The Human Gas Exchange System and Breathing - KS3 Biology Worksheet

A complete, no-prep 100-mark worksheet on the human gas exchange system and breathing — ready to use for lessons, homework, or revision with KS3 Biology students aged 11-14. 🫁

The gas exchange system is the group of organs that work together so you can breathe. It is also called the respiratory system.

📝 Structured across three sections of progressive difficulty: Section 1 (30 marks) covers key facts through five multiple choice questions, a ten-statement true or false table and a ten-gap word bank summary of breathing in and out. Section 2 (40 marks) builds understanding through key term definitions, a table on the airways and breathing muscles, and written explanations of air pressure, a squeezed plastic bottle and why the lungs cannot pull air in. Section 3 (30 marks) challenges students with extended answers on breathing out, evaluating the bell jar model and correcting the idea that lungs suck air in. A full answer key with detailed marking guidance is included. Comes as a PDF and an editable Word file (DOCX).

🖥️ Full lesson page with the video, quiz and free worksheet: https://inewittall.com/ks3-biology/the-human-gas-exchange-system-and-breathing/?utm_source=payhip&utm_medium=listing

▶️ Watch the full lesson on YouTube: https://youtu.be/tj1iZkWPUW8

⭐ Also available: a companion extension pack with four enrichment activities, or save £1 with the complete lesson bundle.

KS3 Biology

KS3 Science

worksheet

100 marks

answer key

gas exchange system

respiratory system

breathing

diaphragm

intercostal muscles

air pressure

bell jar model