Question 1: Define homeostasis and explain its importance in maintaining stable body temperature.

Answer: Homeostasis is the process by which the body maintains a stable internal environment, including body temperature, despite external changes. It is essential for optimal enzyme function and overall health.

Question 2: Describe two mechanisms the human body uses to regulate body temperature when it is too high.

Answer: Sweating to cool the body through evaporation and vasodilation to increase blood flow near the skin surface for heat loss.

Question 3: In an automotive cooling system, what is the purpose of the thermostat?

Answer: The thermostat regulates the engine temperature by controlling coolant flow, ensuring the engine operates within an optimal temperature range.

Question 4: Calculate the heat energy (in joules) required to raise the temperature of 5 litres of water from 20°C to 80°C. (Specific heat capacity of water = 4200 J/kg°C)

Answer: Q = mcΔT; Q = 5 kg × 4200 J/kg°C × (80°C - 20°C) = 5 × 4200 × 60 = 1,260,000 Joules

Question 5: Identify two variables that a car’s temperature regulation system might monitor to maintain optimal engine temperature.

Answer: Coolant temperature and engine oil temperature.

Question 6: Explain why an automotive cooling system needs a radiator cap that can withstand high pressure.

Answer: Because the coolant expands as it heats up, creating high pressure; the cap prevents coolant loss and maintains system pressure to improve heat transfer.

Question 7: Describe a safety precaution that should be observed when handling automotive coolant.

Answer: Avoid direct contact with coolant as it is toxic; wear gloves and eye protection, and dispose of used coolant properly.

Question 8: A car's cooling system shows a rise in coolant temperature from 90°C to 105°C during operation. What might this indicate about the system's functioning?

Answer: It could indicate that the radiator is blocked, the thermostat is stuck closed, or the coolant pump is malfunctioning, leading to overheating.

Question 9: Analysing a scenario: An automotive cooling system maintains an engine temperature of approximately 95°C. If ambient temperature drops significantly, how should the system respond to maintain engine efficiency?

Answer: The system should adjust by increasing coolant flow or activating additional cooling fans to dissipate heat more effectively, ensuring the engine remains at optimal temperature despite cooler ambient conditions.

Question 10: Outline a simple experiment to test the effectiveness of different types of automotive coolant in maintaining engine temperature. Include variables, safety precautions, and expected outcomes.

Answer: Variables: Type of coolant (independent), engine temperature over time (dependent). Control variables: engine type, ambient temperature, engine load. Safety precautions include wearing protective gloves and eye protection, ensuring proper disposal of coolants. Expected outcome: Coolants with higher heat capacity or better heat transfer properties will maintain lower and more stable engine temperatures over time.

Question 11: Discuss how the principles of homeostasis in body temperature are similar to or different from the regulation of engine temperature in a vehicle.

Answer: Both systems aim to maintain a stable temperature despite external changes. In the body, mechanisms like sweating and vasodilation help dissipate heat, while in a vehicle, coolant circulation and radiator function achieve similar results. However, biological responses are controlled by feedback loops involving hormones and nerve signals, whereas automotive systems rely on mechanical and electronic sensors and components. The biological system is adaptive and self-regulating, while the automotive system requires external controls and maintenance.