Download DIRECTIONS: Each group of questions below consists of a number

DIRECTIONS: Each group of questions below consists of a number of lettered headings or a
diagram or table with a number of lettered components, followed by a list of numbered words,
phrases or statements. For each numbered word, phrase or statement, select the one lettered
component that is most closely associated with it Each lettered heading or lettered component
ay be selected once more than once or not at all m
(A) aorta
(B) arteriole in the brain
(C) capillary in the big toe
(D) femoral vein
(E) inferior vena cava
In a normal, healthy individual who is lying down at rest:
1.
the vessel in which the velocity of blood flow is the slowest
2.
the vessel in which the mean end pressure is the lowest
3.
the vessel in which the pulse pressure is the greatest
DIRECTIONS: Each of the questions or incomplete statements below is followed by live
suggested answers or completions. Select the that is MST in each case.
4. Venous return and heart rate remain unchanged while ventricular end systolic volume
decreased. At this new steady state, one can conclude that
(A) cardiac output increased.
(B) atrial pressured decreased.
(C) ventricular end-diastolic volume increased.
(D) mean arterial pressure decreased.
(E) stroke volume increased.
5. Aortic systolic pressure remains unchanged while aortic pulse pressure decreased. At this new steady
state.
(A) mean aortic pressure decreased.
(B) heart rate decreased.
(C) afterload increased.
(D) ventricular contractility decreased.
(E) total peripheral resistance decreased.
6. In a normal, healthy individual, ventricular end-diastolic pressure and ventricular end
systolic volume remain unchanged while heart rate decreased. At this new steady state.
(A) stroke volume decreased.
(B) central venous pressure decreased.
(C) venous return remained unchanged.
(D) ventricular preload remained unchanged.
(E) none of the above have occurred.
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7. If ventricular contractility and preload remain unchanged, an increase in total peripheral
resistance will
(A) not alter aortic diastolic pressure.
(B) decrease stroke volume.
(C) decrease ventricular end diastolic volume.
(D) increase ventricular end diastolic pressure.
(E) decrease ventricular end systolic pressure.
8. Which of the following best indicates that ventricular contractility has increased:
(A) increased stroke volume
(B)ventricular end diastolic volume decreased and contractile force remained unchanged
(C) heart rate is unchanged and cardiac output increased
(D) atrial pressure increased as contractile force increased
(E) increased stroke work
9. Aortic systolic pulse pressure coincides with
(A) the end of the reduced cardiac ejection phase.
(B) aortic value closure.
(C) ventricular end systolic pressure.
(D) the start of the first heart sound.
(E) blood flow from the left ventricle equaling flow across the TPR.
10. An increase in venoconstriction will result in a(n)
(A) increase in TPR.
(B) decrease in mean arterial pressure.
(C) decrease in venous return.
(D)increase in mean circulatory filling pressure.
(E) decrease in cardiac output.
11. For a few heart beats following an instantaneous increase in TPR,
(A) cardiac contractility decreases.
(B) cardiac output is greater than flow across the TPR.
(C) central venous pressure increases.
(D) mean circulatory filling pressure increases.
(E) vascular function curve shifts up and to the right.
12. Cutting the carotid sinus nerves will result in
(A) an increase in heart rate.
(B) a decrease in mean circulatory filling pressure.
(C) a decrease in total TPR.
(D) cerebral ischemia.
(E) a decrease in mean arterial pressure.
13. A restriction of flow in the renal artery results in a(n)
(A) increase in mean arterial pressure.
(B) increase in blood levels of vasopressin.
(C) decrease in release of renin.
(D)increase in unstressed volume.
(E) decrease in the firing rate of carotid baroreceptors.
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14. An increase in the steady-state, mean arterial perfusion pressure to an organ that results in
little or no increase in blood flow to that organ is an example of
(A) reactive hyperemia.
(B) active hvperemia.
(C) the Cushing response.
(D) extrinsic control of blood flow.
(E) pressure-flow autoregulation.
15. Coronary blood flow
(A) does not exhibit pronounced pressure-flow autoregulation.
(B) is regulated primarily by Active hyperemia.
(C) is regulated extensively by sympathetic input to coronary arterioles.
(D) is greatest during ventricular systole.
( E) increases little with exercise.
16. An increase in core body temperature results in a(n)
(A) increase in TPR.
(B) decrease in cardiac output.
(C) decrease in sympathetic neural input to cutaneous arterioles.
