Blood Vessels

Front 1

When does blood flow through two consecutive capillary networks before returning to the heart?

Back 1

In a portal system

Front 2

____ is a point where two blood vessels merge

Back 2

anastomosis

Front 3

When does blood flow from an artery directly into a vein, bypassing the capillaries.

Back 3

In an arteriovenous anastomosis (shunt)

Front 4

Where do shunts naturally occur and why?

Back 4

fingers, palms, toes and ears; to control heat loss

Front 5

In an ____ two arteries merge and provide collateral routes of blood supply to a tissue.

Back 5

arterial anastomosis

Front 6

In a ____ two veins merge, providing several alternative routes of drainage from an organ.

Back 6

venous anastomosis

Front 7

The three layers of blood vessel walls from superficial to deep.

Back 7

Tunica externa
Tunica media
Tunica intima(interna)

Front 8

Which blood vessel layer merges with the connective tissue of neighboring blood vessels, nerves or other organs

Back 8

Tunica externa

Front 9

Which blood vessel layer anchors the vessel and provides passage for small nerves, lymphatic vessels, and smaller blood vessels

Back 9

Tunica externa

Front 10

Clotting of blood vessels

Back 10

atherosclerosis

Front 11

Hardening of blood vessels

Back 11

arterosclerosis

Front 12

Composition of the tunica externa

Back 12

Loose connective tissue

Front 13

What are the small vessels that supply blood to the outer half of the wall of larger blood vessels.

Back 13

vasa vasorum

Front 14

The thickest blood vessel layer

Back 14

Tunica media

Front 15

The blood vessel layer that consists of smooth muscle, collagen, and sometimes elastic tissue

Back 15

Tunica media

Front 16

The blood vessel responsible for vasoconstriction and vasodilation

Back 16

Tunica media

Front 17

Baroreceptors are located...
A) in the aorta and subclavian arteries.
B) in the aorta and carotid arteries.
C) aorta and carotid veins.
D) aorta and subclavian veins.
E) aorta and common iliac arteries.

Back 17

b

Front 18

Action potentials are conducted from the baroreceptors to the brain via...
A) the vagus nerve.
B) the vagus and glossopharyngeal nerves.
C) the vagus and phrenic nerves.
D) the phrenic and glossopharyngeal nerves.
E) the phrenic nerve.

Back 18

b

Front 19

The action potential from the brain to the heart travels along...
A) the vagus nerve.
B) the vagus and glossopharyngeal nerves.
C) the vagus and phrenic nerves.
D) the phrenic and glossopharyngeal nerves.
E) the phrenic nerve.

Back 19

a

Front 20

Heart rate and stroke volume decrease under decreased parasympathetic stimulation.
A) True
B) False

Back 20

B

Front 21

Increased sympathetic stimulation causes vasodilation, bringing elevated blood pressure back to normal.
A) True
B) False

Back 21

b

Front 22

Chemoreceptors in the carotid and aortic bodies detect all of the following except...
A) oxygen levels
B) blood pressure
C) pH
D) carbon dioxide
E) both A and D

Back 22

b

Front 23

Chemoreceptors are also located in the...
A) medulla oblongata.
B) pons.
C) hypothalamus.
D) thalamus.
E) spinal cord.

Back 23

a

Front 24

Which of the following will not increase the heart rate?
A) decreased blood oxygen
B) increased blood carbon dioxide
C) increased blood pressure
D) decreased blood pH

Back 24

c

Front 25

Increased sympathetic stimulation causes increased heart rate and stroke volume.
A) True
B) False

Back 25

a

Front 26

Chemoreceptors in the hypothalamus monitor blood carbon dioxide and pH.
A) True
B) False

Back 26

b

Front 27

The fluids leave the capillaries at the arterial end because...
A) the net filtration pressure of the blood is higher at the arterial end than it is at the venous end.
B) the net filtration pressure of the blood is higher at the venous end than it is at the arterial end.
C) the net filtration pressure of the interstitial fluid is higher at the arterial end than it is at the venous end.
D) the net filtration pressure of the interstitial fluid is higher at the venous end than it is at the arterial end.
E) the osmotic pressure is higher at the arterial end than it is at the venous end.

Back 27

a

Front 28

The fluids reenter the capillaries at the venous end because...
A) the net filtration pressure of the blood is higher at the arterial end than it is at the venous end.
B) the net filtration pressure of the blood is higher at the venous end than it is at the arterial end.
C) the net filtration pressure of the interstitial fluid is higher at the arterial end than it is at the venous end.
D) the net filtration pressure of the interstitial fluid is higher at the venous end than it is at the arterial end.
E) the osmotic pressure is higher at the venous end than it is at the arterial end.

