Study Guide-Exam IIIPet 3322 - Anatomy and Physiology IJuly 19, 2011Chapter 22: The Respiratory SystemFunctional 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 occuro 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 bloodo 3. Transport of respiratory gases: transport of ozygen from the lungs to thetissue cells of the body, and of carbon dioxide from the tissue cells to the lungso 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 siteso this zones organs also cleanse, humidify, and warm incoming air1. List the structures and functions of the nose, nasal cavity, and paranasal sinuses. (Also, see chart below)- the nose:o provides and airway for respirationo moistens and warms entering airo filters and cleans inspired airo serves as a resonating chamber for speecho houses olfactory smell receptors- divided into the external nose and internal nasal cavityo features of external nose: root (between eyebrows) bridge dorsum nasi (anterior margin) apex (tip of nose) philtrum (shallow vertical groove inferior to apex)o2. 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 IIIPet 3322 - Anatomy and Physiology IJuly 19, 2011Structure Description FunctionNose --Jutting external portion is supported by bone and cartilage. Internal nasal cavity is divided by midline nasal septum and lined with mucosa--Roof of nasal cavity contains olfactory epithelium--Produces mucus; filters, warms, and mositens incoming air, resonance chamber for speech --receptors for sense of smellParanasal sinuses Muscosa lined, air-filled cavities in cranial bones surrounding nasal cavitySame as for nasal cavityPharynx --Passageway connecting nasal cavityto layrnx and oral cavity to esophagus. Three subdivisions: nasopharynx, oropharynx, and laryngopharynx--Houses tonsils (lymphoid tissue masses involved in protection againstpathogens--Passageway for air and food--Facilitates of immune system to inhaled antigensLayrnx --Connects the pharynx to the trachea.Has framework of cartilage and denseconnective tissue. Opening (glottis) can be closed by epiglottis or vocal cords--Houses vocal folds(true vocal cords)--Air passageway;prevents food from entering lower respiratory tract--Voice productionTrachea Flexible tube running from layrnx anddiving inferiorly into two main bronchi. Walls contain C-shaped cartilages that are incomplete posteriorly where connected by trachealis muscleAir passageway; warms, cleans, moistens incoming airBronchial tree 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 expirationAir passageways connectingtrachea with alveoli; cleans warms, moistens incoming airAlveoli --Microscopic chambers at termini of bronchial tree. Walls of simple squamous epithelium are underlain bythin basement membrane. External --Main sites of gas exchangeStudy Guide-Exam IIIPet 3322 - Anatomy and Physiology IJuly 19, 2011surfaces are intimately associated with pulmonary capillaries--Special alveolar celss produce surfactant--Reduces surface tension; helps prevent lung collapseLungs Paired conposite organs that flank mediastatium in thorax. Composed primarily of alveoli and respiratory passageways. Stroma is fibrous elasticconnective tissue, allowing lungs to recoil passively during expirationHouse respiratory passages smaller than the main bronchiPleurae Serous membranes; Parietal pleura lines thoracic cavity; visceral pleura covers ecternal lung surfacesProduce lubricating fluid and compartmentalize lungsMechanics of Breathing 5. Define intrapulmonary and intrapleural pressure.- Intrapulmonary pressure (Ppul) is the pressure in the alveolio 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 possibleo 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 collapsing6. 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 – the period when air flows into the lungso Expiration – 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 PatmStudy Guide-Exam IIIPet 3322 - Anatomy and Physiology IJuly 19, 2011-Pulmonary Ventilationo A mechanical process that depends on volume changes in the thoracic cavityo Boyle’s
View Full Document
Unlocking...