What is the function of trachea?

Answer 1

The trachea is more commonly known as the windpipe.

It is the airway through which respiratory air passes in organisms

Helps with air flow.
The Trachea, more commonly known to be the Wind pipe basically serves as a pathway to your lungs. The air we breath passes through here and to the lungs for oxygenation.
The trachea is what is also known as the windpipe. When you 'suck down air', the oxygen takes the path down the trachea, then the bronchi, then the bronchioles, and the alveoli. When you touch your throat and feel the bumps going down your neck, that is your Trachea. yay! So it contains the air as it goes into the lungs.
The trachea is part of you resportory system and is used to breathe to get air into your lungs

It is just a fancy way of saying yo windpipe!
It provides part of the open passageway through which air can reach the lungs from the outside
the trachea is the tube that connects your mouth to your lungs. It is also known as your windpipe. You can feel it if you touch the front of your throat. It looks similar to a vaccum cleaner hose in that it has ridges. These ridges keep the shape of the thrachea as you breath since there is air moving in and out of it.
oxygen comes in through this tube called the trachea and carbon monoxide expires though this tube also. Without this tube, humans and other animals wouldn't be able to breathe(inspire and expire).

Answer 2

Trachea traps germs and other materials from the air. It also sweeps the dust and dirt upward and away from lungs.