
Biology & Psychology
Why Do We Sigh?
Sighing resets collapsed lung sacs and also functions as an emotional pressure valve. It happens automatically about 12 times an hour even when you feel nothing.
sighingbreathing

Biology & Physiology
Why Do We Cough?
Coughing is a high-speed airway clearance reflex that can expel air at over 500 miles per hour. It protects your lungs from particles, irritants, and infection.
coughreflex