Question 1: Define the process of gas exchange in the human respiratory system.

Answer: Gas exchange is the process where oxygen is absorbed into the blood and carbon dioxide is expelled from the blood in the alveoli of the lungs.

Question 2: Explain how the structure of alveoli facilitates efficient gas exchange.

Answer: Alveoli have thin walls and a large surface area, which allows for efficient diffusion of gases between the lungs and blood.

Question 3: What is the primary function of hemoglobin in gas exchange?

Answer: Hemoglobin binds to oxygen in the lungs and transports it to body tissues, facilitating oxygen delivery.

Question 1: Calculate the amount of oxygen (in liters) absorbed by the blood if a person inhales 0.5 liters of air with 21% oxygen, and 80% of the oxygen diffuses into the blood.

Answer: 0.084 liters

Question 2: Using the formula Lung Capacity = Tidal Volume + Inspiratory Reserve Volume + Expiratory Reserve Volume + Residual Volume, calculate the total lung capacity if tidal volume is 0.5 liters, inspiratory reserve volume is 2.5 liters, expiratory reserve volume is 1.0 liters, and residual volume is 1.2 liters.

Answer: 5.2 liters

Question 1: Describe a simple experiment to measure the effect of exercise on lung capacity. Include the variables involved and safety precautions to consider.

Answer: A possible experiment involves measuring lung capacity before and after exercise using a spirometer. The independent variable is exercise intensity; the dependent variable is lung capacity. Control variables include age and health status. Safety precautions include ensuring participants are healthy and monitoring for signs of overexertion.

Question 1: A patient’s blood gas analysis shows a lower than normal oxygen level and higher carbon dioxide level. Explain what this indicates about their lung function and possible respiratory issues.

Answer: It indicates impaired gas exchange, possibly due to conditions like COPD or pneumonia, leading to less oxygen entering the blood and less carbon dioxide being expelled.

Question 1: Describe the role of the diaphragm and intercostal muscles during inhalation and exhalation. (6 marks)

Answer: During inhalation, the diaphragm contracts and moves downward, while the intercostal muscles contract to lift the rib cage, increasing thoracic volume and reducing pressure, allowing air to flow in. During exhalation, the diaphragm relaxes and moves upward, and the intercostal muscles relax, decreasing thoracic volume and increasing pressure, forcing air out.

Question 1: Explain how knowledge of gas exchange principles is used in the design of artificial lungs or ventilators.

Answer: Artificial lungs and ventilators are designed to mimic natural gas exchange by providing a surface for oxygen to enter the blood and carbon dioxide to be removed, using diffusion principles to support patients with compromised lung function.