Question 1: Briefly explain the primary function of the human heart within the circulatory system.

Answer: The human heart pumps blood throughout the body, delivering oxygen and nutrients and removing waste products.

Question 2: List the four main chambers of the heart in the order blood flows through them, starting from the right atrium.

Answer: Right atrium, right ventricle, left atrium, left ventricle.

Question 3: Which chamber of the heart has the thickest muscular wall, and why?

Answer: The left ventricle, because it needs to generate a high force to pump blood throughout the entire body.

Question 4: Fill in the blank: The valves between the atria and ventricles are called __________ valves, and they prevent backflow of blood into the atria during ventricular contraction.

Answer: atrioventricular

Question 5: Describe the role of the septum in the heart.

Answer: The septum is a muscular wall that separates the left and right chambers of the heart, preventing the mixing of oxygenated and deoxygenated blood.

Question 6: Multiple Choice: Which vessel carries oxygenated blood from the lungs to the heart?

Answer: Pulmonary vein

Question 7: Calculate the total volume of blood pumped by the heart in one minute if the stroke volume is 70 ml and the heart rate is 75 beats per minute. Show your working.

Answer: Total volume = Stroke volume × Heart rate = 70 ml × 75 = 5250 ml or 5.25 litres.

Question 8: Identify two safety precautions or considerations when studying the structure of the heart in a laboratory setting.

Answer: Using proper personal protective equipment (PPE) such as gloves and goggles; ensuring ethical sourcing of specimens.

Question 9: Describe how the structure of the ventricles supports their function in blood circulation.

Answer: The ventricles have thick muscular walls, especially the left ventricle, enabling them to generate high pressure necessary to pump blood either to the lungs via the right ventricle or throughout the body via the left ventricle. This structural adaptation ensures efficient circulation and maintains blood pressure.

Question 10: Explain how the structure of the heart's valves contributes to unidirectional blood flow.

Answer: The valves are one-way structures that open to allow blood flow in only one direction and close to prevent backflow, ensuring blood moves efficiently through the heart and circulatory system.

Question 11: In modern medicine, how has understanding of heart structure contributed to the development of artificial heart valves?

Answer: Knowledge of the heart's valve structure has enabled the design of artificial valves that mimic natural function, improving treatment options for valve diseases and restoring normal blood flow.