Chapter 21

1. What carries blood under high pressure from the heart to tissue?

Arteries

2. ________ is the forces involved in circulating blood.

Hemodynamics

3. Arteries hold what type of volume?

Stressed volume

4. ________ are the last small branches off arterial tree.

Arterioles

5. Where is the site of highest resistance to blood flow?

Arterioles

6. Metarterioles emerge from _____ and supply a small group (10-100) of ______

which contribute to a capillary bed.

Arterioles; capillaries

7. What is the name of the vessel that is thin enough to allow exchange of nutrients;

blood; fluid; etc?

Capillary

8. What structure collects blood from capillary and merges with veins?

Venules

9. Veins bring blood _____ the heart.

Back to

10. Veins are a major what of blood?

Reservoir

11. What are the names of vessels of vessels that line the walls of large vessels?

Vasa vasorum

12. Name the 3 structures of arteries and veins.

Tunica intima- endothelium basement membrane

Tunica media- smooth muscle (external) elastic fibers

Tunica externa ( adventitia)- merges with connective tissue surrounding blood

vessel

13. What is the largest layer in the artery?

Tunica media

14. What type of artery is the aorta?

Elastic (conducting artery)- has smaller amount of smooth muscle and greater amount

of elastic tissue

15. What vessels play a key role in regulating blood flow by regulating resistance?

Arterioles

16. The vascular smooth muscle is innervated by what part of the autonomic system?

Sympathetic

17. True/False. A small change in the diameter of your arteries due to plaque build up

or loss of elasticity has a small or little effect on the flow.

False – it has a huge impact; causes 90% blockage

18. What term means intermittent contraction and relaxation of sphincter that allow

filling of capillary beds?

Vasomotion

19. What is the function of capillaries?

Exchange of nutrients and waste between blood and tissue fluid

20. What is the structure of a capillary?

Single layer of simple squamous epithelium and its basement membrane

21. Name the 3 types of capillaries and describe.

Continuous – no fenestrae; pores

Fenestrated – have pores

Sinusoidal- large diameter with large fenestrae; pores

22. Which types of capillaries have the fastest diffusion? Slowest diffusion?

Sinusoids; continuous

23. True/False. Veins have valves.

True

24. Veins hold what type of “volume”?

Unstressed

25. Tell the differences between arteries and veins.

Arteries- thicker walls; circular; under pressure; no valves; more elastic; carries

blood from hear.

Veins. - thinner walls; less muscle; irregular shape; not under pressure; has valves; c

carries blood to the heart.

26. If the aorta becomes stiff due to ware and tear what effect will the stiffness have on

blood flow?

The blood will flow more in spurts and not in a constant cyclic manner.

27. What causes varicose veins?

Leaky venous valves

28. What controls blood flow to each tissue?

The tissue need

29. What controls the cardiac output?

Mainly by the sum of all local tissue flow

30. True/False. Arterial pressure is controlled independently of either local blood flow

or cardiac output.

True

31. What percentage of blood volume at rest is in the systemic veins and venules?

60%

32. What ways do capillaries move materials in and out?

Diffusion; transcytosis; filtration; reabsorption

33. If filtration exceeds reabsorption where is material moving?

Out of capillary

34. If reabsorption exceeds filtration where is material moving?

Into the capillary

35. What do you want the rate of filtration to rate of reabsorption to be in the

capillaries?

Equal to each other

36. What is promoted by hydrostatic pressure and interstitial flow osmotic pressure?

Filtration

37. What is promoted by blodd collid osmotic pressure and interstitial fluid hydrostatic

pressure?

Reabsorption

38. What is Starling’s law of capillaries?

The volume of fluid and solutes reabsorbed is almost as large as the volume filtered

39. Do you have net reabsorption or filtration on the arterial sid of the capillaries?

Filtration

40. Do you have net reabsorption or filtration on the venous side of the capillaries?

Reabsorption

41. Where does the excess fluid go that is not reabsorbed on the venous side of the

capillaries?

Lymphatic capillaries collect it

42. High blood pressure promotes what?

Filtration

43. Low blood pressure promotes what?

Reabsorption

44. Blood collid osmotic pressure (BCOP) should be higher of lower on the venous side

of the capillaries?

