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What is the function of the trachea?

1 Answer
Dec 16, 2016


The main function of the trachea is to provide air flow to and from the lungs.


The trachea is a tube about 10 cm long and 20 mm in diameter.

It starts at the larynx and runs to just below the sternum, where it divides into the left and right bronchi of the lungs.


Functions of the trachea

1. Air conduction

The primary function of the trachea is to provide air passage to your lungs for respiration, i.e. to inhale air rich in oxygen and exhale carbon dioxide.

2. Protection

The lining of the trachea has a sticky mucous lining that traps foreign substances.

These trapped substances are expelled upwards and can either be excreted from the body as phlegm or swallowed in the esophagus.

If a foreign object accidentally gets into the trachea, the ciliary cells get irritated and induce coughing to expel the object.

3. Thermoregulation

When the air is cold, the trachea helps to humidify and warm the air entering the lungs.

When the air is hot, heat is carried away in exhaled air through evaporation of water.