1. Photosynthesis [8.2] Cell Respiration [8.3] Fermentation [8.3]
Metabolism
Photosynthesis [8.2]
Cell Respiration [8.3]
Fermentation [8.3]

2. Photosynthesis
Most autotrophs create energy from the sun using photosynthesis
The overall equation is:
6CO2 + 6H2O C6H12O6 + 6O2
This occurs in Two Phases:
Light Reaction
The Calvin Cycle
SUNLIGHT

3. 6CO2 + 6H2O C6H12O6 + 6O2 Light-Reaction Phase: Photosystem II
SUNLIGHT
Light-Reaction Phase:
Photosystem II
Uses energy from light to break down H2O
Releases O2
Photosystem I
Harnesses electrons from broken H2O molecules to produces NADPH
Chemiosmosis
Uses H+ ions from broken H2O molecules to harvest the energy to turn ADP into ATP

4. 6CO2 + 6H2O C6H12O6 + 6O2 Calvin Cycle:
SUNLIGHT
Calvin Cycle:
Uses CO2 and the energy stored in NADPH and ATP to produce Glucose (C6H12O6)

5. Alternate Pathways
The environment effects a plant’s ability to perform photosynthesis
Two alternate pathways exist:
C4 plants
CAM plants

6. Cellular Respiration C6H12O6 + 6O2 6CO2 + 6H2O + ATP
Function: to harvest electrons from glucose to produce ATP
Overall Equation:
Three Stages:
Glycolysis
Citric Acid Cycle (CAC) [Kreb’s Cycle]
Electron Transport Chain (ETC)
C6H12O6 + 6O CO2 + 6H2O + ATP

7. Transition to the Citric Acid Cycle
Glycolysis
C6H12O6 + 6O CO2 + 6H2O + ATP
Glycolysis is anaerobic, meaning that it does not require oxygen.
Glucose is broken down yielding:
Energy (ADP -> ATP)
Electron carriers (NADH)
Pyruvate
Transition to the Citric Acid Cycle
C6H12O6 + 6O CO2 + 6H2O + ATP
Requires oxygen (Aerobic)
Pyruvate converted to Acetyl CoA

8. Citric Acid (Kreb’s) Cycle
C6H12O6 + 6O CO2 + 6H2O + ATP
Step 1- Acetyl CoA Citric Acid
Step 2- Citric Acid broken down:
Energy (ADP -> ATP)
Electron carriers: NADH & FADH2
Waste CO2
Step 3- Acetyl CoA and Citric Acid are regenerated to repeat the cycle.

9. Electron Transport Chain
C6H12O6 + 6O CO2 + 6H2O + ATP
A flow of electrons from electron carriers NADH & FADH2 are used to harness energy
ETC is Aerobic
Final electron acceptor is Oxygen
H+ + O2 = H2O
Net 36 ATP in Eukaryotes, 38 ATP in Prokaryotes

10. Anaerobic Respiration
What happens when there is NO oxygen?
Glycolysis can still occur
Kreb’s cycle and electron transport cannot
Instead, pyruvate goes into the anaerobic process known as fermentation
Occurs entirely in the cytoplasm and regenerates NAD+

11. Fermentation Two Types: Lactic Acid Fermentation-
Pyruvate is converted into lactic acid
In muscle cells, occurs when body cannot supply enough oxygen
In microorganisms this occurs to make cheeses, yogurts, and sour cream.

12. Fermentation Two Types: Alcohol Fermentation
Occurs in yeast and some bacteria
Converts pyruvate into CO2 and ethanol
NAD+ is regenerated