Biomass Energy Exercises

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Exercises I. Essay Questions 1. Why are most plant leaves green? Why do they turn yellow in the fall? 2. What does it mean to “fix” carbon? How can this be done? 3. What is a hydrothermal vent? Why do deep-sea organisms mostly grow near these vents? 4. Describe the processes of aerobic and anaerobic conversion. Give examples of physical activities that involve these conversions. 5. What are the various trophic levels? How does energy transfer from one trophic level to another? 6. What are the differences between thermochemical and biochemical conversions? Between the processes of aerobic and anaerobic conversion? 7. A basketball player is using an average 400 watts of power during a basketball match. How long does he have to play to burn off a Big Mac (750 Calories)? Assume a metabolic efficiency of 25%. 8. What is the BMR value for a 70 kg woman who is 155 cm tall? Is she overweight or underweight? If she is overweight, and if she intends to reduce her weight by aerobics only (no dieting) over 6 months, for how long does she have to exercise every day? 9. If the US were to meet its entire energy need (100 Quads) from sugarcane, how many tons of sugarcane would have to be planted? 10. Describe the difference between gross and net production. What are the factors that limit production efficiency from one trophic level to the next? 11. Which has a higher metabolic rate, a hummingbird or a human? How does size of an animal affect its metabolic rate? II. Multiple Choice Questions 1. Biomass a. Is a form of solar energy b. Can be used to produce electricity c. Refers principally to wood, and animal and human waste d. Will likely increase in use because it is a free source of energy e. All of the above 2. Which of the following are considered to be carbon sequesters? a. Fossil fuels b. The oceans c. Thermafrost and tundra d. The atmosphere e. All of the above 3. During photosynthesis, a plant a. Creates energy b. Absorbs energy c. Gives off energy d. Transmits energy e. Reflects energy 4. Humans use chemical energy contained in food a. To maintain their body temperature b. To enable their bodies to move c. To perform mechanical work d. To feed neurons for transmitting electrical signals e. All of the above 5. Biomass energy refers generally to a. Wood and agricultural products b. Solid waste c. Landfill gases d. Alcohols e. All of the above 6. If 0.1% of solar energy that falls on earth is captured by plants, and 2% of that energy is involved in photosynthesis, what fraction of sunlight that hits the earth is converted to food? a. 0.2 b. 0.02 c. 0.002 139 Chapter 6 - Biomass Energy d. 0.0002 e. 0.00002 7. Which of the following statements is incorrect? a. Autotrophs are mainly green plants and algae formed through photosynthesis. b. Heterotrophs cannot produce their own food. c. Heterotrophs can be divided into herbivores or vegetarians, and carnivores or meat-eaters. d. Nutrients are recycled over and over through biological systems. e. None of the above. 8. What kind of organisms can produce their own food? a. Autotrophs b. Herbivores c. Heterotrophs d. Carnivores e. All of the above 9. Which trophic level is represented by the greatest biomass in any ecosystem? a. Herbivores b. Primary carnivores c. Producers d. Secondary carnivores e. Top carnivores 10. What kind of organisms are at the top of the food web? a. Autotrophs b. Herbivores c. Heterotrophs d. Carnivores e. None of the above 11. If you eat a frog that eats insects, which in turn eat plants, you would be a a. Producer b. Primary consumer c. Secondary consumer d. Tertiary consumer e. Trophic consumer 12. Pyrolysis is a. Burning biomass at a very high temperature b. The process of hydrogenation of biomass by adding steam c. Breaking down the biomass matter by using heat in the absence of oxygen d. Thermochemical conversion at room temperature e. Disintegration by microscopic organisms in the absence of oxygen 13. Wood and other biomass account for about ____percent of US energy consumption. a. 0.1 b. 1 c. 3 d. 10 e. 25 14. Respiration is a. An intermediate step in photosynthesis b. Another name for photosynthesis c. The reverse of photosynthesis d. Same as sweating e. Photosynthesis in water 15. Incineration a. Is becoming the most popular way to produce energy at very low costs b. Is considered as a good and inexpensive alternative to solid waste disposal c. Is not clean and produces harmful by-products that are highly toxic to humans and animals d. Is best for disposing of metals and plastics e. All of the above 16. “Rule of 10” refers to a hypothesis that