practice test Flashcards
1
Q
- In most tissue beds, blood flow is regulated in proportion to which of the following?
a. arterial blood pressure
b. cardiac output
c. local metabolism
d. mean circulatory filling pressure
A
c. local metabolism
2
Q
2. Consider the resistance in the following tissue beds: coronary = .40 mmHg/ml/min brain = .13 mmHg/ml/min liver = .08 mmHg/ml/min kidneys = .10 mmHg/ml/min
What is the total peripheral resistance?
a. greater than .71 b. between .08 and .4 c. less than .08 d. undeterminable
A
c. less than .08
3
Q
2. Consider the resistance in the following tissue beds: coronary = .40 mmHg/ml/min brain = .13 mmHg/ml/min liver = .08 mmHg/ml/min kidneys = .10 mmHg/ml/min
- Using the data from question 2, which tissue bed would have the greatest flow?
a. coronary
b. brain
c. liver
d. kidneys
A
c. liver
4
Q
- In the following vessels the flow rate is identical, which vessel is offering the greatest resistance to flow?
a. P1 50 P2 25
b. P1 70 P2 60
c. P1 80 P2 65
A
a P1 50 P2 25
5
Q
- A broad band Doppler reading is indicative of what type of flow?
a. laminar
b. turbulent
c. intermittent
d. flow has ceased
A
b. turbulent
6
Q
- If a vessel with a length of 100 cm has a cross sectional area of .5 cm2 , and velocity of flow of 10 cm/sec. The pressure drop across that length is 10 mmHg. What is the flow in that vessel?
a. 10 ml/min
b. 20 ml/min
c. 100 ml/min
d. 200 ml/min
e. 300 ml/min
A
P = V (A) P = 10 cm/sec (.5cm2) P = 5 ml/sec (60 sec/min)
P = 300 ml/min
e. 300 ml/min
7
Q
- The vascular compartment with the greatest total cross sectional area is which of the following?
a. aorta
b. large arteries
c. capillaries
d. large veins
A
c. capillaries
8
Q
- Which of the following is not characteristic of parallel circuitry?
a. independence of flow control
b. maximizes total peripheral resistance
c. maximizes oxygen delivery to tissues
d. decreases work load on the heart
A
b. maximizes total peripheral resistance
9
Q
- A small change in volume producing a large change in pressure is characteristic of which vascular compartment?
a. systemic arteries
b. systemic veins
c. microcirculation
d. all of the above
A
a. systemic arteries
10
Q
- Acetylcholine binding to the vascular endothelium has what effect?
a. vasodilatation by causing nitric oxide release
b. vasodilatation by causing adenosine release
c. vasoconstriction by triggering muscle spasm
d. vasoconstriction by stimulating the sympathetic nervous system
A
a. vasodialation caused by nitric oxide release
11
Q
- What is the effect of sympathetic nervous stimulation on most vascular smooth muscle?
a. vasodilatation mediated by alpha receptors
b. vasodilatation mediated by beta receptors
c. vasoconstriction mediated by alpha receptors
d. vasoconstriction mediated by beta receptors
A
c. vasoconstriction mediated by alpha receptors
12
Q
- During widespread sympathetic nervous system stimulation, which tissue bed would show the least increase in vascular resistance?
a. stomach
b. kidney
c. lung
d. liver
A
c. lung
13
Q
- As a tissue becomes more active, how is blood flow to that tissue increased?
a. tissue releases local vasodilators
b. reflex increase in systemic blood pressure
c. sympathetic induced local vasodilatation
d. parasympathetic induced local vasodilatation
A
a. tissue releases local vasodilators
14
Q
- At a given mean circulatory filling pressure what happens to venous return as central venous pressure increases?
a. increases
b. decreases
c. stays constant
A
b. decreases
15
Q
- If cardiac output is stopped, arterial pressure will be expected to fall until it equals which of the following?
a. critical closing pressure
b. mean circulatory filling pressure
c. pulse pressure
d. central venous pressure
A
a. critical closing pressure
16
Q
- In a healthy young adult comment about tissue flow during diastole?
a. it ceases
b. maintained by recoil of the arteries
c. maintained by release of local vasodilators
d. maintained by parasympathetic vasodilatation
A
b. maintained by recoil of the arteries
17
Q
- If blood flow to a tissue doubles from 200 ml/min to 400 ml/min, and the AV O2 difference falls from .05 ml O2/ml to .025 ml O2/ml. Comment on the increase in flow.
a. it is a functional increase in flow
b. it is due to an increase in tissue metabolism
c. it is likely due to shunting
d. it is due to the release of local vasodilators
A
c. it is likely due to shunting
18
Q
- What increases the plasma colloid osmotic effect by about 50%?
a. positive charges on protein attracting and holding negative ions like chloride
b. negative changes on protein attracting and holding positive ions like sodium
c. the large quantity of fibrinogen that is converted to fibrin
d. the natural charge attraction of sodium and cloride
A
b. negative changes on protein attracting and holding positive ions like sodium
19
Q
- Which of the following effects is not attributed to slow breathing (6 breaths/minute)?
a. increased resting oxygen saturation
b. increased sympathetic activity
c. decreased chemoreflex activation
d. decreased mean arterial blood pressure
A
b. increased sympathetic activity
20
Q
- What effect does decreasing velocity have on blood viscosity?
