1. Photosynthesis

2. How is Sugar Made? Photosynthesis Making sugar from sunlight
Like a two act play
Act I: Light Reaction “photo”
Act II: Calvin Cycle “synthesis”

3. Setting
Chloroplast
Located in the leaves of plant

4. Chloroplast

5. Cast Chlorophyll- a light catching pigment CO2 – an inorganic gas
H2O - water
ATP – molecule that stores & releases energy
NAD+, NADP+ & FADH – Carry electrons around to make energy

6. Overall Plot
H2O and CO2 will come together in the chloroplast to produce a molecule of glucose
In the process there will be a waste product produced,
oxygen

7. Plot as a Formula

8. Funding For this Performance
Sunlight
Without the generous donation of energy from the sun this performance would not be possible

9. Act One Light Reaction “photo” Convert solar energy to ATP and NADPH
ATP – molecule that stores and releases chemical energy
NADPH – electron carrier, brings electrons and protons around cell to make energy

10. Act One Plot Overview Use the suns energy to: Excite the chlorophyll
Split the water producing Oxygen gas as a waste product
Make energy (ATP & NADPH) the players needed for Act 2

11. Scene Takes place in the thylakoids Membrane stacks in the chloroplast
Contain enzymes to work with light reaction

13. Scene Continued Sunlight strikes the chlorophyll
An electron is lost from chlorophyll
Water is split to replace this lost electron
This daring act of water produces a waste product Oxygen Gas
The electron that left chlorophyll goes to work to make ATP and NADPH

14. The Result of Act One (The Green Area)
ATP and NADPH have been made
Oxygen has been released as a waste product

15. Act Two Calvin Cycle (Light Independent Reaction)
Uses CO2 and Energy to make Sugar
“synthesis”

16. Act II Overall Plot
The energy made in the Light Reaction will add Hydrogen to CO2 to make
C6H12O6 Glucose

17. Act II Takes place in the stroma A cycle
The fluid part of the chloroplast
A cycle
Goes around twice to make one glucose molecule

18. Act II CO2 enters the cycle
It will combine with a 5 carbon molecule - RuBP
This combination causes a rearrangement of carbons to make a molecule that is a sugar

19. Act II (cont.) Six CO2 molecules are needed to make one usable glucose
The carbon atoms not used in making glucose are used to continue the cycle .

20. Calvin Cycle (Blue Portion of Diagram)

21. Plot Details
The next 4 slides provides details of the events of photosynthesis
Use this to follow the steps in the plot
With each slide find the cast member in the diagram

22. Plot Detail 1 CO2 enters the cycle
It will combine with a carbon based molecule
RuBP

23. Plot Detail 2
This combination creates a new molecule
PGA

24. Plot Detail 3 The PGA is rearranged into G3P a sugar
ATP gives the energy
Two G3P will leave to make sugar or starch

25. Plot Detail 4
The remaining G3Ps will rearrange to form RuBP to continue the cycle
ATP gives the energy

26. Act II Summarized The Calvin cycle uses energy from Act I
In the form of ATP & NADPH
No light is needed
The energy is used to turn a 5 carbon molecule + CO2 into glucose
Also to make more of the 5 carbon based molecule necessary for the cycle to continue

27. SO What?
Light energy is used to transfer electrons from H2O to CO2 to make sugar.
In the process Oxygen is released as a waste product
All the Oxygen we breathe has been made this way
Without oxygen, animals, plants, some bacteria any aerobic organism would not be alive.

28. So What Else? Glucose is used to make energy in cellular respiration
Without photosynthesis heterotrophs (humans too) have no source of energy

29. Aerobic
Needs air for the process to occur

30. Heterotroph
Uses another source for food

31. Do Now Questions (Light Dep.)
Name two reactants of the light reactions.
Where in the chloroplast do the light reactions take place?
Name the three products of the light reactions.
Label each product as either energy storage molecule, carrier molecule or waste product.
Why are the energy storage molecule and the carrier molecule important to photosynthesis?

32. Do Now (continued)
The photosystems contain chlorophyll. Where in the chloroplast would you find them?
What is the function of the photosystems?
Is carbon dioxide involved in the light reactions?

33. Sunlight and Water

34. Thylakoid membranes

35. Oxygen waste product
ATP energy molecule
NADPH carrier molecule

36. Needed to go on to dark reactions

37. Pigments collect sunlight for light reactions

38. NO

39. Do Now Questions (Light Indep.)
1. The source of carbon in the light independent reaction is _________.
2. The molecule that transfers high energy electrons between the light-dependent and light-independent reactions is _____.
3. What are the reactants for the light independent reactions?
4. What are the products for the light independent reactions?

40. Do Now Questions
5. What is another name for the light independent reactions?
6. Why is it necessary to keep making RuBP in the cycle?
7. What happens to the ADP and NADP+?
8. What is most of the PGAL used to do in the cycle?

41. Answers
1. CO2

42. 2. NADPH

43. 3. ATP, NADPH, CO2

44. 4. Glucose, (ADP, NADP+)

45. 5. Calvin Cycle

46. 6. Because RuBP is necessary to continue the cycle and make more glucose

47. 7. Go back to light dependent reactions to “charge up”

48. 8. To make RuBP