Back 28

d

Front 29

Approximately what percent of fluid that exits the capillaries at the arterial end renters the capillaries at the venous end?
A) 60%
B) 70%
C) 80%
D) 90%
E) 100%

Back 29

d

Front 30

The lymphatic capillaries reabsorb as much as 20% of the fluid lost by the blood capillaries.
A) True
B) False

Back 30

b

Front 31

The net osmotic pressure is equal at both the arterial and the venous ends of the capillary.
A) True
B) False

Back 31

a

Front 32

Veins contain thick layers of smooth muscle and play a major role in regulating systemic blood pressure.
A) True
B) False

Back 32

b

Front 33

Circulatory shock can occur when output from the sympathetic nervous system is suddenly inhibited.
A) True
B) False

Back 33

a

Front 34

Diastolic pressure is the peak arterial BP reached during ventricular contraction, and systolic pressure is the minimum arterial BP between heartbeats.
A) True
B) False

Back 34

b

Front 35

What is the MABP in an individual with a blood pressure of 150/90?
A) 110
B) 120
C) 130
D) 150

Back 35

a

Front 36

The baroreceptors
A) transmit signals continually to the brainstem.
B) increase their signaling rate when the blood pressure rises.
C) excite the vagal nerves to the heart and dilate the arteries to lower BP.
D) all of the above

Back 36

d

Front 37

Reduced capillary reabsorption of fluid can lead to edema. Which of the following does not contribute to edema?
A) liver disease
B) dietary protein deficiency
C) extreme muscular activity
D) kidney diseases

Back 37

c

Front 38

Which of the following types of low venous return (LVR) shock occurs when released histamine causes extensive generalized vasodilation?
A) anaphylactic shock
B) septic shock
C) hypovolemic shock
D) neurogenic shock

Back 38

a

Front 39

Which of the following is not one of the three major branches arising from the aortic arch?
A) brachiocephalic trunk
B) left common carotid artery
C) left subclavian artery
D) right common carotid artery

Back 39

d

Front 40

In contrast to the superficial veins, the deep veins run parallel to the arteries and have similar names.
A) True
B) False

Back 40

a

Front 41

Blood vessels that connect two capillary networks are called:
A) portal systems
B) anastomoses
C) arterial systems
D) veins
E) capillary plexuses

Back 41

a

Front 42

The tissue layer of a vessel that differs most in thickness when comparing arteries and veins is the:
A) tunica externa
B) tunica adventitia
C) tunica media
D) tunica interna
E) tunica intima

Back 42

c

Front 43

These have the most control of perfusion of a capillary bed:
A) muscular arteries
B) precapillary sphincters
C) elastic arteries
D) sinusoids
E) fenestrated capillaries

Back 43

b

Front 44

These structures, present in medium-sized veins, prevent backflow of blood:
A) precapillary sphincters
B) venous tunica
C) skeletal muscles
D) fenestrations
E) venous valves

Back 44

e

Front 45

All of these factors may increase peripheral resistance except:
A) blood viscosity
B) length of vessel
C) radius of vessel
D) blood type
E) polycythemia

Back 45

d

Front 46

Venous pooling in a soldier standing at attention for a prolonged time occurs mainly when this mechanism fails:
A) cardiac suction
B) respiratory pump
C) skeletal muscle pump
D) gravity
E) pressure gradient

Back 46

c

Front 47

Venous anastomoses are more common than arterial anastomoses.
A) True
B) False

Back 47

a

Front 48

The smooth muscle in the walls of blood vessels is found in which of the following layers?
A) tunica adventitia
B) tunica media
C) tunica intima
D) all of the above

Back 48

b

Front 49

There is not enough blood in the body to fill the entire vascular system at once. About how much of the body's capillaries is closed at any given time?
A) 1/4
B) 1/3
C) 1/2
D) 3/4

Back 49

d

Front 50

Veins have lower blood pressure than arteries, averaging about 80mm Hg, in contrast to the 120mm Hg seen in large arteries during systole.
A) True
B) False

Back 50

a

Front 51

Arteries:
A) typically have a thicker tunica media than veins
B) contain a lower blood pressure than veins
C) may contain one-way valves
D) depend upon the massaging action of the skeletal muscles for a continuous flow of blood

Back 51

a

Front 52

Hypertension is a chronic resting blood pressure higher than which of the following?
A) 140/70
B) 120/80
C) 130/70
D) 140/90

Back 52

d

Front 53

Because of their ability to expand during systole and recoil during diastole, the elastic arteries "smooth out" changes in blood pressure.
A) True
B) False

Back 53

a

Front 54

A three-fold increase in the radius of a blood vessel produces an 81-fold increase in blood flow.
A) True
B) False

Back 54

a

Front 55

Accumulation of lactic acid in an active skeletal muscle promotes vasodilation to that muscle.
A) True
B) False

Back 55

a

Front 56

The most important mechanism of exchange between blood and tissue fluid is:
A) transcytosis
B) diffusion
C) filtration
D) active transport

Back 56

b

Front 57

The venous return of blood back to the heart is encouraged by
A) constriction of veins in the legs
B) a drop in internal pressure in the abdomen during inhalation
C) relaxation of skeletal muscle
D) gravity acting on the large veins above the heart

Back 57

d

Front 58

Both systemic and pulmonary arteries dilate in response to local hypoxia.
A) True
B) False

Back 58

b

Front 59

Vasodilation may be brought about by:
A) histamine
B) high blood oxygen
C) high blood carbon dioxide
D) angiotensin II

