Final Physiology Exam

Questions 1-30 choose the best answer.

For question 1

The following table shows changes in the GFR and in the filtration fraction (FF) in various conditions.

1. Which of the column summarizes the changes in GFR and FF that occur with increased afferent arteriolar resistance?

A. A
B. B
C. C
D. D
E. E

2. Which of the following statements that refers to the glomerulus is correct?

A. It filters Na+ mainly by diffusion
B. It contains no active transport systems that produce an important effect on the composition of filtrate.
C. It produces a filtrate with a lower concentration of amino acids than found in the plasma
D. It produces a filtrate with a higher concentration of urea than found in plasma
E. It does not contain fenestrated capillaries.
F. More that one of the above is true.
G. None of the above are true.

3. A patient is inadvertently given 2 L of isotonic saline over a 4 hour period of time. This infusion should cause an increase in

A. ADH
B. plasma osmotic pressure
C. angiotensin II
D. atrial natriuretic peptide (factor)
E. aldosterone
F. none of the above mentioned will increase

4. A patient with restrictive lung disease typically has

A. an increased forced expiratory volume in 1 second (FEV1) and a normal lung compliance.
B. a decreased FEV1 and an increased lung compliance
C. a decreased FEV1 and a decreased lung compliance
D. an increased FEV1 and an increased lung compliance
E. an increased FEV1 and a decreased lung compliance

5. The vital capacity is the sum of the

A. residual volume, tidal volume and expiratory reserve volume
B. residual volume, tidal volume and inspiratory reserve volume
C. residual volume, expiratory reserve volume and inspiratory reserve volume
D. expiratory reserve volume, inspiratory reserve volume and tidal volume
E. functional residual capacity and inspiratory capacity
F. none of the above are true

6. Which one of the following statements regarding the PCO2 in mixed expired gas is true?

A. It is greater than the alveolar PCO2
B. It is less than the alveolar PCO2
C. It is equal to the alveolar PCO2
D. It is equal to the atmospheric PCO2
E. It is greater than the PCO2 in venous blood
F. None of the above are true

For questions 7 and 8

The blood pressure falls during a surgical procedure on an anesthetized animal. The arterial blood becomes cyanotic despite the maintenance of normal ventilation. The arterial pH is 7.25, and the arterial CO2 tension is 40 mmHg.

7. The acid-base status of the animal is most likely to be

A. metabolic acidosis with respiratory compensation
B. respiratory acidosis with metabolic compensation
C. metabolic acidosis
D. respiratory acidosis
E. respiratory alkalosis with renal compensation

8. To increase pH toward normal, in which direction would the ventilation rate be changed and what would be the corresponding change in arterial CO2 tension.

A. ventilation rate increased; arterial PCO2 increased
B. ventilation rate increased; arterial PCO2 decreased
C. ventilation rate decreased; arterial PCO2 increased
D. ventilation rate decreased; arterial PCO2 decreased
E. ventilation rate increased; arterial PCO2 no change

9. Which of the following statements regarding the normal alveolar CO2 tension is true?

A. It is equal in all alveoli
B. It is highest at the base of vertical lungs
C. It is directly proportional to the inspired O2 tension
D. It is directly proportional to the alveolar ventilation
E. It is equal to 46 mmHg
F. None of the above are true

10. The diffusion coefficient of O2, as compared with that of CO2, is

A. greater because O2 combines with hemoglobin
B. less because O2 is less soluble
C. greater because of a higher pressure gradient
D. less because of the lower molecular weight of O2
E. essentially the same
F. none of the above are true

11. Assuming that the extracellular concentration of sodium is 10 times that intracellular concentration, the equilibrium potential of sodium would be the same as the equilibrium potential for calcium if the extracellular concentration of calcium was

A. 2 times the intracellular concentration of calcium
B. 10 times the intracellular concentration of calcium
C. 20 times the intracellular concentration of calcium
D. 100 times the intracellular concentration of calcium
E. the same as the intracellular concentration of calcium
F. none of the above is correct

12. A middle aged lady came into the emergency room. She says she got hooked on Nickelodeon's 72 hour Brady Bunch Marathon, because she is secretly in love with Mr. Brady and forgot to eat or drink any water for 3 days during the broadcast. She complains of being dizzy.