(D, decrease in cerebral blood flow.
(E) significant increase in mean arterial pressure.
17. The new cardiovascular state in figure could be produced by venous infusion of
(A) renin.
(B) vasopressin.
(C) an agonist at muscarinic receptors.
(D) norepinephrine.
(E) plasma.
18. If cardiovascular parameters were measured in an astronaut first while standing at rest on
earth and then while resting aboard the international Space Station, which of the
following changes would most likely be observed:
(A) an increase in mean arterial pressure (measured at the level of the heart)
(B) a decrease in aortic blood flow
(C) an increase in pressure in the capillaries of her toes
(D) an increase in jugular venous pressure
(E) an increase in pulmonary blood flow
19. The following laboratory values were obtained on an experimental animal:
Arterial
Arterial PCO2
pH 7.4
80 mmHg
The plasma [HCO3 ] in mmoles/l would be:
(A) 6
(B) 12
(C) 24
(D) 36
(E) 48
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20. A patient in acute diabetic ketoacidosis is observed to be hyperventilating. The main
drive for the increased ventilatory rate most likely is
(A) a fall in the plasma [HCO3].
(B) an increase in the plasma PCO2 due to reaction of the kctoacids with HCO3
(C) H+ stimulation of central chemoreceptors.
(D) an increase in the arterial [H+].
(E) CO2 stimulation of central chemoroceptors.
21. An experimental animal is on a ventilator with pure oxygen. When the ventilatory rate is
increased there is a fall in the arterial PCO2. Why is there a fall in arterial PCO2?
(A) Since the animal is on a ventilator there is less energy expenditure and thus less
production of CO2.
(B) Alveolar PCO2 is solely dependent upon the ventilatory rate.
(C) There is low CO2 in the inspired gas.
(D) Excretion of CO2 is greater than the rate of CO2 production due to the higher rate
of ventilation.
(E) None of the above.
22. If you mix 100 ml of blood with a PO2 = 0 mmHg with 100 ml of blood with a PO2 = 200
mm Hg, the PO2 of the 200 ml of mixed blood would be
(A) 12 mmHg.
(B) 28 mmHg.
(C) 40 mmHg.
(D) 75 mmHg.
(E) 100 mmHg.
23. A patient breathing air has a PaO2 = 70 mmHg and a PaCO2 = 40 mmHg. When you
administer an agent that causes an increase in cardiac output thereby decreasing the
amount of time blood spends within the pulmonary capillaries. PaO2 does not decrease.
When you allow the patient to breath 100% O2, PaO2 increases to 655 mmHg. The most
likely cause of the initial low PaO2 when the patient was breathing air is
(A) pulmonary shunt.
(B) limited diffusion.
(C) ventilation/perfusion inequality.
(D) hypoventilation.
(E) ventilation of unperfused alveoli.
24. A patient has an FEV1/FVC = 45% (normal = 80%) and a functional residual capacity = 4
L (normal = 2.3 L). Which one of the following is most likely responsible for the
findings?
(A) airway obstruction by mucus
(B) decreased lung elastic recoil
(C) weak muscles of respiration
(D) airway smooth muscle contraction
(E) pneumothorax
25. A patient has reduced total lung capacity and increased residual volume. Functional
residual capacity (FRC) is normal. There is no history of excess mucus production.
These findings are most consistent with which of the following diseases or conditions?
(A) emphysema
(B) chronic bronchitis
(C) pulmonary fibrosis
(D) neuromuscular disease
(E) pneumothorax
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26. A subject was given an experimental drug. Several hours later, studies showed marked
instability of alveoli and an intrapleural pressure = -30 cm H2O. The findings arc most
likely due to the drug
(A) inducing airway smooth muscle contraction.
(B) decreasing lung elastic recoil.
(C) increasing mucus production.
(D) inactivating surfactant.
(E) reducing contraction of respiratory muscles.
27. In a patient with difficulty breathing, you find total lung volume and functional residual
capacity are within normal limits, but FEV1/FVC = 40% (normal = 80%). These findings
are most likely due to
(A) decreased lung compliance.
(B) loss of lung elastic recoil.
(C) airway smooth muscle contraction.
(B) neuromuscular disease.
(E) complete obstruction of airflow to one lobe of the lung.
28. As a result of an acute myocardial infarction, pulmonary venous pressure increases to 12
mmHg (normal = 5 mmHg). If cardiac output is normal, which of the following changes
from normal in pulmonary arterial pressure would most likely occur: a(n)
(A) increase by 7 mmHg.
