The trachea, also known as the windpipe, stays open due to the presence of cartilage rings in its walls.
The trachea, also known as the windpipe, stays open due to the presence of cartilage rings in its walls.
These C-shaped rings of hyaline cartilage provide structural support to the trachea, helping it to maintain its shape and preventing it from collapsing. The cartilage rings are incomplete at the back, where they are joined by a fibrous membrane called the trachealis muscle. This allows the trachea to expand and contract slightly during breathing, while still maintaining its shape and keeping the airway open.
Additionally, the trachea is lined with a mucous membrane that produces mucus to trap particles and bacteria in the air that we breathe. Tiny hair-like structures called cilia on the surface of the cells lining the trachea move in coordinated waves to help move the mucus, and any trapped particles or bacteria, out of the airway and up towards the mouth, where they can be coughed or swallowed. This mechanism helps to keep the airway clear and prevent blockages that could potentially be harmful.