Activity Number 8 for Undergraduate Exercise Phyiology Please complete the following and send it to me at my Sundance account.

1. The partial pressure of a gas (oxygen): A. Undergoes a relative decrease as it approaches the alveoli; B. Remains unchanged as it passes from the environment to the lungs; C. Is equal to its concentration times its amount; D. Is equal to the barometric pressure.

 

 

2. Carbon monoxide, from cigarette smoke, has an affinity for hemoglobin which is far greater than oxygen. A. True; B. False.

 

 

3. The quantity of oxygen combined with blood is dependent upon: A. The amount of Hgb available; B. The partial pressure of oxygen; C. The pressure gradient between the lungs and blood; D. All of the above.

 

 

4. Unlike oxygen, carbon dioxide is carried only in physical solution in the blood. A. True; B. False.

 

 

5. An anemic athlete can still have hemoglobin that is normally saturated. A. True; B. False.

 

 

6. During exercise the oxygen carrying capacity of a gram of hemoglobin increases. A. True; B. False.

 

 

7. Breathing pure oxygen (at sea level): A. During exercise may slightly aid endurance performance by forcing more on to the hemoglobin molecule; B. Slightly aids recovery from exercise by forcing more on to the hemoglobin molecule; C. During exercise has no effect on endurance performance; D. During exercise may slightly aid endurance performance by forcing (dissolving) more into plasma.

 

 

8. Gas exchange at the tissue level (through the tissue-capillary membrane) takes place through osmosis. A. True; B. False.

 

 

9. For a subject living at sea level, the following information is available. Hemoglobin concentration is 14 g·100/mL-1 of blood. The blood is 95% saturated. Which of the following values best describes the oxygen content of arterial blood? Defend your answer by showing your work. A. 20.1 mL O2·100 mL; B. 17.8 mL O2·100 mL; C. 16.4 mL O2·100 mL; D 15.6 mL O2·100 mL.

 

 

10. As it is transported from the lungs toward body tissues (muscle) the blood becomes less saturated with oxygen. A. True; B. False.

 

 

11. At rest, the venous blood is about 70 to 75 percent saturated with oxygen. A. True; B. False.

 

 

12. The most important factor determining gas exchange is the partial pressure gradients of the gases involved. A. True; B. False.

 

 

13. During exercise, there are increases in blood acidity, temperature, and CO2. How do these factors affect the oxyhemoglobin dissociation curve?

 

 

14. The PO2 in blood leaving the alveoli is normally greater than when it leaves the tissue (muscle). A. True; B. False.

 

 

15. Hemoglobin serves as a buffer when hydrogen ions are formed in metabolism. A. True; B. False.

 

 

16. The exchange of gases between alveolar air and blood is due to: A. Active secretion; B. Diffusion; C. Osmotic pressure; D. Selective secretion; E. None of these.

 

 

17. In the mid range of the oxyhemoglobin dissociation curve a relatively small decrease in the PO2 results in a relatively large decrease in percent saturation. A. True; B. False.

 

 

18. Hematocrit: A. Increases blood viscosity (resistance to flow) when elevated; B. Is normally higher in females than males; C. Is reduced during anemia; D. A and B; E. A and C

 

 

19. What is the physiological significance of dissolved oxygen and carbon dioxide?

 

 

20. The oxygen carrying capacity of Hgb is: A. 12 L·min-1; B. 1.34 mL·gm-1 of Hgb; C. Not known; D. None of the above.

 

 

21. As one moves from sea level to modest altitude (4300 m): A. Barometric pressure is reduced thus decreasing oxygen concentration in atmospheric air; B. Barometric pressure is reduced thus decreasing alveolar PO2; C. The affinity of hemoglobin for oxygen is increased; D. A and ; E. B and C.

 

 

22. The oxygen dissociation curve is a graph which illustrates: A. The association of Hgb and CO2 at different oxygen tensions; B. The percent saturation of the Hgb under different oxygen tensions; C. An increase in Hgb association with oxygen under low oxygen tensions; D. A decrease in Hgb association with oxygen under high oxygen tensions.

