Question 1: Describe the main role of the heart in the cardio-respiratory system during exercise.

Answer: The heart pumps oxygenated blood from the lungs to the muscles and deoxygenated blood back to the lungs for oxygenation, ensuring muscles receive sufficient oxygen during exercise.

Question 2: Explain how the respiratory system supports physical activity.

Answer: The respiratory system supplies oxygen to the blood and removes carbon dioxide from the body, supporting energy production and maintaining pH balance during physical activity.

Question 3: Identify and describe the function of the lungs within the cardio-respiratory system.

Answer: The lungs facilitate gas exchange by taking in oxygen from inhaled air and expelling carbon dioxide during exhalation.

Question 4: Explain what happens to the heart rate and breathing rate during vigorous exercise.

Answer: Both heart rate and breathing rate increase to deliver more oxygen to the muscles and remove waste gases more efficiently.

Question 5: Describe the pathway of oxygen from the air to the muscles during exercise.

Answer: Oxygen enters the lungs during inhalation, diffuses into the blood in the alveoli, binds to haemoglobin in red blood cells, is transported via the circulatory system, and is delivered to muscle cells for energy production.

Question 6: Sketch a simple diagram of the flow of blood through the heart, lungs, and body. Label the key parts involved.

Answer: A correct sketch would include the right atrium, right ventricle, lungs (for oxygenation), left atrium, left ventricle, and the aorta, with arrows showing the direction of blood flow.

Question 7: List three ways regular aerobic exercise can improve the efficiency of the cardio-respiratory system.

Answer: Increased stroke volume, lower resting heart rate, improved lung capacity.

Question 8: Sketch a diagram of the alveoli within the lungs. Indicate where gas exchange occurs.

Answer: A detailed sketch would show clusters of tiny air sacs (alveoli) with thin walls, surrounded by capillaries, demonstrating gas exchange between air and blood.

Question 9: What is the significance of the capillaries surrounding the alveoli?

Answer: Capillaries allow for the exchange of oxygen and carbon dioxide between the air in the alveoli and the blood in the circulatory system.

Question 10: Explain how the body's response to increased exercise intensity affects the cardio-respiratory system.

Answer: As exercise intensity increases, heart rate and stroke volume increase to pump more blood, while breathing rate rises to meet the higher oxygen demand and remove carbon dioxide more rapidly.

Question 11: Describe the effect of regular cardio exercise on resting heart rate over time.

Answer: Regular cardio exercise leads to a lower resting heart rate as the heart becomes more efficient and pumps a greater volume of blood with each beat.