1. 4.2/4.3 Intro to Photosynthesis
Set up Cornell Notes on pg. 43
Topic: 4.2/4.3 Intro to Photosynthesis
Essential Question:
What are the role of chloroplasts and chlorophyll in photosynthesis?
Don’t forget to add it to your T.O.Contents!
4.2/4.3 Intro to Photosynthesis
2.1 Atoms, Ions, and Molecules
What are the role of chloroplasts and chlorophyll in photosynthesis?
Key Concept: The overall process of photosynthesis produces sugars that store chemical energy

2. How does ADP become ATP again?
SPONGE
How does ATP become ADP?
Which has more energy?
How does ADP become ATP again?

3. ATP has more energy ADP has less energy
ATP becomes ADP when a phosphate group is removed and energy is released.
ATP has more energy ADP has less energy
ADP can be converted back into ATP by the addition of a phosphate group.
phosphate removed

4. CA Standard
The fundamental life processes of plants and animals depend on a variety of chemical reactions that occur in specialized areas of the organism’s cells.
1.F Know usable energy is captured from sunlight by chloroplasts and is stored through the synthesis of sugar from carbon dioxide.

5. Table Talk
Imagine you just planted beautiful roses in your garden. What materials are crucial to the roses survival? In other words, what do the roses need to stay alive?

6. Water (H20) Sunlight Carbon Dioxide (CO2) Soil
What materials are crucial to the roses survival? In other words, what do the roses need to stay alive?

7. KEY CONCEPT The overall process of photosynthesis produces sugars that store chemical energy.

8. List a few things that use energy from sunlight.

9. Solar powered homes, cars, and calculators are just a few things that use energy from sunlight.
In a way you are solar powered. Although the sun does not directly give you the energy.

10. How do we get our chemical energy?

11. How do we get our chemical energy?
Plants from the sun
Animals from plants or other animals that fed on plants

12. Photosynthesis is a process that captures energy from sunlight to make sugars that store chemical energy. Therefore, directly or indirectly, the energy for almost all organisms begins as sunlight.
(Sugar)

13. Photosynthetic organisms are producers.
Producers make their own source of chemical energy (they make their own food).
Ex: Plants

14. Chlorophyll is a molecule that absorbs light energy.
chloroplast
leaf cell
leaf
In plants, chlorophyll is found in organelles called chloroplasts.
Photosynthesis occurs here.

15. What are the roles of chloroplasts and chlorophyll in photosynthesis?
Photosynthesis occurs in chloroplasts.
Chlorophyll is a light-absorbing molecule located in chloroplasts.

16. Photosynthesis takes place in two parts of chloroplasts.
thylakoid
Coin-shaped compartments that contain chlorophyll
grana- stacks of thylakoids
Stroma
Fluid that surrounds the grana
chloroplast
stroma
grana
Thylakoid

17. Where does photosynthesis take place?
Sponge
Where does photosynthesis take place?
What is the function of chlorophyll?
List the 2 products of photosynthesis.

18. Where does photosynthesis take place? Chloroplasts
Sponge
Where does photosynthesis take place?
Chloroplasts
2. What is the function of chlorophyll?
To absorb the energy from the sunlight
List the 2 products of photosynthesis.
Oxygen (O2)
Sugar

19. The equation for photosynthesis is: 6CO2 + 6H2O  C6H12O6 + 6O2
Carbon dioxide water light, enzymes a sugar oxygen
C6H12O6
granum (stack of thylakoids)
thylakoid
sunlight
1 six-carbon sugar
6H2O
6CO2
6O2
chloroplast 1 2 4 3
energy
stroma (fluid outside the thylakoids)

20. Light-dependent reactions capture energy from sunlight (The reactions depend on light!).

21. Light DEpendent Light INdependent 1 2 4 3 granum (stack of thylakoids)
C6H12O6
granum (stack of thylakoids)
thylakoid
sunlight
1 six-carbon sugar
6H2O
6CO2
6O2
chloroplast 1 2 4 3
energy
stroma (fluid outside the thylakoids)
Light DEpendent
Light INdependent

22. 6 O2 (oxygen) are released as waste
Light Dependent reactions- take place in the thylakoids
Sunlight is absorbed by chlorophyll
The energy is carried by ATP and NADPH molecules
6 H2O (water) molecules are broken down
6 O2 (oxygen) are released as waste

24. The first stage of photosynthesis captures and transfers energy.
The light-dependent reactions include groups of molecules called photosystems.
Photosystems are molecules that capture and transfer energy in the thylakoids.

25. Photosystem II captures and transfers energy.
chlorophyll absorbs energy from sunlight
energized electrons enter electron transport chain- which is a series of proteins in the membrane of the thylakoid
water molecules are split
H+ ions
Electrons
Oxygen
Oxygen is released as waste

26. Photosystem II captures and transfers energy.
hydrogen ions are transported across thylakoid membrane

28. Photosystem I captures energy and produces energy-carrying molecules.
The electrons from photosystem II move on to photosystem I
chlorophyll absorbs energy from sunlight (even more high-energy electrons)
The electrons are added to NADP+ (similar to ADP) which are used to make NADPH (enzyme like ATP)
NADPH is transferred to light-independent reactions

29. Photosystem I captures energy and produces energy-carrying molecules.
Hydrogen ions diffuse through the thylakoid membrane
ATP is produced

32. The light-dependent reactions produce ATP.
hydrogen ions flow through a channel in the thylakoid membrane
ATP synthase attached to the channel makes ATP
The energy from both ATP and NADPH is used to make sugars during light-independent reactions.

33. The light-independent reactions use energy from light-dependent reactions to make sugars.
takes place in the stroma
needs 6 CO2 (Carbon Dioxide) from atmosphere
uses light-Dependent ATP/NADPH (energy) to build a sugar molecule which stores some of the energy that was captured from sunlight

34. Calvin Cycle

35. The second stage of photosynthesis uses energy from the first stage to make sugars.
Light-independent reactions occur in the stroma and use CO2 molecules.

36. 1. carbon dioxide molecules enter the Calvin cycle
Calvin Cycle: uses carbon dioxide CO2 gas from the atmosphere and the energy carried by ATP and NADPH to make simple sugars.
1. carbon dioxide molecules enter the Calvin cycle
2. energy is added and carbon molecules are rearranged
3. a high-energy three-carbon molecule leaves the cycle 2. 3.
Split into 2, 3-carbon molecules 1.

37. 4. two three-carbon molecules bond to form a sugar
5. remaining molecules stay in the cycle
6. 3-carbon molecules are changed back into 5-carbon molecules using ATP 4. 5. 6.

38. 2. 4. 3. 1.
sugar 5. 6.

40. What are the reactants and products of photosynthesis?
Sponge #5
What are the reactants and products of photosynthesis?

41. Reactants: (What do we need for photosynthesis?
Sunlight
H2O water
CO2 carbon dioxide
Products:
O2 oxygen
Glucose (sugar)
The equation for photosynthesis is:
6CO H2O 
C6H12O O2

42. Light dependent reactions
Sunlight + H  O2 reactions in thylakoids CO  1 six-carbon sugar Calvin cycle
ATP NADPH
Light independent reactions

43. What are light-dependent reactions? Name their product.
SPONGE 4
What are light-dependent reactions? Name their product.
What are light-independent reactions? Name their product.

44. Light-dependent reactions capture energy from sunlight and produces oxygen as a byproduct.
Light-independent reactions use energy from the light-dependent reactions to make sugars.
ATP NADPH