* Gas exchange
* Necessary because cells require oxygen.
* Exchanging O2 and CO2
* Carbon Dioxide is a waste product and must be removed from the body. * Internal respiration = gas exchange at the cellular level. * Oxygen diffuses from the blood into the tissue cells. * External respiration = gas exchange at the alveoli level. * Oxygen from the inhaled air diffuses into the blood in the pulmonary capillaries. * Three primary parts of respiration:
* Ventilation, profusion, diffusion.
* Ventilation = movement of gases into and out of the lung. * Position – dependent areas receive majority of air. * Lung volume – low volume results in shunting air to lung apices. * Disease – bronchial constriction and airway collapse decrease ventilation. * Ventilator mechanically assists patient to breathe.
* Profusion = flow of blood in a specific organ of the body. * Position – dependent areas receive majority of blood. * Hypoxia – results in vasoconstriction and decreased perfusion. * Blockage – results in decreased or absent perfusion to distal areas. * If the heart is not profused enough = heart attack.
* If the brain is not profused enough = stroke.
* Diffusion = movement of gases across the alveoli.
* Oxygen moves from areas of high concentration to areas of low concentration. * Movement of gases occurs at the alveolar capillary membrane. * Alterations occur in thickness and permeability of membrane. 2. Respiratory System
* Respiratory Anatomy and Physiology
* The respiratory system consists of two main parts:
* The upper and the lower tracts.
* Its function is to warm, filter, humidify, inspired air. * Nose is the best place to breathe through (helps filter our microorganisms). * Upper Respiratory System
* Pharynx = throat, back of nose and mouth (oropharynx and nasopharynx). * Larynx = voice box, connects pharynx to trachea.
* Epiglottis = covers larynx during swallowing.
* The Nose
* First part of respiratory system.
* Contains nasal bones and cartilage.
* Has numerous superficial blood vessels in the nasal mucosa. * Function is to: filter air, humidify air, aid in phonation (sound), and olfaction (smell). * Warms air better because of blood supply.
* The Pharynx
* Musculomembranous tube.
* Passageway for both air and food.
* Protect lower airway.
* Nasopharynx and Oropharynx.
* The Larynx
* AKA voice box.
* Made of cartilage and membranes.
* Connects the pharynx to the trachea.
* Functions: vocalization, keeps the patency of the upper airway, and protects the lower airway. * Sometimes has to be removed in people with throat cancer, and must have an artificial set of vocal cords, voice box. * Lower Respiratory System
* Main bronchus
* Bronchial tree
* Lungs = 3 lobes on right, 2 lobes on left.
* The right lung is slightly larger than the left.
* The left lung contains a hollowed-out notch where the heart nestles. * The Trachea
* Made of cartilage.
* Tube measures approximately 10-12 cm. Composed of about 20 C-shaped cartilages. * Function: conduct air towards the lungs, mucosa is lined up with mucus and cilia to trap particles and carry them towards the upper airway. * Ultimately the goal is to have the bacteria go out of the body. * The Bronchus
* The right and left primary bronchi begin at the carina. * Function: air passage.
* Right bronchus is wider, shorter, more vertical.
* Significance: easier for infections and obstruction to happen in right bronchus. * Left bronchus is narrower, longer, more horizontal.