1. C HECK & R EFLECT Page 190, #s 1-11

2. W HAT ROLE DO DECOMPOSERS PLAY IN THE NITROGEN CYCLE ? Decomposers break down large nitrogen- containing molecules from dead organisms and animal waste into nitrogen that can be used to form useful compounds.

3. W HAT IS POLLUTION ? G IVE 3 EXAMPLES OF CHEMICAL POLLUTION. Pollution is any change in the environment that produces a condition that is harmful to living things. Examples include sulfur dioxide, nitrogen oxides, mercury, lead, etc.

4. W HAT DO THE NUMBERS ON THE FERTILIZER LABEL IN F IGURE 1.9 INDICATE ? 4-6-8 First number is percentage of nitrogen compounds present (4%), second number is percentage of phosphorus compounds present (6%), third number is percentage of potassium compounds present (8%).

5. D EFINE THE TERM “ HERBICIDE ” A herbicide is a chemical used to kill or control weeds or other plants.

6. H OW DO SANITARY LANDFILL SITES PREVENT CHEMICALS FROM MOVING INTO THE GROUNDWATER ? Plastic liners and compacted clay are used to prevent solutions from entering groundwater.

7. D ESCRIBE 2 WAYS THAT NITROGEN IS REMOVED FROM AN ECOSYSTEM. Nitrogen compounds are taken up by plants and removed when the plants are harvested. Nitrogen compounds can be carried away from an ecosystem because they are water soluble (can be dissolved in water). They can be changed by bacteria into nitrogen gas that returns to the atmosphere and can’t be used by plants.

8. W HAT POLLUTANTS ARE RELEASED FROM FOSSIL FUEL COMBUSTION ? Fossil fuel combustion releases nitrogen and sulfur compounds as well as carbon dioxide. Lead and mercury are also released.

9. W HY DO FARMERS USE FERTILIZER ? Fertilizers are used to supply nutrients to a nutrient-deficient soil so plants grow better. Fertilizers increase crop yield (leads to higher production and more $$).

10. W HY DOES SEWAGE NEED TO BE TREATED ? Sewage has to be treated to remove substances that can have a harmful impact on living things in the environment.

11. S UGGEST 2 WAYS THAT YOU COULD REDUCE YOUR NEED FOR A FUEL - BURNING VEHICLE. Answers vary, but can include riding the bus, car-pooling, riding a bicycle, and walking more. Living close to work/school/etc. “High density” communities, as opposed to “suburban sprawl”.

12. I DENTIFY 2 ISSUES RELATED TO HUMAN ACTIVITIES THAT CHANGE CHEMICALS IN THE ENVIRONMENT. E XPLAIN WHY EACH IS AN ISSUE. Answers vary, but one issue might be sulfur dioxide emissions- remember from the video in China how the air can be so thick with pollution it can be seen and smelled/tasted; cause many health problems, including respiratory problems. “Sulfur dioxide emissions should be reduced” could be an issue because some people would agree with it (environmental views) and some people would disagree with it (economic views). Issue: an important topic or problem for debate or discussion.