You run a blood test and finds the following:

plasma osmolarity: 310 mOsm
plasma volume: 1.1L
hematocrit: 55%

You want to rehydrate her with 100 mM solution of glucose. What volume do you give to bring plasma osmolarity back to normal? Assume no fluid diffusion into interstitial tissue.

A. 1 L
B. 1.5 L
C. 1.8 L
D. 2.0 L
E. none of the above answers are within 100 ml of the correct answer

13. A cell has the following electrolyte concentrations: K+ : 85 mM; Na+ : 2 mM; Cl- : 2 mM; Mg+2: 55 mEq. The ECF concentration of these ions are K+ : 4 mM; Na+ : 150 mM; Cl- : 100 mM; Mg+2: 1 mEq. The conductance of these ions are K+ : 20 mmho; Na+ : 2 mmho; Cl- : 1 mmho; Mg+2: 0.5 mmho. The theoretical resting membrane potential for this cell is

A. -75 mV
B. - 65 mV
C. - 70 mV
D. - 80 mV
E. none of the above answers are within 5 mV of the correct answer

14. You have measured the amperage of sodium to be 0.5 mAmps when the membrane potential is -55 mV. The Nernst value for sodium is 60 mV. Calculate the sodium conductance in mmhos. Ignore the sign in the answer.

A. 0.1 mmho
B. 100 mmho
C. 10 mmho
D. 0.01 mmho
E. none of the above

15. A cell membrane has a length constant of 2.0 mm. If you put an electrical probe into the cell membrane and the reading 2.0 mm from the point of insertion is +20 mV and a normal resting membrane potential is -80 mV, what have you raised the potential to at the point of insertion?

A. 270 mV
B. 100 mV
C. 190 mV
D. 120 mV
E. 130 mV

16. In a test subject, oxygen consumption was measured at 700 ml/min. Pulmonary artery oxygen content was 140 ml/L of blood and artery oxygen content was 210 ml/L of blood. Cardiac output was which of the following?

A. 4.2 L/min
B. 7.0 L/min
C. 10.0 L/min
D. 12.6 L/min
E. none of the above

17. Stroke volume is increased by

A. a sudden increase in venous constriction
B. an increase in venous compliance
C. an increase in heart rate
D. an increase in afterload
E. none of the above

Questions 18-19

Use the pressure volume curve illustrated below to determine the ejection fraction and diastolic pressure.

18. The ejection fraction equals

A. 0.50
B. 0.55
C. 0.60
D. 0.65
E. 0.70

19. The diastolic pressure equals

A. 0 mmHg
B. 5 mmHg
C. 70 mmHg
D. 90 mmHg
E. 120 mmHg

20. Stroke volume will be increased by increasing the contractile activity of all the following EXCEPT

A. venous vessels
B. arterial vessels
C. ventricles
D. atria
E. lymphatic vessels

Questions 21-24

Match the events in the cardiac cycle with the time points in the pressure tracings below.

21. Onset of isovolumetric ventricular contraction.

22. Closure of aortic valve.

23. Opening of mitral valve.

24. Atrial systole.

25. Based on the following values:
Average capillary hydrostatic pressure = 18 mmHg
Average capillary osmotic pressure = 27 mmHg
Average interstitial osmotic pressure = 7 mmHg

The flow of fluid out of the capillaries will be zero if the average interstitial hydrostatic pressure is

A. - 4 mmHg
B. - 2 mmHg
C. 0 mmHg
D. + 1 mmHg
E. + 2 mmHg

26. The graph below illustrates the pressure-volume curves for the arterial and venous systems. The ratio of the arterial compliance to the venous compliance is approximately

A. 15:1
B. 10:1
C. 1:1
D. 1:10
E. 1:20

27. The data below was obtained from a patient before and after administration of a drug that increased his mean right atrial pressure.

