Question 1: Define metabolism in the context of cellular respiration.

Answer: Metabolism refers to all the chemical reactions occurring within a cell, including those involved in breaking down nutrients to release energy and synthesising necessary compounds.

Question 2: Describe the main stages of aerobic respiration and where they occur in the cell.

Answer: The main stages are glycolysis in the cytoplasm, the Krebs cycle in the mitochondria, and oxidative phosphorylation on the inner mitochondrial membrane.

Question 3: Explain how energy is transferred during cellular respiration.

Answer: Energy is transferred by the conversion of ADP to ATP through substrate-level phosphorylation and oxidative phosphorylation, driven by the flow of electrons through the electron transport chain.

Question 1: Calculate the amount of ATP produced from the complete oxidation of 1 mole of glucose (C6H12O6) during aerobic respiration. Assume 36 ATP molecules are produced per glucose molecule.

Answer: 36 ATP molecules

Question 2: If a cell produces 2.5 mmol of glucose per hour, how many mmol of ATP are generated in that time? (Use the average yield of 36 ATP per glucose).

Answer: 90 mmol of ATP

Question 1: Describe a simple experiment to measure the rate of respiration in germinating peas. Include variables you would control and safety precautions.

Answer: The experiment involves placing germinating peas in a respirometer to measure oxygen consumption over time. Controlled variables include temperature, volume of air, and seed size. Safety precautions include handling seeds hygienically, ensuring the apparatus is secure to prevent leaks, and disposing of biological materials properly.

Question 1: A study shows that athletes' resting metabolic rates vary between individuals. The data indicates some individuals consume 1500 kcal/day, while others consume 2000 kcal/day. Explain what factors might account for these differences.

Answer: Differences may be due to variations in muscle mass, age, sex, genetics, activity levels, and metabolic efficiency. Higher muscle mass increases resting energy expenditure, while age and sex also influence metabolic rate.

Question 1: Explain how understanding human metabolism can aid in developing treatments for metabolic disorders such as diabetes.

Answer: Understanding metabolism helps identify how insulin regulates glucose uptake and energy use. It can lead to targeted therapies to improve insulin sensitivity or regulate blood sugar levels in disorders like diabetes.

Question 2: Discuss how knowledge of metabolic processes is utilised in industries such as biotechnology or agriculture.

Answer: In biotechnology, metabolic engineering is used to optimise microbial production of antibiotics, enzymes, or biofuels. In agriculture, understanding plant metabolism aids in developing crops with higher yield, disease resistance, or tolerance to environmental stresses.