states a. Roughly 10% of solar energy is involved in photosynthesis b. Biomass constitutes about 10% of US energy needs c. Humans use about 10% of their daily energy needs from food d. Only 10% of the energy contained in a given trophic level can be converted to the level below e. Humans convert roughly 10% of the energy contained in their food to useful muscle work 140 17. The human body works as a heat engine, converting ______ percent of the food energy to mechanical energy necessary to carry daily physical activities, while disposing the rest as waste heat. a. Less than 1% b. Between 1 to 5% c. About 15-25% d. About 60% e. Above 90% 18. Thermal treatment of biomass to methane is called a. Pyrolysis b. Incineration c. Fermentation d. Burning e. Decomposition 19. Which of the following statements is not correct? a. Body mass index is a measure of body’s mass in proportion to height. b. Body mass index is calculated as body mass divided by height. c. Body mass index is calculated as body mass divided by height squared. d. According to the National Institute of Health studies, a healthy body should have a body mass index of between 19 and 25. e. None of the above. 20. The minimum energy required for a body to maintain all its vital organs function under rest is called a. Body mass index b. Basal metabolic rate c. Body’s maximum respiration d. Survival index e. None of the above III. True or False? 1. Biomass accounts for almost all the renewable energy used in the United States. 2. When burned, biomass does not contribute to any greenhouse gases. 3. Biodiversity refers to the number of species present in a given place at a given time. 4. Photosynthesis is possible only in air and in the presence of sunlight. 5. Photosynthesis was the first process to occur in nature after earth sufficiently cooled down, following its formation 5 billion years ago. 6. Heterotrophs are organisms that cannot produce their own food, but are fed by other organisms. 7. An organism which is fed by a producer is called a secondary consumer. 8. Autotrophs are placed at the base of food pyramid and are responsible for primary food production. 9. Net productivity is the gross productivity minus that which is metabolized by the producer. 10. BMR is generally higher for males and for heavier and healthier animals. 11. For two persons of a similar mass, the BMI is lower for the person who is taller. 12. To use 200 kilocalories in muscle energy, you need between 800-1000 kcal in food energy. 13. Biomass is a type of solar energy. 14. Biomass is stored chemical energy in plants. 15. Humans can convert about one-half of the energy contained in food they eat to muscle work. IV. Fill in the Blanks 1. In addition to chlorophyll, plants trap light via two other pigments called ___________ and ______________. 2. The reverse process to photosynthesis where carbohydrate and oxygen react to produce carbon dioxide and water is called _______. 3. Half of all metabolic activities happen in two organs in the body: the ________ and the ________. 141 Chapter 6 - Biomass Energy 4. The three major food categories are _________, ____________, and ____________. 5. Roughly two-thirds of garbage from American households is made of _________. V. Project I - Creationism and Evolution How life was formed has been debated by scientists and theologians for a long time, without reaching consensus. Scientists strongly favor the theory of evolution as laid out by the noted British biologist, Charles Darwin (1809-1882). Theologians, however, believe that the odds of amino acids combining to form the necessary proteins by undirected means is so minute that the proteins needed for life could never have come into existence by chance or any natural processes. In this project you are asked to research arguments for and against each theory and answer the following questions: a. What constitutes life? How can we distinguish living from non-living organisms? b. How do different religions (Buddhism, Judaism, Christianity, Islam, etc.) view the origin of life? Are there any discrepancies among these religions in this regard? c. Is there any contradiction between Christianity and the theory of evolution? Explain. d. What are the main features distinguishing evolutionists and creationists in regard to the origin of life? e. Is there a scientific basis for the creationists’ point of view? What are they? Do these arguments withstand the accepted methods of scientific inquiry? f. How does the doctrine of “Intelligent Design” differ from traditional creationists? g. Does science rule out divine intervention? Project II - Life in the Universe Life as we know it is made