Question 1: Define the term 'artery' and describe its main function in the circulatory system.

Answer: An artery is a blood vessel that carries oxygen-rich blood away from the heart to body tissues. Its main function is to transport oxygenated blood under high pressure.

Question 2: Explain how the structure of capillaries allows for efficient exchange of gases and nutrients.

Answer: Capillaries have very thin walls made of single-layer endothelial cells, which facilitate the diffusion of gases, nutrients, and waste products between blood and tissues.

Question 3: Multiple Choice: Which type of blood vessel has the thickest muscular wall?

Answer: B

Question 1: Calculate the total blood flow rate (in mL/min) through a vessel if the flow velocity is 30 cm/sec and the cross-sectional area is 0.5 cm². (Use the formula: Flow Rate = Velocity × Area).

Answer: Flow Rate = 30 cm/sec × 0.5 cm² = 15,000 mL/min

Question 1: Describe a safe and ethical way to simulate blood flow in an experiment to study how vessel diameter affects flow rate.

Answer: A safe method involves using fluid in transparent tubing with adjustable diameters, ensuring no harmful substances are used. The experiment should be conducted with proper supervision, avoiding pressure overloads, and using non-toxic, inert fluids like water or glycerin. Variables should include vessel diameter, and safety precautions involve securing all connections and avoiding sharp edges.

Question 1: A study recorded the blood flow velocity in arteries and veins of a patient. The artery's average velocity was 40 cm/sec, while the vein's was 10 cm/sec. Explain how the differences in vessel structure contribute to these velocity differences.

Answer: Arteries have thicker, more muscular walls and smaller lumens, which maintain higher pressure and velocity. Veins have larger lumens and thinner walls, resulting in lower velocity and pressure.

Question 1: Discuss how the structure of different blood vessels adapts to their specific functions in the circulatory system. Include examples of arteries, veins, and capillaries in your explanation. (6 marks)

Answer: Arteries have thick, elastic, and muscular walls to withstand and maintain high-pressure blood flow away from the heart. Veins have thinner walls with valves to prevent backflow as they carry blood under lower pressure back to the heart. Capillaries have very thin walls to facilitate exchange of gases, nutrients, and waste between blood and tissues, ensuring efficient nutrient delivery and waste removal.

Question 1: Describe how understanding blood vessel properties is important in designing medical treatments such as stents or bypass surgery.

Answer: Knowledge of blood vessel structure helps in designing devices like stents that keep arteries open and in planning surgeries to bypass blocked vessels, ensuring they can withstand blood pressure and facilitate proper blood flow.