GCSE Biology: Lungs, Health and Non-communicable Disease

This material covers two linked parts of the GCSE Biology organisation topic: the human gas exchange system and non-communicable disease. It is written for Key Stage 4 students taking GCSE Biology or Combined Science, and the content is common to the main exam boards (for example, the AQA specification places it under organisation, in the sections on the heart and lungs, health issues, lifestyle and cancer).

The first part follows air from the trachea through the bronchi and bronchioles to the alveoli, and explains why the alveoli are such an efficient exchange surface: a very large surface area, walls one cell thick next to thin capillaries, and a rich blood supply that keeps the concentration gradients of oxygen and carbon dioxide steep. You practise stating the direction in which each gas diffuses and linking every adaptation to the rate of diffusion.

The second part starts from the idea of health as a state of physical and mental well-being and the difference between communicable and non-communicable diseases. It then works through how diseases interact (for example, immune defects making infection more likely, or viruses triggering some cancers), the main risk factors named at GCSE — smoking, alcohol, obesity, carcinogens such as ionising radiation, and smoking or drinking during pregnancy — and the difference between benign and malignant tumours, including how malignant cells spread in the blood to form secondary tumours.

A large share of exam marks in this topic comes from data. Several questions give you short sets of figures, such as lung cancer rates in smokers and non-smokers or the number of people with type 2 diabetes in a town, and ask you to calculate a ratio or a percentage change, describe a trend and decide what the data can and cannot show. A recurring theme is the difference between a correlation and a causal mechanism, and why a third factor can create a link between two variables.

The material offers four ways to work. The quiz has twelve questions with explanations, mixing single-answer and multiple-answer items. The flashcards cover the key vocabulary, from alveolus and carcinogen to correlation and causal mechanism. The printable written sheet has eight longer questions in the style of 4 to 6 mark explain and evaluate answers, including calculations from data given in the question, and can be completed by hand and photographed for feedback. The oral exam lets you talk through the topic with an examiner who asks one question at a time and gives brief feedback at the end.

Use it after learning the topic in class, or as focused revision before a mock: the data questions are a good test of whether you can apply the content rather than simply recall it.

• Describe the path of air to the alveoli and explain how the alveoli are adapted for efficient gas exchange
• State the direction of diffusion of oxygen and carbon dioxide in the lungs
• Distinguish communicable from non-communicable diseases and give examples of how diseases interact
• Link the main risk factors (smoking, alcohol, obesity, carcinogens, pregnancy) to their effects
• Explain the difference between benign and malignant tumours and how secondary tumours form
• Interpret health data, calculate ratios and percentage changes, and distinguish correlation from causation

Practice material written by Zestly, based on the DfE GCSE biology subject content (organisation: the lungs; health and non-communicable disease; cancer) and the corresponding exam-board specification content (for example, AQA GCSE Biology 8461 and Combined Science 8464). All data in the questions are illustrative.