The Effects of Lung Disease (AQA A Level Biology): Revision Note
Exam code: 7402
The effects of lung disease
There are several conditions that can reduce lung function, e.g. by affecting the structure of the alveolar walls and/or damaging the airways
Examples of lung diseases that affect gas exchange include:
lung cancer
Tumours develop in the lungs due to uncontrolled cell division
The tumour may interfere with the normal working of the lungs, e.g. by squeezing against blood vessels or blocking airways
COPD
Chronic obstructive pulmonary disease (COPD) includes a range of conditions, such as chronic bronchitis and emphysema
COPD causes damage to the lungs or airways, reducing air flow and/or the rate of gas exchange
Examiner Tips and Tricks
Note that you are not required to learn details of different types of lung disease; an exam question will provide any relevant information about a lung disease and expect you to apply your knowledge of the gas exchange system to explain disease symptoms.
Worked Example
The image below compares the alveoli tissue of a healthy individual with that of of a patient with emphysema. Patients with emphysema suffer from symptoms such as shortness of breath and fatigue.
With reference to the image provided, explain the symptoms of emphysema patients.
[3]
Answer:
Emphysema patients have fewer alveoli / larger alveoli SO they have a reduced lung surface area; [1 mark]
The rate of diffusion taking place will be reduced SO less oxygen will enter the blood (causing breathlessness); [1 mark]
There will be a reduced rate of respiration SO less energy will be released (causing fatigue); [1 mark]
You've read 0 of your 5 free revision notes this week
Unlock more, it's free!
Did this page help you?
