Study Guide Exam III Pet 3322 Anatomy and Physiology I July 19 2011 Chapter 22 The Respiratory System Functional Anatomy of the Respiratory System The major function of the Respiratory System is to supply the body with oxygen and dispose of carbon dioxide To accomplish this the 4 processes of respiration must occur o 1 Pulmonary ventilation movement of air into and out of the lungs breathing o 2 External respiration movement of oxygen from the lungs to the blood o 3 Transport of respiratory gases transport of ozygen from the lungs to the tissue cells of the body and of carbon dioxide from the tissue cells to the lungs o 4 Internal respiration movement of oxygen from blood to the tissue cells the actual use of oxygen and production of carbon dioxide by tissue cells known as cellular respiration is the cornerstone of all energy producing chemical reactions in the body respiratory zone is the actual site of gas exchange It is compsed of the respiratory bronchioles alveolar ducts and alveoli conducting zone includes all other respiratory passageways which provide fairly rigid conduits for air to reach gas exchange sites o this zones organs also cleanse humidify and warm incoming air 1 List the structures and functions of the nose nasal cavity and paranasal sinuses Also see chart below the nose o provides and airway for respiration o moistens and warms entering air o filters and cleans inspired air o serves as a resonating chamber for speech o houses olfactory smell receptors divided into the external nose and internal nasal cavity o features of external nose root between eyebrows bridge dorsum nasi anterior margin apex tip of nose philtrum shallow vertical groove inferior to apex o 2 Describe the structures of the pharynx larynx and trachea See chart below 3 Explain the structure of the lungs and the vascular and neural networks that supply them See chart below 4 Discuss the relationship of the pleurae to the lungs and thoracic wall and their functional importance See chart below Study Guide Exam III Pet 3322 Anatomy and Physiology I July 19 2011 Structure Nose Description Jutting external portion is supported by bone and cartilage Internal nasal cavity is divided by midline nasal septum and lined with mucosa Function Produces mucus filters warms and mositens incoming air resonance chamber for speech Paranasal sinuses Muscosa lined air filled cavities in Pharynx Layrnx Trachea Bronchial tree Alveoli Roof of nasal cavity contains olfactory epithelium cranial bones surrounding nasal cavity Passageway connecting nasal cavity to layrnx and oral cavity to esophagus Three subdivisions nasopharynx oropharynx and laryngopharynx Houses tonsils lymphoid tissue masses involved in protection against pathogens Connects the pharynx to the trachea Has framework of cartilage and dense connective tissue Opening glottis can be closed by epiglottis or vocal cords Houses vocal folds true vocal cords Flexible tube running from layrnx and diving inferiorly into two main bronchi Walls contain C shaped cartilages that are incomplete posteriorly where connected by trachealis muscle Consists of right and left main bronchi which subdivide within the lungs to form lobar and segmental bronchi and bronchioles Brinchiolar walls lack cartilage but contain a complete layer of smooth muscle Constriction of this muscle impedes expiration Microscopic chambers at termini of bronchial tree Walls of simple squamous epithelium are underlain by thin basement membrane External receptors for sense of smell Same as for nasal cavity Passageway for air and food Facilitates of immune system to inhaled antigens Air passageway prevents food from entering lower respiratory tract Voice production Air passageway warms cleans moistens incoming air Air passageways connecting trachea with alveoli cleans warms moistens incoming air Main sites of gas exchange Study Guide Exam III Pet 3322 Anatomy and Physiology I July 19 2011 surfaces are intimately associated with pulmonary capillaries Special alveolar celss produce surfactant Paired conposite organs that flank mediastatium in thorax Composed primarily of alveoli and respiratory passageways Stroma is fibrous elastic connective tissue allowing lungs to recoil passively during expiration Serous membranes Parietal pleura lines thoracic cavity visceral pleura covers ecternal lung surfaces Reduces surface tension helps prevent lung collapse House respiratory passages smaller than the main bronchi Produce lubricating fluid and compartmentalize lungs Lungs Pleurae Mechanics of Breathing 5 Define intrapulmonary and intrapleural pressure Intrapulmonary pressure Ppul is the pressure in the alveoli o It rises and falls with the phases of breathing but always eventually equalizes with atmospheric pressure Intrapleural Pressure Pip is the pressure in the pleural cavity also fluctuates with breathing phases but always less than the intrapulmonary and atmosphere pressure Two forces act to pull the lungs visceral pleura away from the thorax wall parietal pleura and cause lung collapse o 1 The lungs natural tendancy to recoil lungs always assume the smallest size possible o 2 The surface tension of the alveolar fluid surface tension constantly acts to draw the alveoli to their smallest possible dimensions These lung collapsing forces are opposed by natural elasticity of the chest wall a force that tends to pull the throax outward and to enlarge the lungs Transpulmonary pressure the difference between the intrapulmonary pressure and intrapleural pressures keeps the air space of the lungs from collapsing 6 Describe pulmonary ventilation and the relationships between pressure and volume changes as they apply to the lungs Breathing or pulmonary ventilation consists of two phases o Inspriation o Expiration the period when air flows into the lungs the period when gases exit the lungs Respiratory pressures are always described relative to atmospheric pressure Patm which is the pressure exerted by the air gases surrounding the body Negative respiratory pressure is less than Patm Positive respiratory pressure is more then Patm Zero respiratiry pressure is equal to Patm Study Guide Exam III Pet 3322 Anatomy and Physiology I July 19 2011 Pulmonary Ventilation o A mechanical process that depends on volume changes in the thoracic o Boyle s Law cavity gas At constant temperature the pressure of a gas varies inversely with its volume shows the relationship between pressure and volume of a P1V1 P2V2 P is the pressure
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