2024 AQA A-LEVEL BIOLOGY GAS
EXCHANGE EXAM QUESTIONS
WITH CORRECT ANSWERS
Describe changes to the diaphragm upon inspiration. (2) - CORRECT-
ANSWERS- Diaphragm contracts
- And flattens
Explain how the diaphragm causes air to move into the lungs. (3) -
CORRECT-ANSWERS- Diaphragm contracts and flattens
- Increases the volume of the thorax
- Air moves down a pressure gradient and into the lungs
The diaphragm helps to bring abou the increase in the total volume of air
breathed out. Explain how. (3) - CORRECT-ANSWERS- Diaphragm relaxes
- Diaphragm domes
- Volume of the thorax decreases
Curve A could be used to find the total volume of air that this person could
breathe out in one complete breath. Describe how. (2) - CORRECT-ANSWERS-
Extrapolate/ extend the curve
- Read off where curve flattens
Destruction of pahgocytes causes the lungs ti be more suspectible to
infections. Explain why. (2) - CORRECT-ANSWERS- Phagocytes engulf and
destroy pathogens
- Lung infections are caused by inhaling phagocytes/fibres
The reduced elasticity of the lungs causes breathing difficulty. Explain how.
(2) - CORRECT-ANSWERS- MORE residual air in the lungs as they don't
deflate as much upon expiration
- Reduces OXYGEN concentration between the lungs and the environment
- Reduces rate of OXYGEN diffusion into the blood
Apart from reduced elasticity, explain how changes to the lung tissue reduce
the effiency of gas exchange. (4) - CORRECT-ANSWERS- Alevolar walls
thicken
- Longer diffusion pathway for gas exchange
- Scarred tissue
- Decreases surface area for gas exchange
EXCHANGE EXAM QUESTIONS
WITH CORRECT ANSWERS
Describe changes to the diaphragm upon inspiration. (2) - CORRECT-
ANSWERS- Diaphragm contracts
- And flattens
Explain how the diaphragm causes air to move into the lungs. (3) -
CORRECT-ANSWERS- Diaphragm contracts and flattens
- Increases the volume of the thorax
- Air moves down a pressure gradient and into the lungs
The diaphragm helps to bring abou the increase in the total volume of air
breathed out. Explain how. (3) - CORRECT-ANSWERS- Diaphragm relaxes
- Diaphragm domes
- Volume of the thorax decreases
Curve A could be used to find the total volume of air that this person could
breathe out in one complete breath. Describe how. (2) - CORRECT-ANSWERS-
Extrapolate/ extend the curve
- Read off where curve flattens
Destruction of pahgocytes causes the lungs ti be more suspectible to
infections. Explain why. (2) - CORRECT-ANSWERS- Phagocytes engulf and
destroy pathogens
- Lung infections are caused by inhaling phagocytes/fibres
The reduced elasticity of the lungs causes breathing difficulty. Explain how.
(2) - CORRECT-ANSWERS- MORE residual air in the lungs as they don't
deflate as much upon expiration
- Reduces OXYGEN concentration between the lungs and the environment
- Reduces rate of OXYGEN diffusion into the blood
Apart from reduced elasticity, explain how changes to the lung tissue reduce
the effiency of gas exchange. (4) - CORRECT-ANSWERS- Alevolar walls
thicken
- Longer diffusion pathway for gas exchange
- Scarred tissue
- Decreases surface area for gas exchange