(B) decrease by 7 mmHg.
(C) increase by 1 mmHg.
(D) increase by 12 mmHg.
(E) decrease by 5 mmHg.
29. If a patient with blockage of airflow to the right lung is given a drug that causes
pulmonary vascular smooth muscle relaxation, but no change in cardiac output,blood
flow to the left lung would
(A) increase.
(B) decrease.
(C) not change.
30. A normal subject with an alveolar ventilation rate = 4,000 ml/min and a PaCO2 = 40
mmHg voluntarily increases his alveolar ventilation to 8,000 ml/min. If the metabolic
CO2 production does not change, the PaCO2 after the increase in ventilation would most
likely be
(A) 80 mmHg.
(B) 60 mmHg.
(C) 40 mmHg.
(D) 20 mmHg.
(E) 10 mmHg.
31. The following data are obtained on a patient breathing air at sea level: Pa02 - 68 mmHg,
PaCO2 = 60 mmHg, pHa = 7.3? and R = 0.8. CO2 production is normal. The abnormal
blood gas data are due most likely to
(A) shunt.
(B) ventilation/perfusion inequality.
(C) hypoventilation.
(D) diffusion limitations at the alveoli.
(E) airflow to unperfused alveoli.
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32. In a patient breathing without assistance, PaO2 = 80 mmHg, PaCO2 = 50 mmHg, pHa
7.32. When you allow the patient to breathe gas containing supplemental O2, PaO2
increases to 160 mmHg. The PaCO2 with the patient breathing the gas with supplemental
02 would most likely be
(A) 25 mmHg.
(B) 40 mmHg.
(C) 50 mmHg.
(D) 60 mmHg.
(E) 80 mmHg.
33. A patient with anemia has 50% of the normal blood concentration of hemoglobin and a
PaO2 = 100 mmHg. Compared to the blood from a normal subject with a PaO2 = 100
mmHg, the patient's
(A) arterial blood would contain 50% as much bound O2.
(B) arterial hemoglobin saturation would be 50%.
(C)O2 binding capacity of hemoglobin would be 50%.
(D) arterial blood would have 50% as much O2 in the dissolved form.
(E) arterial blood would contain the same O2 concentration.
34. During a procedure to sample CSF (normal pH = 7.32). a small amount of buffer with a
pH of 7.2 is accidentally infused near the chemosensitive area of a patients brain stem.
An arterial blood sample taken shortly after the infusion would most likely show which
of the following sets of data?
A.
B.
C.
D.
E.
PaO2 (mmHg)
110
75
110
110
75
PaCO2 (mmHg)
20
50
20
50
50
pHa
7.6
7.4
7.2
7.2
7.6
35. The following data were collected from a subject one hour after she parachutes to a
mountain camp: PaO2 = 45 mmHg, PaCO2 = 30 mmHg, pHa = 7.5, alveolar ventilation
rate = 6,000 ml/min. Which of the following sets of data would most likely be collected
from the same subject after she has spent 3 days in the camp?
A.
B.
C.
D.
E.
PaO2 (mmHg)
45
55
57
55
70
PaCO2 (mmHg)
30
23
44
40
40
pHa
7.5
7.45
7.6
7.35
7.4
Alv. Ventilation ( ml/min_)
6,000
8,000
8,000
8,000
4,200
36. A 45-year old patient reports difficulty breathing, excessive mucus production every day
for 2 years and swollen ankles. You find pulmonary arterial pressure is elevated, but left
atrial pressure is normal. The patient's hemoglobin concentration is 20% above normal.
These findings are most consistent with
(A) pulmonary fibrosis.
(B) emphysema.
(C) asthma.
(D) polio.
(E) chronic bronchitis.
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37. In normal subjects at low lung volumes, expiratory flow rate is independent of effort.
Which of the following mechanisms is responsible for the effort-independent flow?
(A) airway smooth muscle contraction
(B) mucus obstruction of airways
(C) dynamic compression of airways
(D) respiratory muscles not being at their optimal lengths for contraction
(E) reduced lung compliance at the lower lung volumes
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ANSWERS:
1.
2.
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37.
C
E
A
B
C
D
B
B
E
D
B
A
A
E
B
C
D
D
E
D
B
B
C
B
D
D
C
C
B
D
C
C
A
A
B
E
C
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