GCSE PE - Theory
The Respiratory System
p h y s e d
Contents:
physed
Message
Board
Course notes
Sample exam questions
Ask your own questions - physed Message Board
Web links
All files are MS 97 .doc files. Please contact me if you have difficulty opening them.
Course notes
The lungs and breathing
This site is maintained by Sean Bettinson. Send comments to:
The Alveoli
Your lungs take in oxygen and give out carbon dioxide. This gas exchange takes place in the Alveoli in the lungs.
? The alveoli are at the end of a Bronchiole. Each Alveolus id smaller than a grain of salt.
? The walls of the alveoli are thin and moist which helps gasses pass through it.
? The alveoli are covered with tiny blood vessels called capillaries. Gases can pass through the capillary walls.
Gas exchange in the alveoli
Pupils to copy, from overheads, the 5 statements � in order - which correspond to diagram. Also, put arrows and numbers on the diagrams to correspond with the order of the statements below:
1. Blood carries waste carbon dioxide from the body cells to the alveoli.
2. The carbon dioxide passes through the capillary walls and into the alveoli.
3. From here it travels out of the lungs and up the windpipe. You breathe it out.
4. You breathe in oxygen. It passes through the alveoli walls and into the capillaries.
5. The blood carries the oxygen away to the body cells.