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Biofuels Vs Fossil Fuels Unit Has Students Explore the Similarities and Differences Between Fossil Fuels and Biofuels

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Biofuels Vs Fossil Fuels Unit Has Students Explore the Similarities and Differences Between Fossil Fuels and Biofuels Biofuels vs Fossil Fuels The Biofuels vs Fossil Fuels unit has students explore the similarities and differences between fossil fuels and biofuels. In the process, students investigate the carbon-transforming processes of combustion, photosynthesis, fermentation and respiration. They apply their knowledge of these processes to the global carbon cycle to examine how use of fossil fuels and biofuels have different effects on atmospheric carbon dioxide levels and consequently global climate change. Students use their understanding of the global carbon cycle to study the claim that biofuels such as ethanol made from plant material, can help reduce the rate of increase of atmospheric carbon dioxide. In addition, students examine the environmental impact of biofuels agriculture. Overall, this unit has three important goals. These focus on: 1. Matter and energy changes associated with the carbon-transforming processes. 2. The effects of the use of fossil fuels and biofuels on the global carbon cycle and global climate change. 3. A cost/benefit analysis of the production and use of biofuels. This is meant to be a stand-alone unit, however we strongly recommend that teachers use the Biofuels Supplement, a shorter version, along with the entire suite of Carbon TIME units. Our research shows that students need this type of sustained instruction to master systematic thinking about matter and energy in biological and geological systems. Principal Authors Joyce Parker, Great Lakes Bioenergy Research Center and Department of Geological Sciences, Michigan State University Charles “Andy” Anderson, Department of Teacher Education, Michigan State University Editors Contributing Authors: Elizabeth Xeng de los Santos Illustrations by Craig Douglas Wisconsin Energy Institute – www.energy.wisc.edu/education 1 Acknowledgments This unit is derived from the six units developed by the Carbon TIME project, a partnership including Michigan State University, National Geographic Educational Programs, Seattle Public Schools, and the Natural Resources Ecology Laboratory. Development is supported by the Great Lakes Bioenergy Research Center and the Wisconsin Energy Institute at University of Wisconsin. This research is supported in part by grants from the National Science Foundation: Learning Progression on Carbon-Transforming Processes in Socio-Ecological Systems (NSF 0815993), and Targeted Partnership: Culturally relevant ecology, learning progressions and environmental literacy (NSF-0832173), and CCE: A Learning Progression-based System for Promoting Understanding of Carbon-transforming Processes (DRL 1020187). Additional support comes from the DOE Great Lakes Bioenergy Research Center (DOE BER Office of Science DE- FC02-07ER64494). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation or the United States Department of Energy. Questions? Let us know if you have any questions or concerns regarding this biofuels unit. Send us an email at [email protected]. We’d love to hear from you! Wisconsin Energy Institute – www.energy.wisc.edu/education 2 Table of Contents Unit at a Glance .......................................................................................................................... 4 Unit Goals ................................................................................................................................... 5 Table 1: Next Generation Science Standards .......................................................................... 5 Using crosscutting concepts as lenses for biology ...................................................................... 6 Scientific and engineering practices ........................................................................................... 6 Students’ conceptions of matter and energy ............................................................................. 7 Table 2. Developmental stages of students’ reasoning about matter and energy ................. 7 Lesson 1: Introduction to Fuels .............................................................................................. 8 Lesson 1 Activity 1: Biofuels Pretest ........................................................................................... 8 Lesson 1 Activity 2: Which substances burn? .......................................................................... 11 Lesson 1 Activity 3: Investigating Burning/Combustion ........................................................... 13 Lesson 1 Activity 4: Investigating Plant Growth ....................................................................... 