Question 1: Explain the process of gas exchange in the alveoli of the lungs.

Answer: Gas exchange in the alveoli occurs through diffusion, where oxygen from the inhaled air diffuses across the thin alveolar walls into the blood, and carbon dioxide diffuses from the blood into the alveoli to be exhaled.

Question 2: Identify the primary gases involved in human respiration.

Answer: Oxygen (O2) and Carbon Dioxide (CO2).

Question 1: Define 'diffusion' in the context of gas exchange.

Answer: Diffusion is the movement of molecules from an area of higher concentration to an area of lower concentration, occurring across respiratory surfaces.

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

Answer: Alveoli have thin walls and a large surface area, which allows for rapid diffusion of gases. Their close proximity to capillaries ensures efficient transfer of oxygen into the blood and removal of carbon dioxide from the blood.

Question 1: Calculate the volume of oxygen consumed in 10 minutes if a person inhales 500 ml of air per breath, with 21% oxygen, and breathes 12 times per minute. (Use the formula: Volume of oxygen = (Air per breath) x (Fraction of oxygen) x (Breaths per minute) x (Time in minutes)).

Answer: Volume of oxygen = 500 ml x 0.21 x 12 x 10 = 12,600 ml or 12.6 liters.

Question 2: If a person's blood contains 20 mL of oxygen per 100 mL of blood, how much oxygen is present in 1 liter of blood?

Answer: Oxygen = 20 mL/100 mL x 1000 mL = 200 mL.

Question 1: Design a simple experiment to measure the effect of exercise on the rate of breathing. Include the variables you would control and how safety would be maintained.

Answer: Students could measure their resting breathing rate and then after performing a set amount of exercise, compare the new rate. Variables to control include age, time of day, and activity type. Safety measures include warming up before exercise, staying hydrated, and avoiding overexertion.

Question 1: A study recorded the oxygen saturation levels in the blood of 10 individuals at rest and after running for 5 minutes. The data shows an average oxygen saturation of 98% at rest and 92% after running. What can be inferred about gas exchange during exercise?

Answer: During exercise, oxygen saturation decreases slightly because muscles use more oxygen, but the body maintains most oxygen levels through increased breathing rate and heart rate, demonstrating efficient gas exchange.

Question 1: Explain how the structure of alveoli and capillaries work together to optimize gas exchange. Include details about surface area, membrane thickness, and blood flow in your answer.

Answer: Alveoli have a large surface area and thin walls, which allow for rapid diffusion of gases. Capillaries are closely wrapped around alveoli, ensuring a short diffusion path. Blood flow in capillaries maintains a gradient for oxygen to enter the blood and carbon dioxide to leave, making the process highly efficient.

Question 1: How do advancements in respiratory technology, such as artificial lungs or ventilators, rely on the principles of gas exchange?

Answer: They rely on the principles of diffusion across membranes, mimicking natural alveolar-capillary exchange to ensure oxygen delivery and carbon dioxide removal in patients with impaired lung function.