Examine the effects of asthma and chronic bronchitis with this highly detailed cross-section model. Four sections of the bronchus rotate on a hinge pin to reveal the internal appearance of tissue deterioration from normal bronchus and hypersecretion of the mucous gland, to lymphoid aggregations and smooth muscle spasms. Students discover the degree of damage due to chronic respiratory illness or distress. The model depicts in colorful representation all bronchus features including cartilage, mucous glands and plug, spiraling smooth muscles, fibroelastic connective tissue, and epithilial layers. Size: 3 3/4”L x 1 1/2” dia.