1. Photosynthesis

2. Photosynthesis Photosynthesis is the way that plants make food from sunlight –You take in food which is digested and then transferred to cells for use by mitochondria –Plants can’t “eat” so they make food which is then transferred to the mitochondria –Mitochondria then transform the “food energy” into chemical energy

3. Photosynthesis Raw Materials 6 CO 2 + 6 H 2 O Carbon dioxide Water

4. Photosynthesis Source of Energy sunlight

5. Photosynthesis Necessary Catalyst Chlorophyll

6. Photosynthesis → Produces

7. Photosynthesis Products C 6 H 12 O 6 + 6 O 2 Carbohydrate (glucose sugar) Oxygen (to breathe)

8. Photosynthesis 6 molecules of carbon dioxide gas from the atmosphere and 6 molecules of water from the environment will react with sunlight in the presence of chlorophyll to form a molecule of nutrient glucose sugar and release 6 molecules of oxygen gas into the atmosphere OR

9. Photosynthesis 6 CO 2 + 6 H 2 O + light energy → C 6 H 12 O 6 + 6 O 2 Carbon dioxide WaterCarbohydrate Oxygen

10. Photosynthesis Say it in sentence form!

11. Photosynthesis ______ + ______ + ________ → _______ + ____ Carbon dioxide WaterCarbohydrate Oxygen

12. Photosynthesis Some bacteria

13. Photosynthesis Some protists

14. Photosynthesis Most plants

15. Photosynthesis Autotroph: organism that makes its own food (photosynthesis or chemosynthesis) Heterotroph: organism that must consume food

16. Vein Epidermis Mesophyll (site of Chloroplasts And Photo- synthesis) Guard cells Vein Stoma Epidermis

17. Photosynthesis Epidermis: water-proof covering of the surface of the leaf

18. Photosynthesis Stoma: Opening in the leaves –water exits –O 2 exits –CO 2 enters

19. Photosynthesis Stoma: Opening in the leaves –water exits –O 2 exits –CO 2 enters Transpiration

20. Photosynthesis Mesophyll: central layer of cells –contains chloroplast-rich cells –site where most photosynthesis occurs

21. Photosynthesis

22. Photosynthesis 2 sets of reactions:

23. Photosynthesis

24. Photosynthesis –LIGHT DEPENDENT REACTIONS

25. Photosynthesis 2 sets of reactions: –LIGHT DEPENDENT REACTIONS –LIGHT INDEPENDENT REACTIONS (Calvin cycle)

26. Light Dependent Reactions Thylakoids contain pigments (molecules that absorb light)

27. Light Dependent Reactions Thylakoids contain pigments –chlorophyll a absorbs red and blue light reflects green light

28. Light Dependent Reactions Thylakoids contain pigments –carotenoids absorb blue reflect red and yellow light

29. Light Dependent Reactions Thylakoids contain pigments –absorb sunlight energy –give up energized electrons

30. Light Dependent Reactions ATP and NADPH are produced to be used in the next step of photosynthesis: the Calvin cycle (Light Independent Reactions) Requires input of light energy and a water molecule Oxygen is produced and released as a by- product

31. Light Dependent Reactions Light 2e - Electron acceptor Water molecule is split H2OH2O O 2H + + 2e - Photosystem II Electron Transport System Energy is removed from the electrons as they move down the ETC. The energy is used to convert ADP to ATP ADP + P i + Energy → ATP 2e - Electron acceptor Electron Transport System NADPH + H + 2e - NADP + + 2H + Light ATP and NADPH leave thylakoid and enter stroma to be used in the Calvin cycle Oxygen is released as a by-product

32. Light Independent Reactions (Calvin cycle)

33. Calvin cycle Uses ATP and NADPH produced in the light-dependent reactions Also uses CO 2 taken in through stoma Requires no sunlight; occurs around the clock Produces carbohydrate which is used by mitochondria in respiration

34. Photosynthesis

36. Photosynthesis 6 molecules of carbon dioxide gas from the atmosphere and 6 molecules of water from the environment will react with sunlight in the presence of chlorophyll to form a molecule of nutrient glucose sugar and release 6 molecules of oxygen gas into the atmosphere OR

37. Photosynthesis 6 CO 2 + 6 H 2 O + light energy → C 6 H 12 O 6 + 6 O 2 Carbon dioxide WaterCarbohydrate Oxygen