Visceral cartilage.

Visceral cartilage is found in the airways and appendages of the respiratory tract. It has a characteristic arrangement at various airway levels. Cartilage maintains the large airways patent and since muscle attachment is in part to cartilage, its arrangement influences the effect of muscle contraction. Bronchi are defined as the airways proximal to the last plate of cartilage. The intra-uterine development of cartilage, its distribution in the adult, change in disease and the bronchial arterial supply of large airways are considered.