1. Photosynthesis

2. Light Absorption Sun gives off visible light (ROYGBIV)
Unabsorbed light reflects to our eyes
Most green light not absorbed by leaves
Chlorophyll absorbs sunlight
Absorb mostly reds and blues

3. Prism
White light

4. Which color(s) are being reflected
Which color(s) are being reflected? Yellow Which color(s) are being absorbed? Red, Orange, Green, Blue, Indigo, Violet

5. Which color(s) are being reflected
Which color(s) are being reflected? Blue Which color(s) are being absorbed? Red, Orange, Yellow, Green, Indigo, Violet

6. Which color(s) are being reflected
Which color(s) are being reflected? None…Black is the absence of light Which color(s) are being absorbed? All….ROYGBIV

7. Which color(s) are being reflected
Which color(s) are being reflected? All…ROYGBIV Which color(s) are being absorbed? None

8. Which color(s) are being reflected
Which color(s) are being reflected? Green Which color(s) are being absorbed? Red, Orange, Yellow, Blue, Indigo, Violet

9. The Chloroplast Site of photosynthesis
Thylakoid membranes: light dependent reactions
Stroma (fluid interior): light independent reactions

10. Stomata: pore underneath leaves through which gases enter/exit

11. Photosynthesis Overview
Two Stages
1) Light Dependent Reactions
Photosystems: groups of molecules that capture/transfer energy
Creates: O2, ATP, NADPH
2) Light Independent Reactions
Creates: Glucose

12. Light Dependent Reactions: Photosystem II
Step 1:
Chlorophyll absorbs sunlight
Chlorophyll e- become excited & transfer to thylakoid membrane
Thylakoid membrane becomes negatively charged
Starts an electron transport chain

13. H2O broken into H+, e-, and O
Step 2 & 3:
H2O broken into H+, e-, and O
e- replace those lost by chlorophyll
O waste
H+ pumped inside the thylakoids and accumulate

14. Thylakoid membrane
Thylakoid membrane becomes negatively charged e e e e e e e e e
chlorophyll
chlorophyll e e H e
Electrons replace those which left chlorophyll H e e H O e H H H
Oxygen waste is released O O

15. The process keeps repeating
The plants takes in water H H H H e e e e e e
Thylakoid membrane
Thylakoid membrane becomes negatively charged e e e e e e e e e e e e e e e e e e
chlorophyll
chlorophyll e e H e
Electrons replace those which left chlorophyll H e e H O e H H H
Oxygen waste is released O O

16. Light Dependent Reactions: Photosystem I
Chlorophyll absorbs sunlight
Chlorophyll e- become excited & transfer to thylakoid membrane
Accumulate with those from photosystem II e- e- e- e- e-

17. NADPH produced (H taxi)
e- causes H+ to bond with NADP
NADPH will be used later
ATP produced
H+ ions diffuse and bond ADP with Pi
ATP will be used later H+ H+ H+ e- e- e- e- e- e- e- e- e- e- e-
ATP
ATP
ATP

18. Light Dependent Summary
O2, ATP, NADPH created
NO GLUCOSE CREATED!

19. Light Independent Reactions (Calvin Cycle)
Step 1: CO2 bonds with RuBP (5C) molecule to make a 6C molecule

20. RuBP 6C molecule CO2 bonds with RuBP C C
Six carbon molecule is created
CO2

21. Step 2: 6C molecule splits into two PGAL molecules (3C)
ATP & NADPH provide the energy

22. NADPH
NADPH
NADPH
NADPH
NADPH
NADPH
NADPH (from light dependent cycle) drops off H
ATP (from light dependent cycle) provides energy to break the molecule into PGAL
ATP
6C molecule
ADP H H H
ADP
ADP
ADP
ATP
ADP
ADP
ATP C C C C C C C C
ATP
ATP H H H
ATP
PGAL
PGAL

23. Step 3:
Some PGAL (3C) bonds to make glucose (6C)
Some PGAL recycled to start the cycle over

24. PGAL
PGAL
PGAL
PGAL
glucose! C C
PGAL
PGAL C C C C C C C C C C
PGAL
glucose!
PGAL bonds with PGAL….to make glucose!
Glucose is used by plant cell mitochondria to create ATP in the process of cellular respiration
PGAL is used to restart the Calvin Cycle

25. Step 4:
PGAL (3C) bonds to remake a RuBP (5C) molecule with help of ATP
CO2 bonds with RuBP (5C) to restart the cycle

26. C C C C C C C C C C C C C C C
ATP
ATP
ATP
PGAL broken apart by ATP

27. 6C molecule 6C molecule 6C molecule RuBP C C C C C C C C C C C C C C C
CO2 C C C C
6C molecule C C C C C C C C
CO2
RuBP C
CO2
Unstable C atoms recombine to make RuBP (5C) molecules
RuBP molecules bond with CO2 again

29. Light Independent Summary
CO2, ATP, & NADPH create glucose

30. Your essay question on the next test!
Trace the flow of energy, including ATP, from the sun to your muscles, after eating a green leaf salad.

31. Kobe Kuiz Place these steps in order from start to finish:
A) Electron transport chain creates NADPH and ATP energy
B) 3C molecule broken by ATP into 5C molecule
C) PGAL created when 6C molecule broken down
D) Water broken into H+, e-, and O components
E) Sunlight causes chlorophyll electrons to flow into thylakoid membrane
F) 3C molecule bonds to create glucose
G) CO2 bonds with RuBP

32. Kobe Kuiz Place these steps in order from start to finish:
E) Sunlight causes chlorophyll electrons to flow into thylakoid membrane
D) Water broken into H+, e-, and O components
A) Electron transport chain creates NADPH and ATP energy
G) CO2 bonds with RuBP
C) PGAL created when 6C molecule broken down
F) 3C molecule bonds to create glucose
B) 3C molecule broken by ATP into 5C molecule