NURS 2820U Lecture Notes - Lecture 6: Rhinorrhea, Vascular Resistance, Coronary Artery Disease
Document Summary
The smaller the airway it gets, the greater the proporion of smooth muscle than carilage. As you go deeper, few carilages are present unil the terminal bronchioles (last stop of made up of carilage). Terminal bronchi is the only one made up of smooth muscle. Going further down where presence of only smooth muscle, smooth muscles can change in diameter- efect of physiology and pathophysiology. Ex bronchoconstricion (copd, asthma) and bronchodilaion (periods of exercise) At alveoli, only 1 epithelial layer present for easy difusion of oxygen, nutrients, and wastes from the blood vessel. Prov ide stru ctur e to the alve olar sac. Destrucion leads to less perfusion of pulmonary capillaries. Around single alveolus, muliple capillaries present which carry blood. Type 1 alveolar cell responsible for the structure of the alveolus. When this structure is lost, alveoli walls collapse (happens in copd).
