Bundle: Biology: The Unity and Diversity of Life, Loose-leaf Version, 14th + LMS Integrated for MindTap Biology, 2 terms (12 months) Printed Access Card
14th Edition
ISBN: 9781305775480
Author: Cecie Starr, Ralph Taggart, Christine Evers, Lisa Starr
Publisher: Cengage Learning
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Chapter 6, Problem 2DAA
Energy Efficiency of Biofuel Production Most of the plant material currently used for biofuel production in the United States consists of food crops—mainly corn, soybeans, and sugarcane. In 2006, David Tilman and his colleagues published the results of a 10-year study comparing the net energy output of various biofuels. The researchers grew a mixture of native perennial grasses without irrigation, fertilizer, pesticides, or herbicides, in sandy soil that was so depleted by intensive agriculture that it had been abandoned. They measured the usable energy in biofuels made from the grasses, and also from com and soy, then measured the energy it took to grow and produce biofuel from each kind of crop (FIGURE 6.18).
FIGURE 6 .18 Energy inputs and outputs of biofuels made from three different crops. One hectare is about 2 .5 acres.
2. Which of the biofuels tested had the highest ratio of energy output to energy input?
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Chapter 6 Solutions
Bundle: Biology: The Unity and Diversity of Life, Loose-leaf Version, 14th + LMS Integrated for MindTap Biology, 2 terms (12 months) Printed Access Card
Ch. 6 - A cat eats a bird, which ate a caterpillar that...Ch. 6 - Plants use__________ as an energy source to drive...Ch. 6 - Most of the carbon dioxide that plants use for...Ch. 6 - Which of the following statements is incorrect? a....Ch. 6 - Prob. 5SQCh. 6 - When a photosystem absorbs light, __________. a....Ch. 6 - Prob. 7SQCh. 6 - What accumulates inside the thylakoid compartment...Ch. 6 - The atoms in the molecular oxygen released during...Ch. 6 - Prob. 10SQ
Ch. 6 - Prob. 1DAACh. 6 - Energy Efficiency of Biofuel Production Most of...Ch. 6 - Energy Efficiency of Biofuel Production Most of...Ch. 6 - The Calvin-Benson cycle starts when a. light is...Ch. 6 - Which of the following substances does not...Ch. 6 - Closed stomata ________. a. limit gas exchange b....Ch. 6 - In C3 plants, ______ makes sugar production...Ch. 6 - Match each with its most suitable description....Ch. 6 - Prob. 1CTCh. 6 - While gazing into an aquarium, you see bubbles...Ch. 6 - AC3 plant absorbs a carbon radioisotope (as part...Ch. 6 - As you learned in this chapter, cell membranes arc...
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