26. Increasing density of erythrocytes in blood increases its capacity to carry oxygen. However, the viscosity of the blood increases with hematocrit and the blood flows less easily. One might hypothesize that there is an optimum hematocrit for oxygen carriage. Viscosity does not increases linearly with hematocrit. In one study, for hematocrits of 20, 35, 52, and 62%, viscosities were found to be 1.4, 2.0, 3.0, and 4.0 centipoise (a unit for measuring viscosity). Since flow rates vary inversely with viscosities, the relative rates at which erythrocytes (and the oxygen they carry) flow through blood vessels can be found by dividing the hematocrit values by their respective viscosities. What are these ratios for the four hematocrit values? Is there an optimum erythrocyte concentration for blood flow? How well does it correspond to the typical values for men and women (about 45% and 40% respectively)?

26. Increasing density of erythrocytes in blood increases its capacity to carry oxygen. However, the viscosity of the blood increases with hematocrit and the blood flows less easily. One might hypothesize that there is an optimum hematocrit for oxygen carriage. Viscosity does not increases linearly with hematocrit. In one study, for hematocrits of 20, 35, 52, and 62%, viscosities were found to be 1.4, 2.0, 3.0, and 4.0 centipoise (a unit for measuring viscosity). Since flow rates vary inversely with viscosities, the relative rates at which erythrocytes (and the oxygen they carry) flow through blood vessels can be found by dividing the hematocrit values by their respective viscosities. What are these ratios for the four hematocrit values? Is there an optimum erythrocyte concentration for blood flow? How well does it correspond to the typical values for men and women (about 45% and 40% respectively)?

