Anaerobic Respiration
Overview
Sometimes a cell needs energy but cannot get oxygen fast enough, for example a sprinter's leg muscles or a yeast cell deep in dough. In these situations cells switch to anaerobic respiration, releasing energy without oxygen, though at a cost.
In this lesson you will learn what anaerobic respiration is, why it gives so much less energy than aerobic respiration, and the different products it makes in yeast and in human muscle. You will also meet the idea of an oxygen debt, the price your body pays for exercising anaerobically.
Objectives
- Describe anaerobic respiration as the chemical reactions in cells that break down nutrient molecules to release energy without using oxygen
- State that anaerobic respiration releases much less energy per glucose molecule than aerobic respiration
- State the word equation for anaerobic respiration in yeast as: glucose → alcohol + carbon dioxide
- State the word equation for anaerobic respiration in muscles during vigorous exercise as: glucose → lactic acid
- [Supplement] State the balanced chemical equation for anaerobic respiration in yeast as: C H O → 2C H OH + 2CO 6 12 6 2 5 2
- [Supplement] State that lactic acid builds up in muscles and blood during vigorous exercise causing an oxygen debt
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Lesson Evaluation
Congratulations on completing the lesson on Anaerobic Respiration. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.
You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.
Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.
- The products of anaerobic respiration in yeast are: A. carbon dioxide and water B. lactic acid only C. alcohol and carbon dioxide D. glucose and oxygen Answer: C
- The product of anaerobic respiration in human muscle is: A. alcohol B. lactic acid C. carbon dioxide D. water Answer: B
- Compared with aerobic respiration, anaerobic respiration releases: A. more energy per glucose B. the same energy per glucose C. much less energy per glucose D. no energy Answer: C
- The balanced equation for anaerobic respiration in yeast is: A. C6H12O6 + 6O2 -> 6CO2 + 6H2O B. C6H12O6 -> 2C2H5OH + 2CO2 C. C6H12O6 -> lactic acid D. 2C2H5OH -> C6H12O6 Answer: B
- Lactic acid building up in muscles during exercise causes: A. a glucose debt B. an oxygen debt C. a carbon dioxide debt D. a water debt Answer: B
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