Anatomy Of Back Muscles The bronchi stem from the trachea performing as openings for atmosphere into the lungs. The kept bronchus is about 5cm lengthy and narrow, whereas the proper is 2 . 5cm very long and wider. The bronchi (more cartilaginous in structure) further expand and part off into bronchioles (which are less cartilaginous and more sleek muscle and epithelial). Typically the bronchioles further lead onto the end of the lower respiratory system where the gaseous exchange may take place.
Further down often the bronchioles, ciliated epithelium are usually replaced with non-ciliated epithelium as well as mucus secreting goblet tissues disappear. The respiratory features of the bronchioles are to control the control of air access (through contraction or leisure of smooth muscle from the walls), and provide warming and also humidifying to the air.