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter11: The Blood

Section: Chapter Questions

Problem 3SQE

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In a woman with body mass 70 kg blood quantity is 4.9 liters; hematocrit is 32%, the quantity of erythrocytes is 3.0*10^12/l, hemoglobin is 105 g/l color parameter is 1.0, the minimum osmotic resistance of erythrocytes is 0.38%NaCl; the maximum osmotic resistance of erythrocytes is 0.34%NaCl Such blood analises testifies first of all about: A. the water excess in the organism B. the lack of water in the organism C. osmotic hemolysis of erythrocytes D. chemical hemolysis of erythrocytes E. the lack of iron in blood plasma
. Do you think erythropoietin levels in athletes at low altitude are lower, higher, or the same after training at a high altitude for 2 months? Explain your answer. Calculate the average ml of oxygen molecules in 100 ml blood in the athletes at low altitude and then in athletes in high altitude while training at high altitude. Use the following information: 1.39 ml of oxygen per gram of hemoglobin. . Do athletes training at high altitudes have more or less oxygen molecules per ml of blood then athletes training at low altitudes? Explain why this difference gives athletes who train at high altitudes an advantage over athletes who train only at low altitudes.
(b) The diagram on the right illustrates the change in the p50 (partial pressure of O2 required to achieve 50% saturation) of hemoglobin and the 2,3-bis-phosphoglycerate (BPG) concentration in the erythrocytes of a person who spent 6 days hik- ing in the Andes Mountains of Peru. As the hiker climbs to higher and higher altitudes, the atmos- pheric pressure, including the partial pressure of O2, decreases. Yet the p50 increases, making it less favorable to achieve saturation of the hemo- globin. Explain. Pso (torr) Sea level 34 33- 32 31 30- 29 28 27 26 4530 m above- sea level (c) If individuals with the following mutant hemo- globins accompanied the hiker, evaluate the degree of respiratory distress that they would experience despite the increased erythrocyte BPG concentration. (In the ta- ble of mutants on the right, the mutation His(143)Asp, for instance, means that the His residue that occurs at se- quence position 143 on the ß-chain has been substituted by Asp.) Describe the…
o Suppose Gina climbs a high mountain where the oxygen partial pressure in the air decreases to 70 torr. Assume that the pH of her tissues and lungs is 7.4 and the oxygen concentration in her tissues is 20 torr. The P50 of hemoglobin is 26 torr. The degree of cooperativity of hemoglobin (n) is 2.8. Estimate the percentage of the oxygen-carrying capacity that she utilizes. oxygen-carrying capacity utilized: After Gina spends a day at the mountaintop, where the oxygen partial pressure is 70 torr, the concentration of 2,3-bisphosphoglycerate (2,3-BPG) in her red blood cells increases. Why does increasing the concentration of 2,3-BPG in Gina's blood cells help her function well at high altitudes? The P50 value of her hemoglobin increases, promoting oxygen delivery to tissues. The P50 value of her hemoglobin decreases, causing more blood-to-tissue oxygen offloading. The extra 2,3-BPG stabilizes the relaxed, or R, state of hemoglobin, increasing oxygen binding. Excess 2,3-BPG binds oxygen…
1) Calculate how much plasma and blood cells contain in blood of a person if his body mass is 80 kg, hematocrit is 40%. Volume of circulated blood is normal. Estimate the results.
Which of the following are true of normal adult hemoglobin? Choice 1 of 4:can bind four Fe2+ ions Choice 2 of 4:can covalently bind four O2 molecules Choice 3 of 4:can adopt 2 different conformations, with different orientations of αβ dimers Choice 4 of 4:can bind four BPG molecules to stabilize the T state
Table 3: Effect of Altitude on Hct and Hb Low Altitude High Altitude Length of Packed RBC Column (mm) Hb (g/100 ml Length of Whole Blood Column (mm) Length of Packed RBC Column (mm) Hb (g/100 ml Length of Whole Blood Column Hematocrit Hematocrit (mm) (%) blood) (%) blood) 14.5 Subject 1 50 23 46 49 25 51 17.4 Subject 50 21 42 14.5 50 23 46 17.4 Subject 3 51 22 43 14.5 49 25 51 17.4 Average 50 22 44 14.5 49 24 49 17.4 Changes in Blood Hematocrit After 2 Month Acclimatization to High Altitude % 100 90 80 70 60 50 Low altitude 40 30 High altitude 20 10 Hematocrit Changes in Blood Hemoglobin After 2 Month Acclimatization to High Altitude g/100 ml 20 16 12 Low altitude 8 High altitude 4 Hb 1. What are the average hematocrit values (%) at low altitude and then after the subject trained at high altitude for 2 months?
69. During conditions of low oxygen (hypoxia), which of the following will stimulate increase production of red blood cells to cmopensate for low oxygen? iron sulfate erythropoietin thrombopoietin leukopoietin
It is not usually necessary to assess arterial blood gases when diagnosing and treating asthma. However, this information can sometimes be useful in severe asthma attacks. Suppose that a patient had a PO2 of 60mm hg and a PCo2 of 30mm hg when the patient first went to the emergency room. Explain how that could happen.
Table 3: Effect of Altitude on Hct and Hb Low Altitude High Altitude Hb Length of Packed RBC Column (mm) (g/100 ml Length of Whole Blood Column (mm) Length of Packed RBC Column (mm) Hb (g/100 ml blood) Length of Whole Blood Column Hematocrit Hematocrit (mm) (%) blood) (%) Subject 1 50 23 46 14.5 49 25 51 17.4 17.4 Subject 2 50 21 42 14.5 50 23 46 Subject 3 51 22 43 14.5 49 25 51 17.4 Average 50 22 44 14.5 49 24 49 17.4 Changes in Blood Hematocrit After 2 Month Acclimatization to High Altitude % 100 90 80 70 60 50 Low altitude 40 30 High altitude 20 10 Hematocrit Changes in Blood Hemoglobin After 2 Month Acclimatization to High Altitude g/100 ml 20 16 12 8 Low altitude High altitude 4 Hb
In 1913, Archibald Hill described an alternative formulation for cooperative processes such as the binding of oxygen by hemoglobin by considering the hypothetical equilibrium Hb+ n0₂ Hb(0₂)n 2 Analysis leads to the Hill equation: n p02₂" ( Y log (₁ x x ) = log Y (^_^) log where Y is the fractional saturation. This equation suggests that a plot of log with slope n. Plots for myoglobin and hemoglobin are shown here: 3 2 1 O -1 -2 -3 P50 + n = nlog (pO,) – n log(P5o) Myoglobin (0.25, -0.25) -1 0 1 2 log (pO₂) (3.0, 2.5) 3 4 (^_^) log 3 2 1 O -1 -2 -3 -4 (0, -3.4) -1 0 Y Y versus log (pO₂) should yield a line Hemoglobin (2.1, 2.5) - (0.7, -2.0) (1.9, 1.3) (0.4, -3.5) 1 2 log (pO₂) - (2.4, 2.4) 3 4
Calculate the hematocrit of a female patient using the following information:The height of the whole body is 80mm, and the height of the RBC's is 28mm. How is her hematocrit value as compared to the hematocrit normal value of adult femal?