You don't suck air in — you make room for it. The diaphragm changes the chest's volume, which changes its pressure (Boyle's law), and air follows. Watch it breathe.
Inhalation
Breathing mechanicsvolume drives pressure
Thoracic volume
Lung pressure
📷 Reference image
A real labeled figure to compare with the interactive above.
Breathing Mechanics — OpenStax, CC BY 4.0 (via Wikimedia Commons)
