accessory pigments capture electromagnetic energy by absorbing photons of light.

10. Chlorophyll is found and Photosynthesis takes place in the chloroplasts of plant cells Leaf cross-section Cells containing chloroplasts Leaves contain millions of chloroplasts

11. Chloroplasts are highly structured, membrane-rich organelles Outermembrane Innermembrane Thylakoids Granum Stroma Outer membrane Inner membrane Stroma Granum Thylakoid

12. Figure 10.9 Location and structure of chlorophyll molecules in plants

13. The energy from the sun arrives on earth in the form of light energy, a type of electromagnetic radiation

14. How objects appear different colors White light is a mixture of all wavelengths (and colors) of light White light Green light Is reflected and transmitted We see the Plant as green Red and blue light Is absorbed

15. Figure 10.6 Why leaves are green: interaction of light with chloroplasts

16. The wavelength of light a compound absorbs can be determined by a spectrophotometer

17. Different plant pigments absorb different wavelengths of light. Chlorophyll a Chlorophyll b Carotenoids Amount of light absorbed 400 500 600 700 Wavelength of light (nm)

18. When a photon of light strikes chlorophyll, an electron can be promoted to a higher energy state Electrons can be promoted to discrete high-energy states: e– Blue photons excite electrons to a higher energy state e– Red photons excite electrons to a high-energy state Photons 0 1 2 Energy state of electrons in chlorophyll

19. Figure 10.10 Excitation of isolated chlorophyll by light

20. Photosynthesis • Light Dependent Reaction • Energy from the high energy electron of chlorophyll is used to make ATP and NADPH • Light Independent Reaction (Calvin Cycle) • ATP and NADPH is used to make glucose from CO2

21. Figure 10.4 An overview of photosynthesis: cooperation of the light reactions and the Calvin cycle (Layer 1)

22. Figure 10.4 An overview of photosynthesis: cooperation of the light reactions and the Calvin cycle (Layer 2)

23. Figure 10.4 An overview of photosynthesis: cooperation of the light reactions and the Calvin cycle (Layer 3)