Exam 2 Study Guide Answers:1. What is the principle function of the lung: Gas Exchange2. By what process do O2 and CO2 move between the air and blood within the lung? Diffusion3. Explain how the primary design features of the lung facilitate high rates of gas exchange (Use Fick’s Law): The mammilian lung is designed to maximize surface area while minimizing thickness. It does so by having several million small diameter sacs called alveioli.4. What are the two zones of the lung and in which one does gas reside: Respiratory zone and conducting zone. The most gas resides in the respiratory and transition zones. 5. How many bifurcations are found in the human lung: 23 generations, 24 splits6. Draw a graph depicting the relationship between airway generation and total airway cross sectional generation.7. What are the 3 cell types found in alveoli and what are their functions: Type I (Squamous Alveolar) cells that form the structure of alveolar wall, Type II (Great Alveolar) cells that secretesurfactant to lower the surface tension of water and allow the membrane to separate increasing the capability to gas exchanges, Macrophages that destroy foreign material.8. What are the two main forms of connective tissue found in the lungs: Elastin and collagen9. Give Reasonable values for the following: tidal volume(500 ml) respiratory frequency(15/min) alveolar gas volume(3000 ml) dead space volume(150 ml) pulmonary capillary blood volume(70ml) pulmonary blood flow(5000 ml/min)10. Define: functional residual capacity: The amount of air remaining in the lung after a normal expiration.*Important b/c it’s the amount of air available for gas exchange between breaths.Residual Volume: volume of air in the lungs after maximal expiration. Prevents lung collapse.Total Lung Capacity: The maximum amount of air that can be exchanged in a single breath. 11. Explain why it is more efficient to breathe more deeply (increase tidal volume) than increase breathing frequency: Rapid shallow breathing doesn’t as effectively increase useful alveolar ventilation as deeper slower breathing frequencies b/c it wastes too much air in the dead space.12. Where in the lung does the most inspired air go and why?: The Base; Gravity13. What are the principle muscles of: Inspiration- Diaphragm-external intercostals, sternomastoids, scalenes Expiration: Abdominals-internal intercostals14. What is the only respiratory muscle active at rest? Diaphragm 15. Define Lung Compliance: Ability of the lungs to expand change of volume/change in pressure.16. What 3 Factors are important in determining lung compliance and elasticity: Structural propertiesof elastin, collagen, surface tension interdependence17. What happens to the respiratory system when some knucklehead sticks a knife into the pleural space? the lung recoils to its deflated volume which is substantially below residual volume, while the chest wall springs out. - recoils the lung18. What relationship determines the shape of the expiratory flow volume and how is this affected byemphysema and fibrosis: Healthy lungs lung recoil aka alveolar pressure and the size of the airways= effort- independeince * emphysema- increases lung recoil and decreases airway resistance. Airways don’t stay open very long. *fibrosis-increases lung recoil and decreases airway resistance. Can’t open airways very big.19. Why is the pressure of O2 in the alveolar space 100mmHg: Water vapor-dilutes Mixing with CO2 and O2. Dilution of CO2>CO2 stays in the body more than O2, PAO2=PIO2-(PaCO2/R)20. At a pressure of 100 mmHg how much O2 can be carried in the arterial blood: 19.8 ml (O2 ml/100ml = ([Hb] x 1.34 x 0.97) + (PO2 x 0.003)21. Within a closed volume, what happens to pressure if that volume Is reduced to one third and temperature remains constant: If a volume decreases by one third then the pressure increases 3x | P1V1 = P2V222. What are the value for arterial and venous PO2 and PCO2 at rest?: Arterial PO2 = 100 mmHg | Venous PO2 = 40 mmHg | Arterial PCO2 = 40 mmHg | VenousPCO2 = 46 mmHg23. Draw a Graph Depicting the change in PO2 of a red blood cell as it traverses the pulmonary capillary.24. Learn what happens to ventilation, VO2, VCO2, cardiac output (Q), blood lactate and arterial blood gases in response to incremental exercise. Practice Drawing responses25. Learn what happens to ventilation, VO2 and blood lactate response to constant-exercise. Practice drawing the