a. increases
b. decreases
c. no effect
A
a. increases
21
Q
- How does fibrinogen decrease blood viscosity?
a. causes local vasodilation
b. by thinning out plasma
c. makes RBC’s more flexible
d. reduces the number of RBC’s
A
c. makes RBC’s more flexible
22
Q
Use the following graph to answer questions 22-23
VR
0 5 10 CVP
- Considering vascular function as central venous pressure increases, what happens to venous return?
a. increases
b. decreases
c. stays constant
A
b. decreases
23
Q
- What is the mean circulatory filling pressure equal to?
a. 0 mmHg b. 5 mmHg c. 10 mmHg d. 15 mmHg
A
c. 10 mmHg
24
Q
- The chronic use of anti-inflammatory drugs could be expected to inhibit which of the following processes?
a. local vasodilatation
b. angiogenesis
c. glomerular filtration
d. hydraulic filtering
A
b. angiogenesis
25
Q
- Consider the following data:
average capillary hydrostatic P = 17 mmHg
average capillary colloid osmotic P = 28 mmHg
average interstitial hydrostatic P = -2 mmHg
average interstitial colloid osmotic P = 9 mmHg
a. filtration > reabsorption b. filtration
A
c. filtration = reabsorption
26
Q
- Which brainstem area is tonically active and is associated with a tonic SNS outflow?
a. neurons associated with the nucleus tractus solitarius
b. neurons anterolateral in the upper medulla and pons
c. neurons anterolateral in the lower medulla
d. neurons posteromedially in the medulla
A
b. neurons anterolateral in the upper medulla and pons
27
Q
- Which of the following substance is associated with local vasodilatation?
a. norepinephrine
b. angiotensin II
c. antidiurectic hormone
d. adenosine
A
d. adenosine
28
Q
- What high resistance microvessels control local blood flow by intergrating multiple input which determine lumen diameter?
a. arterioles
b. capillaries
c. venules
d. large arteries
A
a. arterioles
29
Q
- Compare the distensibility of the following vessels.
Vessel one: Vessel two:
Orig vol. = 20 ml Orig vol. = 10 ml
vol = 1 ml vol = 1 ml
pressure = 2 mmHg pressure = 2 mmHg
a. vessel one is more distensible than vessel two b. vessel two is more distensible than vessel one c. vessel one and vessel two are equally distensible
A
distensibility = ^Vol/^P (iVol) vessel 1 = 1ml/2mmHg (20ml) = 10
vessel 2 = 1ml/2mmHg (10ml) = 5
b. vessel two is more distensible than vessel one
30
Q
- Which of the following may act at the level of the CNS in the development of hypotension?
a. acetylcholine
b. norepinephrine
c. adenosine
d. nitric oxide
A
d. nitric oxide
31
Q
- In the kidney, how does SNS stimulation, increase angiotensin formation?
a. by stimulation of the JG cells to release angiotensin
b. by stimulation of the JG cells to release renin
c. by stimulation of the vasa recti to release vasopressin
d. by stimulation of the adrenal cortex to release aldosterone
A
b. by stimulation of the JG cells to release renin
32
Q
- In response to a fall in systemic arterial blood pressure, which of the following changes would be counterproductive in offsetting that fall?
a. increase in SNS stimulation
b. increase in renin release
c. increase in vasopressin release
d. increase in ANP release
A
d. increase in ANP release
33
Q
- In the face of rising arterial blood pressure, which of the following responses would autoregulate both renal blood flow and glomerular filtration?
a. constriction of the afferent arterioles
b. constriction of the efferent arterioles
c. dilation of the afferent arterioles
d. dilation of the efferent arterioles
A
a. constriction of the afferent arterioles
34
Q
- What effect does stimulation of baroreceptors, have on sympathetic outflow?
a. increases
b. decreases
c. no effect
A
b. decreases
35
Q
- During systole, what is happening to baroreceptor activity?
a. increasing
b. decreasing
c. stays constant
A
a. increasing
36
Q
- In the fetus, the ductus arteriosis shunts blood from the pulmonary artery to the aorta returning primarily from what vessel?
a. inferior vena cava
b. superior vena cava
c. azygous veins
d. umbilical veins
A
b. superior vena cava
37
Q
- What is the function of the ductus venosus in the fetus?
a. shunt blood from the pulmonary artery into the aorta
b. shunt blood from the right atrium into the left atrium
c. shunt blood from the umbilical vein into the inferior vena cava
d. shunt blood away from the lungs
A
c. shunt blood from the umbilical vein into the inferior vena cava
38
Q
- In which of the following tissue beds does sympathetic nervous system stimulation cause a metabolically induced local increase in blood flow?
a. heart
b. active skeletal muscle
c. GI tract
d. brain
A
a. heart
39
Q
- During exercise, which of the following normally decreases?
a. heart rate
b. active muscle blood flow
c. diastolic blood pressure
d. VO2
A
d. VO2
40
Q
- During exercise most of the increase in cardiac output is due to which of the following?
a. increase in heart rate
b. increase in stroke volume
c. decrease in central venous pressure
d. increase in ventilation
A
a. increase in heart rate