17 Lesson 1 Activity 5: Photosynthesis .......................................................................................... 21 Lesson 1 Activity 6: What do plants do with sugar? ................................................................ 23 Lesson 2: Making the Biofuel, Ethanol .................................................................................. 27 Lesson 2 Activity 1: Yeast Fermentation – Initial Predictions ................................................... 27 Lesson 2 Activity 2: Yeast Fermentation – Observations and Explanations ............................. 31 Lesson 2 Activity 3: Tracing Matter and Energy Through Fermentation .................................. 34 Lesson 3: Fuels and the Global Carbon Cycle ........................................................................ 40 Lesson 3 Activity 1: Finding the Carbon .................................................................................... 40 Lesson 3 Activity 2: The Global Carbon Cycle .......................................................................... 44 Lesson 3 Activity 3: Biofuels vs Fossil Fuels .............................................................................. 47 Lesson 4: A Closer Look at Biofuels ...................................................................................... 51 Lesson 4 Activity 1: Alternative Sources of Sugar for Ethanol Production ............................... 51 Lesson 4 Activity 2: Do biofuels help? A closer look ................................................................ 55 Lesson 4 Activity 3: Biofuels Agriculture .................................................................................. 56 Wisconsin Energy Institute – www.energy.wisc.edu/education 3 Unit at a Glance Lesson 1 – Introduction to Fuels • Activity 1.1 Biofuels Pretest • Activity 1.2 Which substances burn? • Activity 1.3 Investigating burning/combustion • Activity 1.4 Investigating plant growth • Activity 1.5 Photosynthesis • Activity 1.6 How can plants make more plants (respiration, digestion, biosynthesis) Lesson 2 – Introduction to Biofuels and Fermentation • Activity 2.1 Yeast Fermentation – Initial Predictions • Activity 2.2 Yeast Fermentation – Observations and Explanations • Activity 2.3 Tracing Matter and Energy Through Fermentation. Lesson 3 – Fuels and the Global Carbon Cycle • Activity 3.1 Finding the Carbon • Activity 3.2 The Global Carbon Cycle • Activity 3.3 Biofuels vs Fossil Fuels Lesson 4 – A Closer Look at Biofuels • Activity 4.1 Alternative sources of sugar for ethanol fermentation • Activity 4.2 Can biofuels help? A closer look • Activity 4.3 Biofuels Agriculture Wisconsin Energy Institute – www.energy.wisc.edu/education 4 Unit Goals Table 1 shows the Next Generation Science Standards (NGSS) addressed by this unit. Table 1: Next Generation Science Standards Lesson NGSS Performance Standards 1 Introduction to MS-PS1-5. Develop and use a model to describe how the total number of atoms does not fuels change in a chemical reaction and thus mass is conserved. HS-PS1-4. Develop a model to illustrate that the release or absorption of energy from a chemical reaction system depends upon the changes in total bond energy. HS-LS1-5. Use a model to illustrate how photosynthesis transforms light energy into stored chemical energy. HS-LS1-7. Use a model to illustrate that cellular respiration is a chemical process whereby the bonds of food molecules and oxygen molecules are broken and the bonds in new compounds are formed resulting in a net transfer of energy. HS-LS1-6. Construct and revise an explanation based on evidence for how carbon, hydrogen, and oxygen from sugar molecules may combine with other elements to form amino acids and/or other large carbon-based molecules. 2 Biofuels & HS-LS2-3. Construct and revise an explanation based on evidence for the cycling of matter Fermentation and flow of energy in aerobic and anaerobic conditions. MS-PS1-5. Develop and use a model to describe how the total number of atoms does not change in a chemical reaction and thus mass is conserved. HS-PS1-4. Develop a model to illustrate that the release or absorption of energy from a chemical reaction system depends upon the changes in total bond energy. 3 Global Carbon 5-LS2-1. Develop a model to describe the movement of matter among plants, animals, Cycle decomposers, and the environment. MS-LS2-3. Develop a model to describe the cycling of matter [carbon] and flow of energy among living and nonliving parts of an ecosystem. HS-LS2-5. Develop a model to illustrate the role of photosynthesis and cellular respiration in the cycling of carbon among the biosphere, atmosphere, hydrosphere, and geosphere. HS-LS2-7. Design, evaluate, and refine a solution for reducing the impacts of human activities on the environment and biodiversity. MS-ESS3-5. Ask questions to clarify
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