Brainlag PlusThe path of air into the lungs, how alveoli are adapted for gas exchange, Fick's law (Edexcel, Biology only), and working with breathing data.
Into the lungs
Air goes down the trachea (held open by rings of cartilage), into two bronchi, then smaller bronchioles, and ends in millions of tiny air sacs, the alveoli.
Each alveolus is wrapped in capillaries.
Oxygen diffuses from the air in the alveoli into the blood; carbon dioxide diffuses from the blood into the alveoli and is breathed out.
The rest of this lesson and its 13 practice questions are in Plus.
Screen 1 of 5, free to read.
- 13 exam-style questions, marked as you go, each with a worked solution
- Anything you get wrong is saved to your flashcards