Nitrogen gas returns to the atmosphere by the action of

1. Nitrogen gas returns to the atmosphere by the action of  • nitrogen fixing bacteria. • denitrifying bacteria. • nitrifying bacteria. • nitrate fertilizers. 15

2. The sequence of energy flow through a food chain is  • primary consumers‑ producers‑ higher order consumers. • producers‑ higher order consumers‑ primary consumers. • higher order consumers‑ primary consumers‑ producers. • producers‑ primary consumers‑ higher order consumers.  15

3. In a terrestrial ecosystem, the trophic level that would contain the largest biomass would be the • producers. • primary consumers. • secondary consumers. • highest order consumers. • decomposers.  15

4. The study of how living things interact is called: • Ecosystems • Abiotic factors • Ecology • The Energy Pyramid 10

5. The source of energy for almost all life on Earth is: • Fungi • Animals • Water • Sunlight 15

6. In an energy pyramid, the bottom level represents: • Consumers • Producers • Scavengers • Decomposers 15

7. An example of a consumer in a pond ecosystem is: • Water lily • Algae • Reed • Frog 15

8. Which of these food chains is in the correct order? • caterpillar, cattail, frog, water snake • cattail, caterpillar, frog, water snake • water snake, frog, caterpillar, cattail • cattail, frog, caterpillar, water snake 15

9. In an energy pyramid, the lowest level has: • less energy than the top level • less energy than the second level • more energy than the top level • the same amount of energy as the second level 15

10. A food chains shows: • one possible pathway for energy • many possible pathways for energy • the amount of energy available to a producer • the amount of energy available to a consumer 15

11. Decomposers are important to ecosystems because they: • are at the highest level of the energy pyramid • change simple compounds into more complex ones • make nutrients available for producers to reuse • convert light energy into sugars through photosynthesis 15

12. Two examples of decomposers are: • fungi and bacteria • algae and marine mammals • carnivores and herbivores • ferns and mosses 15

13. A caterpillar eats a leaf, and a bird eats the caterpillar. In this interaction, the bird is a: • Producer • Herbivore • Primary consumer • Secondary consumer 15

14. How is a food web model different from a food chain? • In a web, energy moves from an organism to only one other. • In a web, energy may move to many organisms from one. • In a web, an organism gets energy from one source. • In a web, an organism receives less energy than in a chain. 15

15. An unusually cold winter causes the squirrel population to decrease. This is an example of temperature as a: • Carrying capacity • Limiting factor • Climax community • Pattern in space 15

16. An animal that eats only plants is a: • Primary consumer • Secondary consumer • Tertiary consumer • Primary producer 15

17. A snake that eats an insect-eating frog is a: • Primary consumer • Secondary consumer • Tertiary consumer • Primary producer 15

18. Which of the following is difference between the nitrogen and carbon cycles? • Nitrogen can exist as a solid but carbon cannot. • Carbon is released through decomposition but nitrogen is not. • Carbon is released through respiration but nitrogen is not. • Carbon is cycled through animals but nitrogen is not. 15

19. Which of the following makes the nitrogen cycle unique? • It is the only nutrient cycle without a gas • Nitrogen is always only a liquid • Nitrogen is found in plants, animals and the soil • Nitrogen requires specific bacteria for its cycle 15

20. Which of the following correctly traces the path of a raindrop through the water cycle? • precipitation, run-off, evaporation, condensation • precipitation, condensation, run-off, evaporation • precipitation, evaporation, run-off, condensation • precipitation, evaporation, condensation, run-off 15

21. Which of the following isa way carbon is added to the atmosphere? • Evaporation of water • Forest fires • Photosynthesis • Formation of fossil fuels 15

22. Why are legumes such as peas and alfalfa considered good for soil? • They add valuable humus to the soil when they die and decay. • They absorb water and help control runoff. • Their leaves are able to photosynthesis at a very high rate. • They have nitrogen fixing bacteria in their roots. 15

23. Where is the oxygen we breathe produced? • in the rocks • by decaying organisms • during photosynthesis • as water evaporates 15

24. What is the major factor that limits the number and types of plants that can grow in Utah? • the amount of rainfall we receive • the number of people living Utah • the types of animals found in Utah • the location of Utah on the continent 15

25. Which of the following is a way carbon dioxide can be removed from the air? • building dams • fertilizing crops • mining coal • planting trees 15