of mainly four elements -- oxygen, carbon, hydrogen and nitrogen. A few other elements, notably calcium, phosphorous, potassium and sulfur, provide the bulk of nutrients we need to sustain life. Most oxygen is bound to hydrogen to form water, whereas carbon makes up cellular structure. In this project you are asked to research the web resources to find whether other forms of life can or cannot be sustained on Earth or any other place on the Universe. In particular try to answer the following questions: 1. What is unique about carbon that makes it so suitable for forming much of the internal structure of living organisms on Earth? (Hint: look at molecular structure of carbon and how it binds with other molecules). 2. Why do some scientists (and science-fiction writers) propose other forms of life, especially those based on silicon, as a possibility? Why is carbon-based life more prevalent over silicon-based life? What makes silicon less favorable? 3. What other elements have been suggested and why? 4. Why it is highly unlikely to have any other form of life such as nitrogen-based or iron-based life forms in the universe? Project III - Diet and Exercise In this project you are asked to keep a daily log of your daily food intake and tasks you perform. Then you are asked to estimate your caloric intake and the calories you burn as a result of daily routine, work, and exercise. For better estimates, it is recommended that you collect and average data for three 24-hour periods. Basic Information: Sex: _____ (male/female) Mass: _____ kg Height: _____ cm 1. Make a table listing all the foods you consumed. Categorize them into breakfast, lunch, dinner, and snacks. 2. Make a list the activities you performed and their durations. Now do the following calculations: 1. Find the average daily total intake of food calories. Take the three-day average. 2. Estimate the average daily total calories from carbohydrates, protein, and fat, respectively. Assume 9 Calories per gram of fat and 4 Calories 142 per gram of protein and carbohydrates. 3. Calculate the average power you put out assuming you maintain a similar diet throughout the year. 4. Calculate your BMR. According to Harris and Benedict19, BMR can be accurately calculated using the following equations. BMR is basal metabolic rate in kcal/day; M is body mass in kg, H is height in cm, and A is age in year. Men: BMR= 66 +13.7*M +5*H -6.8*A Women: BMR=655 +9.6*M +1.8*H -4.7*A 5. Estimate the total non-BMR calories burned through various activities. Which of the activities were aerobic and which ones were anaerobic? 6. Calculate your total daily energy expenditure by adding total BMR and non-BMR calories. What is power per mass (kW/kg)? 7. Carry the energy balance by taking the difference between your daily energy expenditure and energy from food intake. 8. Calculate your daily calorie needs by multiplying your BMR by: a. 1.200 if you are inactive (do little or no exercise) b. 1.375 if you are somewhat inactive (light exercise 1-3 times a week) c. 1.550 if you are moderately active (moderate exercise 3-5 times a week) d. 1.725 if you are active (extraneous exercise 5-7 times a week) 9. If you maintain a fairly similar routine for the entire year, how much mass should you expect to gain or to lose? 19 Harris, J. A. and Benedict, F., “A Biometric Study of Basal Metabolism in Man,” Washington, D.C. The Carnegie Institution, 1919.

  • (a/n) aerobic/anaerobic

Work Sheet for Project III Name: ___________________ Mass: ______ kg Height: _______ m Sex: ___ Food Intake: Breakfast: Calories Snack Calories _______________ _______ _______________ _______ _______________ _______ _______________ _______ _______________ _______ _______________ _______ Lunch Calories Dinner Calories _______________ _______ _______________ _______ _______________ _______ _______________ _______ _______________ _______ _______________ _______ Total: ______ Calories _______________ _______ _______________ _______ Activities: Activity Calories Activity Calories (a/n)* Sleeping _______ Light exercise Sitting/Watching TV _______ __________ _______ ( __ ) Walking _______ __________ _______ ( __ ) Reading _______ Medium exercise Total BMR: ____________ Calories Driving _______ __________ _______ ( __ ) Total non-BMR: ________ Calories Cooking _______ __________ _______ ( __ ) Total: _______________ Calories Washing dishes _______ Strenuous exercise Working: (describe) _______ __________ _______ ( __ ) __________ _______ __________ _______ ( __ ) Power per kilogram: ____________ kW/kg Net Energy Intake: ____________ Calories Mass gain / loss: ____________ kg Calorie needs _____________ kilocalories