 

 

23. With hemoconcentration, the oxygen carrying capacity of blood decreases. A. True; B. False.

 

 

24. Hematocrit is: A. A percentage value that represents stroke volume divided by end diastolic volume; B. A whole number that represents red cell mass; C. A percentage that represents red cell mass divided by total blood volume; D. Not a significant factor when discussing blood flow.

 

 

25. Mixed venous blood has an oxygen partial pressure of about 100 mm Hg. A. True; B. False.

 

 

26. The highest PCO2 in the body is found in the: A. Capillar; B. Lung; C. Cell; D. Aorta; E. Inferior vena cava.

 

 

27. The normal hemoglobin concentration in blood is 45 percent. A. True; B. False.

 

 

28. The oxygen dissociation curve is affected by: A. Body temperature and pH; B. Body temperature, pH, and PCO2; C. Only by PCO2; D. By the concentration of red blood cells.

 

 

29. Based upon what you know about the oxyhemoglobin dissociation curve, administering 100% oxygen at sea level is: A. Of little or no value in enhancing performance no matter when it is given; B. Of great value if the athlete could breath it conveniently while competing; C. Of value during the latter stages of recovery; D. Of value before competition, helping the body store significant quantities of oxygen.

 

 

30. Normal saturation of arterial blood is about 98 percent. A. True; B. False.

 

 

31. The highest PO2 in the body is found in the: A. Aorta; B. Arteriole; C. Pulmonary artery; D. A and B; E. A and C.

 

 

32. Oxygen is transported to the body's tissues by: A. Chemical carriers driving oxygen across the membrane; B. Loose chemical combination with Hgb; C. The action of CO2 on the Hering-Breuer Reflex; D. All of these.

 

 

33. Compared with the chemical combination of oxygen with hemoglobin, large quantities of oxygen are carried in physical solution in the blood. A. True; B. False.

 

 

34. Of the various sport related anemias, which one is truly associated with an impairment of maximal exercise performance? A. Iron deficiency anemia; B. False anemia; C. Pseudoanemia; D. Dilutional anemia.

 

 

35. The relationship between oxygen content and oxygen carrying capacity of arterial blood is called: A. The percent saturation of arterial blood; B. The partial pressure of oxygen; C. The partial saturation; D. The pressure of partial saturation.

 

 

36. Explain the significance of the oxyhemoglobin dissociation curve with respect to gas exchange and transport.

 

 

37. At the upper portion of the oxyhemoglobin dissociation curve, a small increase in the partial pressure of O2 results in a large increase in saturation. A. True; B. False.

 

 

38. Explain how cigarette smoking can reduce the O2-carrying capacity of the blood.

 

 

39. The buffering process(es) of the body for carbon dioxide are: A. Small quantities are dissolved in blood plasma; B. Direct association with the hemoglobin molecule forming carbaminohemoglobin; C. Reacts with the bicarbonate ion to form carbonic anhydrase; D. A and B; E. B and C.

 

 

40. Expressed as a percentage, the portion of the blood composed primarily of red blood cells is called? A. Hemoglobin; B. Hematocrit; C. Hemoconcentration; D. Vol %.

 

 

41. The relationship between PO2 and percent saturation on the oxyhemoglobin dissociation curve is a straight line (linear). A. True; B. False.

 

 

42. CO2 may be transported to the lungs as a carbamino compound identified as carbaminohemoglobin. A. True; B. False.

 

 

43. Exercise induced hemoconcentration leads to an apparent increased concentration of hemoglobin. A. True; B. False.

 

 

44. A lowered venous blood PO2 generally indicates greater oxygen uptake in the muscle tissue. A. True; B. False.

 

 

45. Each gram of hemoglobin can transport 1.34 ml of oxygen. A. True; B. False.

 

 

46. Describe the ways in which CO2 is transported from muscle tissue to the lungs.