Question 1: Define aerobic respiration and explain where it occurs in eukaryotic cells.

Answer: Aerobic respiration is a process that releases energy by breaking down glucose in the presence of oxygen, primarily occurring in the mitochondria of eukaryotic cells.

Question 2: Describe the role of oxygen in aerobic respiration.

Answer: Oxygen acts as the final electron acceptor in the electron transport chain, allowing the process to produce a large amount of ATP efficiently.

Question 1: List the three main stages of aerobic respiration in order.

Answer: Glycolysis, the Krebs cycle, and the electron transport chain.

Question 2: Explain what occurs during glycolysis and where it takes place.

Answer: Glycolysis is the breakdown of one glucose molecule into two molecules of pyruvate, producing a net gain of 2 ATP and 2 NADH molecules, and occurs in the cytoplasm.

Question 1: Calculate the total amount of ATP produced from complete oxidation of one molecule of glucose during aerobic respiration. (Use the approximate values: Glycolysis = 2 ATP, Krebs cycle = 2 ATP, Electron transport chain = 32 ATP).

Answer: 36 ATP

Question 2: A student measures the oxygen consumption during respiration and finds it to be 0.5 litres per minute. If the organism respires for 30 minutes, how much oxygen is consumed in total? (Use SI units, 1 litre = 0.001 m³).

Answer: 0.015 m³

Question 1: Design a simple experiment to measure the rate of aerobic respiration in yeast. Include the variables you would control and how you would measure the respiration rate.

Answer: I would measure the production of carbon dioxide by placing yeast in a respirometer with a fixed amount of glucose, controlling temperature and pH, and measuring the volume of CO₂ produced over time.

Question 2: What safety precautions should be taken when conducting experiments involving yeast and biochemical reagents?

Answer: Wear safety goggles, handle reagents with care, dispose of biological waste properly, and work in a well-ventilated area.

Question 1: A researcher finds that increasing oxygen concentration from 20% to 40% in a controlled environment increases the rate of respiration in bacteria by 50%. Explain the reason for this observation.

Answer: Higher oxygen levels facilitate more efficient electron transport in respiration, increasing ATP production and thus increasing the respiration rate.

Question 2: Explain how understanding aerobic respiration can be applied in the food industry or biotechnology.

Answer: Knowledge of aerobic respiration allows industries to optimise conditions for microbial fermentation, improve energy efficiency in bioreactors, and develop biofuel production processes by controlling oxygen levels to maximise yield.