Biology HS/Science Unit: 02 Lesson: 02
Nitrogen and Carbon Cycles Web Quest KEY Objective: To determine the importance of the nitrogen and carbon cycles and how these cycles function on Earth. Nitrogen Cycle Using a reliable search engine, find appropriate websites to read and learn about the nitrogen cycle. Be sure and use any websites suggested by your teacher. Then, answer the questions below. Questions: 1. Why is nitrogen important to organisms? Student answers will vary, but should include most of the following concepts: Organisms use nitrogen to carry out life functions. Nitrogen is an important component of DNA, RNA, proteins, and chlorophyll. 2. What must happen to nitrogen before plants and animals can use it? Nitrogen must be converted, or “fixed”, into forms that are useable by plants (ammonium or nitrate ions). Then, animals eat the plants and assimilate the nitrogen from the plants. 3. What organisms are able to “fix”, or convert, nitrogen to be usable by plants? How else might nitrogen be “fixed” or converted? Symbiotic and free-living bacteria are able to fix nitrogen to be usable by plants. Nitrogen can also be fixed by lightning strikes, fires, or through industrial methods. However, it is mostly done by bacteria. 4. Draw and label a graphic showing your understanding of the nitrogen cycle. Student graphics will vary, but should include the following concepts: nitrogen in the atmosphere, nitrogen in decaying matter and waste, nitrogen assimilating to animals, nitrogen fixation by bacteria, decomposition by bacteria and fungi, denitrification, and nitrification.
Information References: Unknown. (n.d.). The nitrogen cycle. Retrieved from http://www.kidsgeo.com/geography-forkids/0161-the-nitrogen-cycle.php Gardiner, L. (May, 2007 07). The nitrogen cycle. Retrieved from http://www.windows2universe.org/earth/Life/nitrogen_cycle.html ©2012, TESCCC
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Biology HS/Science Unit: 02 Lesson: 02
Unknown. (n.d.). The nitrogen cycle. Retrieved from http://www.teachersdomain.org/asset/lsps07_int_nitrogen/ Unknown. (Nov, 2010 08). The nitrogen cycle. Retrieved from http://www.to14.com/game.php? id=4d486a36be2dd Unknown. (n.d.). Nitrogen cycle. Retrieved from https://files.nyu.edu/pet205/public/nitrogen.html
Carbon Cycle Using a reliable search engine, find appropriate websites to read and learn about the carbon cycle. Be sure to use any websites suggested by your teacher. Then, answer the questions below. Questions: 1. How is carbon extracted from the atmosphere? Carbon is extracted from the atmosphere through plants in a process called photosynthesis. 2. How do animals and humans get carbon? Animals and humans get carbon through eating plants or eating animals that eat plants. 3. What happens to the carbon in plants and animals when they die? They decay, and the carbon is released back into the ground. Some of the carbon gets buried far underground and will become fossil fuels after many millions of years. 4. What are ways in which carbon is released into the atmosphere? Carbon can be released into the atmosphere by animal respiration (when animals breathe out), by plant respiration, or when humans burn fossil fuels. 5. Draw and label a graphic showing your understanding of the carbon cycle. Student graphics will vary, but should include the following concepts: fossil fuel emissions, carbon dioxide in the atmosphere, carbon dioxide in decaying matter, carbon dioxide in fossil fuels underground, plants use of carbon during photosynthesis, animals obtaining carbon from plants, animal respiration, and plant respiration. Information References: Unknown. (n.d.). The carbon cycle. Retrieved from http://www.kidsgeo.com/geography-for-kids/0159the-carbon-cycle.php ©2012, TESCCC
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Biology HS/Science Unit: 02 Lesson: 02
Johnson, R. (Nov, 2010 07). The carbon cycle. Retrieved from http://www.windows2universe.org/earth/Water/co2_cycle.html Gardner, L. and Genyuk, J.. (n.d.). The carbon cycle game. Retrieved from http://www.windows2universe.org/earth/climate/carbon_cycle.html
©2012, TESCCC
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