NURS 3628 Sherpath Notes Test 2: Sherpath Notes Test 2 Respiratory System Review.

Respiratory System: • Upper respiratory tract - nose, pharynx, and larynx • Lower respiratory tract - trachea, bronchi, bronchioles, and lungs including alveoli Upper airway • The main function of the upper respiratory system is to filter, warm, and humidify inhaled air. Nose & pharynx: • Air enters the body through the nares or nostrils, two nasal cavities lined with mucous membrane. • Infants are obligate nasal breathers until at least 2 months of age. • Air can also enter through the mouth into the pharynx or throat, but it would not be humidified and filtered as it would be in the nose. • The nasopharynx is located immediately behind the nasal cavity; the oropharynx is located behind the mouth. • The laryngeal pharynx lies below the oropharynx and opens into the larynx toward the front and into the esophagus toward the back. Larynx and Epiglottis • The larynx is located between the pharynx and the trachea. • The vocal cords are at the upper end of the larynx. • The proximity of the upper esophagus to the upper respiratory system can put an individual at risk for inhaling food or liquids (aspiration), but the epiglottis covers the larynx during swallowing and helps keep food out of the lower respiratory tract. • Cilia are microscopic hair-like structures that move mucus and fluid (known as the mucociliary escalator). • Damage to cilia interferes with the removal of mucus from the respiratory tract. 1. Ciliated mucous membranes line the larynx and filter dust and other particles from the air. 2. The particles are then carried to the pharynx to be removed by sneezing, blowing, or coughing. 3. After being filtered, the air that enters the respiratory system is humidified and warmed before proceeding into the lungs.