Back 59

a

Front 60

At the arterial end of a capillary:
A) net filtration pressure exceeds net reabsorption pressure
B) net filtration pressure is less than net reabsorption pressure
C) blood pressure is less than osmotic pressure
D) blood pressure is equal to osmotic pressure

Back 60

a

Front 61

Which of the following types of blood vessels has a thick tunica media, one-way valves, and carry blood back toward the heart?
A) arterioles
B) venules
C) elastic arteries
D) medium size veins

Back 61

d

Front 62

Blood flows from venules to:
A) capillaries
B) arterioles
C) medium sized veins
D) the heart

Back 62

c

Front 63

Which of these vessels has the largest lumen?
A) large artery
B) medium sized artery
C) venous sinus
D) large vein

Back 63

d

Front 64

Most medium-sized arteries are named for the organ or tissue they feed.
A) True
B) False

Back 64

a

Front 65

The outermost layer of all blood vessels is the:
A) tunica externa
B) tunica media
C) tunica intima

Back 65

a

Front 66

When net filtration pressure is greater than net reabsorption pressure more fluid enters the capillary than leaves it.
A) True
B) False

Back 66

b

Front 67

When a precapillary sphincter is closed, blood bypasses that capillary bed and travels directly from a _______ through a _______ to a venule.
A) arteriole, capillary
B) arteriole, thoroughfare channel
C) distributing artery, capillary bed

Back 67

b

Front 68

The vessels that supply the largest blood vessels with nutrients and remove waste are called:
A) tunica endothelium
B) metarteriole
C) vasa vasorum
D) portal system

Back 68

c

Front 69

The connective tissue of this vessel layer anchors the vessel and provides passage for lymphatic vessels:
A) tunica adventitia
B) tunica intima
C) tunica media
D) endothelium

Back 69

a

Front 70

As the diameter of a blood vessel increases, the resistance of blood flow:
A) decreases
B) increases
C) remains the same

Back 70

a

Front 71

Which type of capillary is the most "leaky"?
A) continuous capillaries
B) fenestrated capillaries
C) thoroughfare capillaries
D) sinusoids

Back 71

b

Front 72

Blood flows faster through the superior vena cava when you inhale.
A) True
B) False

Back 72

b

Front 73

Which statement does not accurately describe veins? (a) They have less elastic tissue and smooth muscle than arteries, (b) they contain more fibrous tissue than arteries, (c) most veins in the extremities have valves, (d) they always carry deoxygenated blood.

Back 73

d

Front 74

Smooth muscle in the blood vessel wall (a) is found primarily in the tunica intima, (b) is mostly circularly arranged, (c) is most abundant in veins, (d) is usually innervated by the parasympathetic nervous system.

Back 74

b

Front 75

Peripheral resistance (a) is inversely proportional to the length of the vascular bed, (b) increases in anemia, (c) is decreased in obesity, (d) is inversely related to the diameter of the arterioles.

Back 75

d

Front 76

Which of the following can lead to decreased venous return of blood to the heart? (a) an increase in blood volume, (b) an increase in venous pressure, (c) damage to the venous valves, (d) increased muscular activity.

Back 76

c

Front 77

Arterial blood pressure increases in response to (a) increasing stroke volume, (b) increasing heart rate, (c) arteriosclerosis, (d) rising blood volume, (e) all of these.

Back 77

e

Front 78

Which of the following would not result in the dilation of the feeder arterioles and opening of the precapillary sphincters in systemic capillary beds? (a) a decrease in local tissue O2 content, (b) an increase in local tissue CO2, (c) a local increase in histamine, (d) a local increase in pH.

Back 78

d

Front 79

The structure of a capillary wall differs from that of a vein or an artery because (a) it has two tunics instead of three, (b) there is less smooth muscle, (c) it has a single tunic—only the tunica intima, (d) none of these.

Back 79

c

Front 80

The baroreceptors in the carotid sinus and aortic arch are sensitive to (a) a decrease in CO2, (b) changes in arterial pressure, (c) a decrease in O2, (d) all of these.

Back 80

b

Front 81

The myocardium receives its blood supply directly from (a) the aorta, (b) the coronary arteries, (c) the coronary sinus, (d) the pulmonary arteries.

Back 81

b

Front 82

Blood flow in the capillaries is steady despite the rhythmic pumping of the heart because of the (a) elasticity of the large arteries, (b) small diameter of capillaries, (c) thin walls of the veins, (d) venous valves.

Back 82

a

Front 83

In atherosclerosis, which layer of the vessel wall thickens most? (a) tunica media, (b) tunica intima, (c) tunica adventitia, (d) tunica externa.

Back 83

b

Front 84

Suppose that at a given point along a capillary, the following forces exist: capillary hydrostatic pressure (HPc) = 30 mm Hg, interstitial fluid hydrostatic pressure (HPif) = 0 mm Hg, capillary colloid osmotic pressure (OPc) = 25 mm Hg and interstitial fluid colloid osmotic pressure (OPif) = 2 mm Hg. The net filtration pressure at this point in the capillary is (a) 3 mm Hg, (b) –3 mm Hg, (c) –7 mm Hg, (d) 7 mm Hg.

Back 84

d