1. Hard Facts
What do you need to memorize in order to get a 5 on the AP Environmental Science Exam?

2. Photosynthesis
6 CO H2O + radiant energy
C6H12O6 + 6 H2O + 6 O2

3. Cellular Respiration
C6H12O6 + 6 O2 + 6 H2O
6 CO H2O + energy

4. Photochemical Smog Net Reaction: NO + VOCs+ O2 + UV  O3 + PANs
Nitric oxide
Nitric oxide
Volatile organic compounds
e.i. benzene, acetone, formaldehyde
Volatile organic compounds
e.i. benzene, acetone, formaldehyde
Tropospheric ozone
Tropospheric ozone
Peroxyacyl Nitrates
CH3COOONO2
Peroxyacyl Nitrates
CH3COOONO2
Photochemical smog is a mixture of air pollutants formed by the reaction of nitrogen oxides and volatile organic hydrocarbons under the influence of sunlight.

5. Stratospheric Ozone Depletion

6. Sun UV radiation Cl C F Cl Cl O Cl Cl O O O Cl O O Stepped Art
Ultraviolet light hits a chlorofluorocarbon (CFC) molecule, such as CFCl3, breaking off a chlorine atom and leaving CFCl2.
Once free, the chlorine atom is off to attack another ozone molecule
and begin the cycle again.
UV radiation Cl C F Cl Cl O Cl
A free oxygen atom pulls
the oxygen atom off
the chlorine monoxide
molecule to form O2.
The chlorine atom attacks an ozone (O3) molecule, pulling an oxygen atom off it and leaving an oxygen
molecule (O2). Cl O O O Cl O
The chlorine atom and
the oxygen atom join to
form a chlorine monoxide
molecule (ClO). O
Stepped Art
Fig , p. 486

7. The Greenhouse Effect

9. Biogeochemical Cycles

10. Cycling of Materials within Ecosystems
Carbon cycle: 10

11. Cycling of Materials within Ecosystems
Nitrogen cycle:
Atmospheric nitrogen (N2)
Nitrogen fixation by humans
Biological nitrogen fixation
NH3 & NH4-
Decomposition
Denitrification
Plant & animal proteins
Internal cycling
Assimilation
Nitrification
NO3- 11

12. Cycling of Materials within Ecosystems
Phosphorus cycle:
Phosphate mining
Phosphate rocks
Fertilizer containing phosphates
Animals, crops
Erosion
Excretion / decomposition
Internal cycling
Dissolved phosphates
Internal cycling
Soil phosphates
Marine organisms
Marine sediments
Erosion 12

13. Cycling of Materials within Ecosystems
Sulfur cycle: 13

14. Eutrophication