Changes

==Structure==

==Structure==

*The trachea contains numerous rings of [[Bones and Cartilage - Anatomy & Physiology#Hyaline Cartilage|hyaline cartilage]] which are C-shaped, being dorsally incomplete, connected to eachother by elastic connective tissue. The ends of the incomplete rings are joined by smooth muscle - ''Trachealis'' muscle.

*The trachea contains numerous rings of [[Bones and Cartilage - Anatomy & Physiology#Hyaline Cartilage|hyaline cartilage]] which are C-shaped, being dorsally incomplete, connected to each other by elastic connective tissue. The ends of the incomplete rings are joined by smooth muscle - ''Trachealis'' muscle.

**The structural conformation of the trachea prevents collapse due to traction forces, whilst allowing it to adjust in length and diameter as the neck moves and the [[Diaphragm - Anatomy & Physiology|diaphragm]] contracts.  

**The structural conformation of the trachea prevents collapse due to traction forces, whilst allowing it to adjust in length and diameter as the neck moves and the [[Diaphragm - Anatomy & Physiology|diaphragm]] contracts.  

*The trachea's walls are made up of a number of layers: Inner Mucosa, Fibrocartilaginous middle layer, and adventitia (in the neck) or serosa (in the thorax).

*The trachea's walls are made up of a number of layers: Inner Mucosa, Fibrocartilaginous middle layer, and adventitia (in the neck) or serosa (in the thorax).