1. The animation for multiple choice questions may not work on some computers.

2. TRUE or FALSE? During photosynthesis, plants convert atmospheric carbon into proteins.

3. TRUE or FALSE? Ecosystem pollution can result from both natural events and human actions.

4. Which of the follow are reactants in a photosynthesis reaction? None of the above Oxygen and water Carbon dioxide and water Oxygen and glucose Carbon dioxide and glucose

5. Which of the following types of biological molecules include the “blueprint” for life? Phospholipids Lipids Carbohydrates Amino acids Nucleic acids

6. What process directly converts atmospheric nitrogen, N 2, into a form plants can use? Sedimentation Eutrophication Nitrification Denitrification Nitrogen fixation

7. A pollutant with which of the following characteristics would most likely bioaccumulate in a primary consumer? None of the above fatal in very low concentrations easily broken down in the body not taken up by plants degrades slowly in the environment

8. What is one way that human agriculture affects ecosystems? None of the above enhancement of natural stream flow patterns increased growth of trees decreased production of pollutants depletion of soil nutrients

9. Organisms that are low in marine food chains, such as plankton and shrimp, generally contain very low levels of mercury. Organisms that are higher in the food chains, such as tuna fish and sharks, generally have much higher levels of mercury in their bodies. Which of the following processes best explains this observation? succession pollutant cycling biodegradation natural selection biomagnification

10. Which of the following processes reduces the availability of phosphorus for living things? decomposition of dead organisms agricultural runoff weathering of rock production of fertilizer burial of marine skeletons

11. Which of the following processes removes carbon from the atmosphere? Cellular respiration in muscle cells Decomposition of dead organisms Burning fossil fuels Cutting down trees Photosynthesis in ocean plankton

12. Which of the following elements is required for the formation of nucleic acids and proteins, but not sugars? None of the above Hydrogen Oxygen Carbon Nitrogen

13. Which of the following is an inorganic compound that is part of the nitrogen cycle? None of the above methane glucose water ammonia

14. How do consumers get the nitrogen their bodies need? consumers do not nitrogen through the uptake of nitrogen-containing fertilizers through symbiosis with nitrogen-fixing bacteria by breathing the nitrogen in the air by eating other organisms

15. Living organisms need ____________ because it makes up part of the backbone of DNA molecules and is an important part of cell membranes. molybdenum sulfur oxygen nitrogen phosphorus

16. Which of the following elements is found in all biological molecules? plutonium sulfur nitrogen phosphorus carbon

17. Which of the following processes best explains why an adult fish has a DDT concentration of 2.07 ppm while an osprey has a DDT concentration of 13.80 ppm? None of the above bioaccumulation biodegradation bioremediation biomagnification

18. How is the phosphate made available to plants and animals on Earth? None of the above Lightning converts phosphorus into phosphate. Bacteria convert phosphorus into phosphate. Plants release phosphorus during photosynthesis. Weathering releases phosphate into the soil.

19. A farmer decides to grow peas and soybeans. He plants these two crops in all of his fields. What impact would this have on the nutrients in the soil? None of the above There would be a decrease in the amount of nitrate (NO 3 − ). There would be an increase in the amount of phosphate (PO 4 3− ). There would be an increase in the amount of carbon dioxide (CO 2 ) There would be an increase in the amount of ammonium (NH 4 + ).

20. Which organism in the picture on the left would have the highest concentration of PCBs? The Killer Whale

21. What do the following processes have in common? - Volcanic Activity - Decomposition - Cellular Respiration None of the above They are all part of the nitrogen cycle. They increase the PO 4 in the soil. They help reduce greenhouse gases. They all release CO 2 into the atmosphere.

22. Your classmate tells you that all forest fires are bad. Which of the following observations could you use to challenge your classmate’s assumption? None of the above. Forest fires threaten human settlements. Forest fires release carbon dioxide into the environment. Forest fires destroy bird nests and animal habitats. Forest fires recycle nutrients and create more diversity in the forest.