pressure in thee chest cavity during inhalatoin and exhalation
the dome-shaped muscle at the bottom of the chest cavity is the diaphragm
During inhalation, contraction of the diaphragm and rib muscles increases chest
volume and air rushes in.In exhalation, these muscles relax and air rushes out.
the nervous system has final control of the breathing muscles. Breathing
does not require conscious control
Smoking and the Respiratory system chemical in tobacco smoke damage structures throughout the respiratory system
and have other negative health effects. smoking causes a number of diseases, including chronic bronchitis, emphysema, and lung cancer