Science
The Human Body
Conceptual
9–11 yrs
How the Lungs Work
肺部的工作原理
Description
Explain how the respiratory system works in detail: air travels through the nose/mouth, down the trachea, into bronchi and bronchioles, reaching tiny air sacs (alveoli) in the lungs where oxygen passes into the blood and carbon dioxide passes out
Mastery Evidence
- Trace the air pathway: nose/mouth → trachea → bronchi → bronchioles → alveoli
- Explain gas exchange in the alveoli: oxygen passes into blood capillaries, carbon dioxide passes out
- Describe the mechanical process: the diaphragm contracts to pull air in and relaxes to push air out
Assessment Prompt
Can your child describe what happens to the air they breathe in — how it travels deeper and deeper into the lungs until oxygen swaps into the blood?