Higher

45. If I drink pure water I will promote filtration or reabsorption?

Filtration

46. If I eat salty foods I would promote filtration or reabsorption?

Reabsorption

47. If BHP= 30mmHg IFOP=2mmHg IFHP = 3mmHg and BCOP = 26mmHg on

arterial side of capillaries what is the net filtration?

NFP= (30 +2) – (26 + 3) = 3mmHg

48. Pressure exerted by blood on walls of a vessel is caused by _______.

Contraction of the ventricles

49. Pressure exerted by blood on wall of a vessel is highest where?

In aorta

50. Greatest drop in pressure occurs where?

In arterioles

51. Pulse pressure is difference between what?

Systolic and diastolic

52. If a patient has a normal BP (120/80) what is their pulse pressure?

40 (120 -80=40)

53. What is mean arterial blood pressure (MABP)?

Average pressure in arteries (not an arithmetic average)

54. What is the equation for MABP?

MABP=diastolic BP +1/3(systolic BP – diastolic BP)

55. Why is it 1/3(systolic BP – diastolic BP) in the MABP equation?

Because it is not an arithmetic average

56. Blood pressure is measured by listening for what?

Korotkoff sounds – produced by turbulent flow in arteries as pressure released from

BP cuff.

57. What are the two “pumps” are in the venous return?

Skeletal muscle and respiratory

58. Where do you take blood pressure at?

At level of heart at brachial artery

59. What is the first sound you hear when you take blood pressure? (systolic or

diastolic)

Systolic

60. What is the second sound you herar when you take blood pressure? (systolic or

diastolic)

Diastolic

61. What factors affect circulation?

Pressure differences that drive the blood flow; resistance to flow; and venous return

62. What is the velocity of blood flow equation?

V=Q/A

63. Where is the greatest cross-sectional area?

In capillaries

64. As diameter of vessels decreases the total cross-sectional area ______ and velocity

of blood flow ____.

Increases; decreases

65. Speed of blood flow in cm/sec is _____ related to cross-sectional area.

Inversely

66. Blood flow is slower in arterial or venous branches?

Arterial

67. Blood flow becomes faster when vessels merge to form ______.

Veins

68. Circulation time is what?

Time it takes a drop of blood to travel from the right atrium back to the right atrium.

69. As vessel diameter increases the velocity of fluid flow through the vessel _____.

Decreases

70. Magnitude of Q in Q=∆P/R equation is _____ proportional to ∆P.

Directly

71. Magnitude of Q in Q=∆P/R equation is _____ proportional to R (resistance).

Inversely

72. What are the 2 resistance arrangements?

In series and in parallel

73. If you add resistance in parallel a(n) _____ happens to resistance. In series?

Decrease; increase in resistance

74. What are the advantages of having vessels in parallel?

Total resistance is less than any of the individual resistance; no loss of pressure; if

another resistance total decreases; if increase resistance total increases.

75. What does Poiseulle’s law state?

The flow of (Newtonian) fluid through rigid tubes is governed by pressure gradient

and resistance to flow.

76. What are the 3 properties that affect fluid and tube resistance in Poiseuille’s law?

Length of tube (l); radius of tube (r); viscosity of fluid (ŋ)

77. What is the Poiseuille’s law equation?

R=8 ŋl/(π r4)

78. Does a smaller vessel offer more/ less resistance to blood flow.

More

79. An increase in viscosity _____ resistance.

Increases

80. The longer the vessel the ______ the resistance to flow.

Greater

81. Resistance is regulated by what?

The radius of the vessel

82. Very small changes in the radius will have ______ affects on the resistance.

Huge

83. Name some cases where blood viscosity can change?

Dehydration; change in hematocrit; and changes in plasma protein concentration.

84. The greater the _____ the slower the flow.

Length

85. The greater the _____ the greater the flow.

Radius

86. Obesity would lead to hypo/hypertension.

Hypertension

87. What are laminar and turbulent flow?

Laminar- streamlined; outermost layer moving slowest and center moving faster.

Turbulent- interrupted; rate of flow exceeds critical velocity; fluid passes a constricton

sharp turn rough surfaces.

