These are tiny "fingers" which move mucous. The mucous is sticky and traps dust, pollen and other particles. Together the cilia move the mucous out of the lungs. If this didn't happen these things trapped in the mucous would cause damage to the lungs and a person would have breathing difficulties over time.
The combination of cilia and mucous helps to filter out solid particles from the air.
The trachea is lined with ciliated columnar epithelium, which has hundreds of tiny hairs called cilia.
The trachea.
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Cilia are found on the outside of the cell as projections for bacteria and virus.
Mucous membranes and cilia in the trachea trap and eliminate particulate matter from inhaled air. The membranes also warm and moisten incoming air.
In the lining of the trachea, bronchi, and bronchioles.
Cilia.
shijuhew
The hairs on the trachea are called Cilia and are for helping lifting up the mucus up the throat. Smoking can kill these hairs and they will have to swallow the mucus.=D
For a human who has smoked and destroyed the cilia by coating the inner wall of the trachea with tar, the mucus that is secreted will have no mechanism to bring it up the trachea to be swallowed except for the 'smoker's hack', a chronic cough that brings up the phlegm from the lungs. Those cilia do not regenerate so, the person will have the 'smoker's hack' for the rest of his life.
The cilia are always moving, bacteria or particles of dust trapped in the mucus are moved away by cilia. The cilia waft the mucus containing bacteria and dust up to the back of the throat, so that it doesn't block up the trachea and thus keeps it clean.