Question 1: Define the term 'alveolus' and explain its role in the respiratory system.

Answer: An alveolus is a tiny air sac in the lungs where gas exchange occurs; it allows oxygen to enter the blood and carbon dioxide to be removed.

Question 2: Describe the pathway of air from the trachea to the alveoli.

Answer: Air passes from the trachea into bronchi, then into smaller bronchioles, and finally reaches the alveoli where gas exchange occurs.

Question 3: What is the function of the diaphragm in the process of breathing?

Answer: The diaphragm contracts and flattens during inhalation to increase thoracic volume, enabling air to enter the lungs.

Question 1: If a person's tidal volume is 0.5 litres and their respiratory rate is 12 breaths per minute, what is their minute ventilation in litres per minute? Show your calculation.

Answer: Minute ventilation = tidal volume × respiratory rate = 0.5 L × 12 = 6 litres per minute.

Question 2: A student inhales 0.6 litres of air per breath and exhales 0.6 litres. If their alveolar ventilation rate is 4.8 litres per minute, how many breaths do they take per minute? Show your working.

Answer: Number of breaths = alveolar ventilation / volume per breath = 4.8 L / 0.6 L = 8 breaths per minute.

Question 1: Describe a safe and ethical method to measure a person's lung capacity in a school laboratory setting.

Answer: Use a spirometer with a disposable mouthpiece, ensure proper hygiene, and obtain consent. Have the person breathe normally and then deeply, recording the volume measured.

Question 2: Identify two variables that should be controlled when measuring lung capacity in an experiment and explain why.

Answer: Variables include the person's posture and the temperature of the air, as these can affect lung volume measurements.

Question 1: A group of students recorded their resting tidal volumes, which ranged from 0.4 to 0.6 litres. The average was 0.5 litres. What does this data suggest about normal lung function, and what factors could influence individual differences?

Answer: The data indicates typical resting lung volumes, with individual differences due to age, fitness, body size, or health conditions.

Question 1: Explain how understanding lung structure and function is important for developing treatments for respiratory diseases such as asthma and COPD. Include at least three points in your answer.

Answer: Understanding lung structure helps in designing inhalers that target specific airways, aids in developing drugs to reduce inflammation or mucus production, and informs rehabilitation strategies for patients with compromised lung capacity.

Question 1: Describe how advancements in lung imaging technology, such as CT scans, have improved diagnosis and treatment of lung conditions.

Answer: CT scans provide detailed images of lung structures, allowing for early detection of abnormalities, precise diagnosis, and targeted treatment planning, improving patient outcomes.