1. Compare the light absorption of chlorophyll A and chlorophyll B.
Bell Ringer (1)
Compare the light absorption of chlorophyll A and chlorophyll B.
Hint: Use the graph on pg. 207
Then read pg. 209!

2. Photosynthesis Reactions
Unit 4: Energize Your Life

3. Plants Autotrophs – produce their own food (glucose)
Process called photosynthesis
Mainly occurs in the leaves:
a. stoma - pores
b. mesophyll cells
Mesophyll
Cell
Chloroplast
Stoma 3

4. 2 Parts of Photosynthesis
Light-Dependent Reactions
Requires light
Occurs in the thylakoids
Light-Independent Reactions
(a.k.a. Dark Reaction or Calvin Cycle)
Does NOT require light
Occurs in the stroma

5. Light-Dependent Big Idea
Light is absorbed by chlorophyll to split water molecules and give off oxygen.
This “charges up” the energy molecules ATP and NADPH.
Photosystem II  ETC (Chemiosmosis) Photosystem I

6. Noncyclic Electron Flow
P700
Photosystem I
P680
Photosystem II
Primary
Electron
Acceptor
ETC
Enzyme
Reaction
H2O
1/2O2 + 2H+
ATP
NADPH
Photon
2e-
SUN
H2O is split in PSII & ATP is made, while the energy carrier NADPH is made in PSI 6

7. Chemiosmosis ADP + P ATP PS II PS I E T C Thylakoid Space
H+ H+
ATP Synthase
high H+
concentration H+
ADP + P
ATP
PS II
PS I E T C
low H+
Thylakoid
Space
SUN
(Proton Pumping) 7

8. Light-Independent (Calvin Cycle) Big Idea
Energy is used from ATP and NADPH.
The “left-over” hydrogens from the water are carried to the stroma by NADPH.
They are combined with CO2 to make glucose.
(Carbon Fixation)

9. Calvin Cycle (C3 fixation)
6CO2
6C-C-C-C-C-C
6C-C-C
6C-C-C-C-C
12PGA
RuBP
12G3P
(unstable)
6NADPH
6ATP
C-C-C-C-C-C
Glucose
(6C)
(36C)
(30C) C3
glucose 9

10. Light-Dependent Light-Independent Reaction Reaction (Calvin Cycle)
Energy Source = ATP and NADPH
Occurs in the Stroma
Changes ATP into ADP
Changes NADPH into NADP
Uses CO2 & “left-over” H from NADPH
Produces Glucose
Energy Source= Light
Occurs in the Thylakoids
Changes ADP into ATP
Changes NADP into NADPH
Uses H2O
Produces Oxygen Gas

11. Energy for Life on Earth
Sunlight is the ULTIMATE energy for all life on Earth
Plants store energy in the chemical bonds of sugars
Chemical energy is released as ATP during cellular respiration 11

12. How Do We Get Energy From ATP?
By breaking the high- energy bonds between the last two phosphates in ATP
Copyright Cmassengale 12

13. What is the Process Called?
HYDROLYSIS (Adding H2O)
H2O
Copyright Cmassengale 13

14. Copyright Cmassengale
How is ATP Re-Made?
The reverse of the previous process occurs.
Another Enzyme is used!
ATP Synthase
Copyright Cmassengale 14

15. Overall Equation for Cellular Respiration
C6H12O O2
YIELDS
6CO2 + 6H20 + e ATP’s
Copyright Cmassengale 15

16. Other Cellular Respiration Facts
Metabolic Pathway that breaks down carbohydrates
Process is Exergonic as High-energy Glucose is broken into CO2 and H2O
Process is also Catabolic because larger Glucose breaks into smaller molecules
Copyright Cmassengale 16

17. Where Does Cellular Respiration Take Place?
It actually takes place in two parts of the cell:
Glycolysis occurs in the Cytoplasm
Krebs Cycle & ETC Take place in the Mitochondria
Copyright Cmassengale 17

18. Copyright Cmassengale
Glycolysis Summary
Takes place in the Cytoplasm
Anaerobic (Doesn’t Use Oxygen)
Requires input of 2 ATP
Glucose split into two molecules of Pyruvate or Pyruvic Acid
Also produces 2 NADH and 4 ATP
Pyruvate is oxidized to Acetyl CoA and CO2 is removed
Copyright Cmassengale 18

19. Copyright Cmassengale
Fermentation
Occurs when O2 NOT present (anaerobic)
Called Lactic Acid fermentation in muscle cells (makes muscles tired)
Produces Lactic Acid and NAD+
Called Alcoholic fermentation in yeast
Produces Ethyl Alcohol, CO2, and NAD+
0 additional ATP are produced after Glycolysis
Copyright Cmassengale 19

20. Copyright Cmassengale
Krebs Cycle
ATP
NETS: 3NADH, 1ATP, 1FADH2, & 2CO2
Copyright Cmassengale 20

21. Electron Transport Chain Summary
34 ATP Produced
H2O Produced
Occurs Across Inner Mitochondrial membrane
Uses coenzymes NAD+ and FAD+ to accept e- from glucose
NADH = 3 ATP’s
FADH2 = 2 ATP’s
Copyright Cmassengale 21

22. Electron Transport Chain Animation
Copyright Cmassengale 22