Slide 1DefinitionsRespiratory System FunctionsDivisions of the Respiratory SystemDivision of the Respiratory SystemUpper Respiratory TractUpper Respiratory SystemNoseNasal CavityParanasal SinusesPharynxPharynx regionsRegions of the PharynxLower Respiratory Tract (Conducting Portion)Lower Respiratory Tract (Respiratory Portion)LarynxMajor Cartilages of the LarynxThyroid CartilageCricoid CartilageEpiglottisSound ProductionSound ProductionTracheaBronchiole TreeBronchial TreeBronchial TreeBronchiolesRespiratory Portion of the Respiratory SystemBronchioles and AlveoliSlide 30Lungs and PleuraLungsLungsSlide 34LungsSlide 36LungsHilumLeft LungSlide 40Right LungRespirationSmokingEmphysemaLung CancerRespiratory SystemDefinitionsRespiratory System – provides the means for gas exchangeRespiratory control is from the diaphragmConsists of air passages and lungs that supply oxygen to the blood for cellular respiration and eliminate carbon dioxideCarbon Dioxide is the waste product by the cellsRespiratory System FunctionsThe main function of the respiratory system is breathing. This involves both inhalation and exhalation. Some of the other functions are:Gas conditioningSound productionOlfactionDefenseDivisions of the Respiratory SystemDivision of the Respiratory SystemAnatomically, the system can be divided into upper and lower respiratory tracts.Functionally, the system can be divided into conducting and respiratory portions.Conduction – transport air (nose, nasal cavity, pharynx, larynx, trachea)Respiratory – within the small parts of the lungsUpper Respiratory TractThe upper respiratory tract is comprised of the following: nose and nasal cavities paranasal sinuses pharynxThese are all part of the conducting portion of the respiratory system.Upper Respiratory SystemFigure 25.2Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.Superior nasal conchaMiddle nasal conchaInferior nasal conchaVestibuleNostrilHard palateTonguePalatine tonsilLingual tonsilEpiglottisLarynxThyroid cartilageCricoid cartilageTracheaFrontal sinusSphenoidal sinusSuperior meatusMiddle meatusInferior meatusChoanaePharyngeal tonsilOpening of auditory tubeSoft palateUvulaNasopharynxOropharynxPharynxLaryngopharynxEsophagusParanasalsinusesNasalcavityOral cavityNasalcavityNoseThe nose is the main conducting airway for inhaled air.It is supported by paired nasal bones superiorly that form the bridge of the nose.Nasal CavityThe nasal septum divides the nasal cavity into right and left portions and forms the medial wall of each cavity.The superior, middle and inferior nasal conchae form the lateral wall for each cavity.The conchae condition the air within the nasal cavity.Warm and humidify airParanasal SinusesFour bones of the skull contain paired air spaces called paranasal sinuses. These spaces make the bones lighter in weight and are named after the bones in which they reside: frontal ethmoidal sphenoidal maxillaryPharynxOne of the few areas of the body that is shared by two organ systems (digestive and respiratory). The pharynx is divided into three regions: nasopharynx oropharynx laryngopharynxThe pharynx is commonly referred to as the throat.Pharynx regionsRegions of the PharynxLower Respiratory Tract(Conducting Portion)The lower respiratory tract is comprised of the following conducting passageways: larynx trachea bronchi bronchiolesLower Respiratory Tract(Respiratory Portion)The lower respiratory tract is comprised of the following structures : respiratory bronchioles alveolar ducts alveoliLarynxConnects pharynx to tracheaAlso called the voice box, houses the vocal cordsSupported by a framework of cartilages, ligaments, and musclesSplits into the trachea and the esophagusThe three major cartilages are:1. Thyroid cartilage2. Cricoid cartilage3. EpiglottisMajor Cartilages of the LarynxFigure 25.4Thyroid CartilageLargest cartilageHas an anterior and lateral wallNo posterior wallV-shaped anterior projection is called the laryngeal prominence (Adam’s apple)Attaches to the lateral sides of the cricoid cartilageUsually larger in males than in females because of testosterone influence on growth of cartilageCricoid CartilageJust inferior to the thyroid cartilageComplete ring-shaped cartilageFigure 25.4EpiglottisSpoon-shaped cartilage that projects superiorly into pharynxSwallowing causes the epiglottis to close the opening to the larynx thus preventing materials from entering the lower respiratory tractSound ProductionVocal folds are found in the larynx and are comprised of vocal ligaments covered by a mucous membrane.When air is forced through the rima glottidis, it causes vibration of the vocal folds, which results in the production of sound.Sound ProductionThe range of a voice is determined by the length and thickness of the vocal folds. Vocal fold increase in length with age, which is why our voices deepen with time. Voice pitch is determined by the amount of tension on the vocal folds.Increased tension=more vibration=higher soundLoudness depends on the force of the air passing across the vocal cords. Lots of air = loud soundLittle sound=soft soundWhisper –vocal cords don’t vibrate, which is why all whispersTracheaInferior to the larynx, superior to the primary bronchi, and anterior to the esophagus2.5 cm in diameter and 12–14 cm in lengthSupported by 15-20 C-shaped tracheal cartilagesLined with mucous to trap inhaled foreign particles which are then lifted upwards towards the larynx and pharynx to be swallowed into the stomachBronchiole TreeThe bronchial tree is a highly branched system of air-conducting passages that begin with the primary bronchi and end with the terminal bronchi.These passages belong to the conducting portion of the respiratory system.They reside within the substance of the lungs.Bronchial TreeFigure 25.8Bronchial TreeThe trachea branches into left and right primary bronchi.The right primary bronchus is wider and more vertical and foreign particles are more likely to get lodged in this bronchus.The right primary bronchus divides into three secondary bronchi.The left primary bronchus divides into two secondary bronchi.The secondary bronchi divide into 8–10 tertiary bronchi (segmental