Make more room
Moving the diaphragm down increases chest volume.
Breathing Model
Move a diaphragm model and observe changes in chest volume and net airflow.
Grades 2–5 · Biology
Your goal
Move the diaphragm so air flows in and reaches diaphragm level 4.
Reduced motion is on. The controls still update the scene.
Diaphragm level 2. Chest air space is 4 model units. The diaphragm is held still. There is no net airflow in this settled model.
During a quiet breath in, the diaphragm contracts and moves down. Chest volume increases and the pressure change draws air into the lungs. Relaxation lets it move up as air leaves. This sectional model shows net airflow during a movement and after settling, not oxygen exchange, breathing rates or medical measurements. Rib muscles and tissue recoil are simplified.
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Learn with Breathing Model
Breathing Model gives elementary students a visual link between diaphragm position and air movement. Move the diaphragm downward to increase the illustrated chest space and draw air into the lungs. Move it upward to reduce that space and move air out. A hold control shows the settled state with no net airflow. Guided goals ask students to produce inward flow, outward flow and a still position while reading the shared volume scale. The activity explains that its model units are illustrative and do not measure breathing health or oxygen exchange.
What to look for
Compare directions
An upward movement reduces space and moves air out.
Try a hold
Hold after moving to observe a settled state with no net airflow.
For teachers and curious learners
Connect diaphragm movement, chest volume and the direction of airflow. Ask students to predict what will happen, change one setting, and explain what they observe. Learn gives a starting point. Practice and Challenge offer new goals with the same scene.
Sectional diaphragm and chest-space illustration. Flow describes net movement during a change and after settling, without rates, gas exchange or medical measurements.