1. Photosynthesis Short Answer Practice

2. #1 What makes chlorophyll so unique?
Made of photon-absorbing porphyrin ring
with Mg in center
Nitrogen atoms around
the Mg
Photon of light
resonates the e-
between the single
and double bonds

3. #1 What makes chlorophyll so unique?
Hydrocarbon tail
Attaches to
Integral protein in the
Thylakoid disk
membrane

4. #2 Compare PSII and PSI Both absorb photons and excite e-
Both contain chlor a + other pigments
Reaction center of PSII absorbs 680 nm
Reaction center of PS I absorbs 700 nm
PSII receives e- from split water
PS I receives e- from Pc (end of ETC)

5. #2 Compare PSII and PSI PSII PSI -PSII gives electrons to ETC
-PSI give electrons to NADP+
PSII PSI
FOUND IN THYLAKOID DISK MEMBRANE

6. #3Compare chemiosmosis and ETC in mitochondrion and chloroplast:
e- come from food molecules
e- have high potential energy in bonds in organic compounds
e- passed to oxygen
Oxygen pick up H+ to form H2O
Chloroplast
e- come from splitting of H2O
Light energy excites e- to a higher energy level
e- flow from H2O to reaction center 680 in PSII to reaction center 700 in PSI
From PSI to NDR to reduce NADP+ to NADPH

7. #4 CFC’s Chlorofluorocarbons Were put in aerosols, refrigerants,
and styrofoam
Products containing CFC’s were Banned by those signing the Montreal Protocol 1987
Recovery of ozone not expected until 2060’s.

8. Ozone O3 O3 (seen in teal blue in diagram)
Protective layer around the earth keeping harmful UV rays from reaching the earth
UV rays
(some enter, some
blocked)
Infrared (trapped)

9. #4 CFC’s
Cl breaks off an oxygen from ozone (O3) so it is no longer a protective layer around the earth.

10. Global Warming
refers to the rising average temperature of Earth's atmosphere and oceans

11. Greenhouse Gases
CO2 (carbon dioxide) – most important! H2O (water vapor) CH4 (methane) CFC’s (chlorofluorocarbons) These can absorb heat and warm the atmosphere.

12. Causes and Effects of Global Warming
Increase in greenhouse gases: especially CO2 (mostly from fossil fuel emissions)
-Kills coral reefs
-Melts polar icecaps
-Raises ocean levels
-Upsets weather

13. CFC’s and Global Warming

14. #4 Global Warming Solutions
Photosynthesis removes CO2
from the atmosphere
Reduce fossil fuel use (CO2 is an important global warming gas -absorbs heat)
Use alternate energy sources (wind, solar, geothermal, hydroelectric)