The body’s trillions of cells require an uninterrupted supply of oxygen to release the energy they need to
stay alive. They get this by means of a process called respiration. Air containing oxygen is breathed into
the body by the respiratory system. Oxygen
enters the bloodstream through the lungs and
RESPIRATIONis carried to body cells. Waste carbon dioxide is carried by the blood to the lungs and breathed out.(^70) RESPIRATORY SYSTEMLocated in the head, neck, and chest, the respiratory system consists of the lungs, which fill most of the chest, and the air passages – nasal cavity, throat, larynx, trachea, and bronchi – that carry air. This
X-ray shows the parts of the respiratory system located in the chest.
Muscles between the ribs move the ribcage, which helps to pull air
into the lungs
The right bronchus
branches from the trachea
and divides repeatedly
inside the right lung
The trachea carries air to and from the lungs
Twelve pairs of ribs form the ribcage, which protects the lungs and aids breathing
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