88. In normal conditions turbulent flow is found only where?

In aorta

89. What is critical velocity?

Laminar flow velocity increases with increase in pressure but up to a point

90. What type of flow is observed above critical velocity?

Turbulent

91. Reynolds number is used to predict what?

Whether blood flow will be laminar or turbulent

92. The viscosity of blood decreases with _____ in flow rate.

Increase

93. RBC tend to collect in center of lumen thus _____ the effective viscosity.

Reducing

94. Axial streaming reduces blood viscosity at ____ thus ____ resistance.

Edge; decreasing

95. What effect does decreased resistance have on flow?

It increases it

96. A high hematocrit as in plycytemia increases blood viscosity which _____ blood

flow through capillaries.

Slow

97. What is shear thinning?

The apparent viscosity diminishes as the blood flow rate increases (and vice versa)

98. The higher the compliance of a vessel the _____ volume it can hold at a given

pressure.

More

99. Aging decreases/ increases compliance of vessels.

Decreases

100. What do changes in compliance cause?

Redistribution of blood between arteries and veins

101. What is the equation for compliance?

C=V/P

102. What type of pump has steady pressure steady flow and no need for compliance?

Constant flow pump

103. What has the highest compliance? Middle? Lowest?

Veins; arteries; aging arteries

104. Cyclical pump and non-compliance vessels have what type of pressure and flow?

Intermittent

105. Cyclical pump and compliant vessels have what type of pressure and flow?

Steady

106. Laplace’s law states what?

It relates pressure; radius of vessel and tension on vessel wall

107. The importance of Laplace’s law is in what vessels?

Capillaries and alveoli

108. What is the term that means input during physical activity?

Proprioceptors

109. This term means changes in pressure within blood vessel?

Baroreceptors

110. What receptors monitor concentration of chemicals in the blood?

Chemoreceptors

111. What type of fibers does the vagus nerve have and what effect does it have on the

heart? Parasympathetic; decreases heart rate

112. Name the 2 type of baroreflexes of blood pressure.

Carotid sinus reflex and aorta reflex

113. What cranial nerve is involved in the carotid sinus reflex? the aorta reflex?

Glossopharyngeal (CN IX) vagus (CN X)

114. What is orthostatic hypotension?

Decrease in BP upon standing. Blood is pulled down to the lower extremities.

115. Locally systemic vessels _______ in response to low levels of oxygen. Pulmonary

vessels ________ in response to low oxygen.

Dilate; constrict

116. The aortic valve is _________ in this chart. Compliance is _________ in the

chart.

Narrowing; decreasing.

117. What effect does epinephrine and norepinephrine have on heart rate and force of

contraction?

Increases heart rate and increases the force of contraction

118. Which is the only hormone that decreases BP?

ANP (atrial natriuretic peptide)

119. Renin-angotensin-aldosterone mechanism occurs do to what?

A decrease in blood pressure

120. Renin activates what in the liver? Into what?

Angiotensinogen; angiotensin I

121. Aldosterone promotes what?

Reabsorption of Na

122. What effect does aldosterone have on the kidneys if there is low blood pressure?

Increases water reabsorption and decreases urine volume.

123. What effect does increasing water reabsorption and decreasing urine volume in the

kidneys have on blood pressure?

Increases blood pressure

124. What type of shock is due to loss of blood or body fluids?

Hypovolemic

125. What type of shock is caused by damage to pumping action of the heart?

Cardiogenic

126. What type of shock causes a drop in BP?

Vascular

127. What do osmoreceptors detect?

Increased osmotic pressure in blood vessels

128. What term means the failure of the cardiovascular system to deliver enough

oxygen and nutrients?

Shock

129. What type of shock could be due to hemorrhage sweating or diarrhea?

Hypovolemic

130. Cardiogenic shock could be caused by what?

MI, ischemia, valve problems or arrhythmias

131. What type of injury or trauma would cause vascular shock?

Head trauma

132. ______ shock is caused by blockage of circulation (pulmonary embolism)

obstructive

133. circulation is left side heart to body & back to heart

Systemic

134. _______ circulation is capillaries of GI tract to capillaries in liver

Hepatic portal

135. circulation is right-side heart to lungs & back to heart?

Pulmonary

136. The hepatic portal system is a subdivision off of what circulation system?

Systemic circulation

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