Question 1: Define anaerobic respiration and explain how it differs from aerobic respiration.

Answer: Anaerobic respiration is a type of respiration that occurs without oxygen, producing energy, typically in cells when oxygen is scarce. Unlike aerobic respiration, which uses oxygen and produces more energy, anaerobic respiration produces less energy and results in by-products like lactic acid or alcohol.

Question 2: Describe the main chemical process of anaerobic respiration in human muscle cells.

Answer: In human muscle cells, anaerobic respiration converts glucose into lactic acid and a small amount of energy (ATP) without using oxygen.

Question 3: Which by-product is mainly produced during anaerobic respiration in yeast?

Answer: Ethanol

Question 4: Fill in the blank: During anaerobic respiration in muscles, the by-product produced is ________.

Answer: lactic acid

Question 5: List two differences between aerobic and anaerobic respiration.

Answer: Aerobic respiration requires oxygen and produces more energy (ATP), while anaerobic respiration does not require oxygen and produces less energy, often resulting in by-products such as lactic acid or alcohol.

Question 6: Calculate the amount of ATP produced during the anaerobic respiration of one molecule of glucose. Show your working.

Answer: During anaerobic respiration, 2 ATP molecules are produced per glucose molecule.

Question 7: Identify three variables that could affect the rate of anaerobic respiration in a controlled experiment.

Answer: Presence of glucose, temperature, and pH levels.

Question 8: State two safety precautions that should be taken when conducting experiments related to anaerobic respiration.

Answer: Wear protective gloves and goggles; ensure proper ventilation to avoid buildup of gases.

Question 9: A sample of yeast undergoes fermentation, producing 2 mL of ethanol and 4 mL of carbon dioxide. What does this data suggest about the process and its by-products?

Answer: The data indicates that yeast fermentation is producing ethanol and carbon dioxide as by-products, typical of anaerobic respiration in yeast cells.

Question 10: In industries like brewing and baking, anaerobic respiration is utilized. Explain one benefit and one limitation of using anaerobic respiration in these industries.

Answer: A benefit is that anaerobic respiration allows for the production of alcohol in brewing and leavening in baking without the need for oxygen. A limitation is that it produces less energy compared to aerobic processes, which can limit efficiency and scale.