Question 1: Define the term 'artery' and explain its main characteristics.

Answer: An artery is a blood vessel that carries blood away from the heart; it has thick, elastic walls to withstand high pressure.

Question 2: Describe the primary function of capillaries in the circulatory system.

Answer: Capillaries facilitate the exchange of gases, nutrients, and waste products between blood and body tissues due to their thin walls.

Question 3: Explain how the structure of veins differs from that of arteries and why.

Answer: Veins have thinner walls, less elastic tissue, and contain valves to prevent backflow, accommodating lower pressure blood flow back to the heart.

Question 4: Calculate the velocity of blood flow if a capillary with a cross-sectional area of 0.002 m² has a blood flow rate of 0.0001 m³/s.

Answer: Velocity = flow rate / cross-sectional area = 0.0001 / 0.002 = 0.05 m/s

Question 5: Identify three safety precautions to consider when studying blood vessel dissections in a laboratory setting.

Answer: Wear protective gloves and eye protection, handle specimens carefully to avoid cuts, and dispose of biological waste properly.

Question 6: Describe the process of how the structure of an artery enables it to handle high-pressure blood flow.

Answer: Arteries have thick, elastic walls composed of smooth muscle and elastic tissue, allowing them to stretch and recoil with each heartbeat, which helps maintain high-pressure blood flow and prevent vessel rupture.

Question 7: In an experiment, it was observed that blood flow velocity in an artery is approximately 0.3 m/s, while in a capillary it drops to 0.05 m/s. Explain why this change in velocity occurs.

Answer: The decrease in velocity occurs because the total cross-sectional area of capillaries is much greater than that of arteries, leading to a slower flow to facilitate exchange of gases and nutrients with tissues.

Question 1: A patient’s blood pressure is measured at 120/80 mmHg. Explain the significance of these values in relation to blood vessel function.

Answer: The systolic pressure (120 mmHg) indicates the pressure during heartbeats, while diastolic (80 mmHg) shows pressure when the heart is at rest; these values reflect healthy vessel elasticity and function.

Question 2: A scenario describes narrowing of arteries due to plaque buildup. Describe how this affects blood flow and the potential health risks involved.

Answer: Narrowing of arteries increases resistance to blood flow, leading to higher blood pressure, reduced oxygen supply to tissues, and increases the risk of heart attacks, strokes, and other cardiovascular diseases.

Question 3: Multiple Choice: Which type of blood vessel is primarily responsible for nutrient exchange?

Answer: Capillaries