Before drug administration:
Mean right atrial pressure: 8 mmHg
Mean aortic pressure: 80 mmHg
Cardiac output: 4 L/min

After drug administration:
Mean right atrial pressure: 20 mmHg
Mean aortic pressure: 80 mmHg
Cardiac output: 5 L/min

The ratio of the patient's total peripheral resistance before drug administration to his total peripheral resistance after drug administration is:

A. 1:1
B. 3:2
C. 4:3
D. 5:4
E. 6:5

28. Which of the following changes in perfusion of an organ system is an example of pressure autoregulation?

A. The decrease in renal blood flow during hemorrhage.
B. The decrease in blood flow to the skin during exposure to a cold environment.
C. The increase in coronary perfusion during exercise.
D. The decrease in blood flow to alveoli during hypoxia
E. None of the above

29. Systemic arteriolar constriction may result from an increase in the total concentration of

A. nitric oxide
B. angiotensin II
C. atrial natriuretic peptide (factor)
D. beta agonists
E. hydrogen ion

30. All of the following would increase in response to a reduced stretch of the carotid baroreceptors EXCEPT

A. pulmonary capillary pressure
B. heart rate
C. venous tone
D. ventricular contractility
E. parasympathetic nerve activity

A) Only I is true
B) Only II is true
C) Both I and II are true
D) Both I and II are false

31. I. Septic shock involves vasodilator substances released from bacteria and anaphylactic shock involves the release of histamine in response to a severe allergic reaction.

II. Neurogenic shock usually involves a significant drop in total peripheral resistance.

32. I. When taking blood pressure, the first point at which you hear sound through the stethoscope on the arm indicates systolic pressure.

II. In pace maker cells of the heart, voltage sensitive sodium and calcium channels, play a role in depolarization of those cells.

33. I. In cardiac muscle, the t-tubules are found at the z discs.

II. All postganglionic sympathetic neurons use norepinephrine as their neurotransmitter.

34. I. Warm thermal receptors are sensitive to temperatures from 1-10 degrees centigrade above normal skin temperature. Normal skin temperature is about 34 degrees centigrade.

II. The plasma osmotic pressure is relatively constant throughout the capillary.

35. I. The closing of the AV values has a lower pitched sound than the closing of the semilunar valves.

II. Propranolol is a beta blocker.

36. I. According to Fick's 1st law of diffusion, if you double the concentration gradient then you will always double the diffusion rate assuming all other factors are equal.

II. Glucose transporters that directly use the sodium gradient to transport glucose is an example of a symporter carrier protein.

37. I. The difference between the intra-alveolar pressure and the intrapleural pressure is the transpulmonary pressure.

II. The compliance of a lung is mostly determined by the alveolar surface tension.

38. I. The CO2 binding site on the heme part of the hemoglobin is different from the O2 binding site.

II. In restrictive lung disease, lung compliance is abnormally low.

39. I. Loop diuretics inhibit Na-K-Cl co-transport in luminal membrane of the thick ascending loop of Henle.

II. NOS can effect the production of nitrous oxide by oxidizing arginine.

40. I. The A band of skeletal muscle is defined by the link of myosin in a myofibril.

II. The S1 portion of heavy meromyosin binds to actin in skeletal muscle.

Key:

1. C
2. B
3. D
4. C
5. D
6. B
7. C
8. B
9. B
10. B
11. D
12. E
13. B
14. E
15. C
16. C
17. A
18. C
19. C
20. B
21. B
22. E
23. F
24. A
25. B
26. E
27.B
28. E
29. B
30. E
31. C
32. A
33. A
34. C
35. C
36. C
37. C
38. B
39. A
40. C