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Blood Vessels and Circulation

Chapter 21
STUDY
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The smallest arterial branches are called the
precapillary arterioles
Venous valves are responsible for
channeling blood toward the heart.
Arrange the structures in the following list in the order that blood will encounter as it flows from the output side to the input side of the cardiovascular flow circuit.

1. venules
2. arterioles
3. capillaries
4. elastic arteries
5. medium veins
6. large veins
7. muscular arteries
4, 7, 2, 3, 1, 5, 6
Blood pressure is lowest in the
veins
In large arteries, the thick layer of elastic fibers is called the
internal elastic membrane
These vessels hold the largest percentage of the blood supply.
vein
Which of the following lumen diameters would be typical of a muscular artery?
0.4 cm or 4.0 mm
Complications related to arteriosclerosis account for roughly ________ percent of deaths in the United States.
50
Capillaries with a perforated lining are called
fenestrated capillaries
Compared to arteries, veins
have thinner walls
The muscular layer of a blood vessel is the
tunica media
The layer of the arteriole wall that can produce vasoconstriction is the
tuinca media
Materials can move across capillary walls by
filtration, reabsorption, and diffusion
These vessels may be continuous or fenestrated.
capillaries
Venae cavae are the largest of this type of vessel.
vein
Metabolites exchange by diffusion with tissue cells in which of the following locations?
capillary
RBCs move single file through this structure.
capillary
The brachial and femoral arteries are examples of which type of artery?
muscular
Which vessel is known as a resistance vessel?
arteriole
Blood flow through a capillary is controlled by the
precapillary sphincter
Capillaries that have a complete lining are called
continuous capillaries
Blood pressure is highest here.
artery
The thoroughfare channel ends at the
venule
Which of the following is the innermost layer of a blood vessel?
tunica intima
Pulmonary arteries carry blood to the
lungs
The common iliac artery is an example of which type of artery?
elastic
The inferior vena cava is classified as a(n)
large vein
Factors that increase the risk of atherosclerosis include which of the following?

lack of exercise
obesity
high cholesterol
smoking
all of the above
all of the above
Relative to the lumen, which of these vessels has the thickest tunica media?
arterioles
The large vessels that return blood to the heart are called
veins
The layer between the tunica media and the tunica externa in a large artery is the
external elastic membrane
Which of the following layers of a vessel contains collagen fibers with scattered bands of elastic fibers?
tunica externa
After blood leaves the capillaries, it enters the
venules
Elastic fibers in the walls of these vessels are stretched during systole.
arteries
A sample of tissue displays many large flattened spaces lined by fenestrated endothelium. Blood moves slowly through these spaces. This tissue sample most likely came from the
liver
You would expect to find fenestrated capillaries in
the pituitary
Venoconstriction ________ the amount of blood within the venous system, which ________ the volume in the arterial and capillary systems.
reduces; increases
Which of the following are the smallest venous vessels?
venules
A vein that measures 5 mm would be considered
medium vein
Which of the following is most likely to result from an aneurysm in a brain artery?
stroke
Venoconstriction reduces the diameter of which vessel?
vein
Blood moves forward through veins because of all of the following, except

pumping by the smooth muscle in the wall of the vein.
the respiratory pump.
valves in the veins preventing the backward flow of blood.
the pressure in the veins is lower than in the arteries.
muscular compression.
pumping by the smooth muscle in the wall of the vein.
Which of the following would have the greater effect on vascular resistance?

decreasing the diameter of a blood vessel by ½
doubling the length of a blood vessel
neither would be greater
decreasing the diameter of a blood vessel by ½
Which of the following statements is false concerning the movement of fluid between capillaries and interstitial space?

The hydrostatic pressure of the interstitial fluid is largely unimportant in determining fluid movement.
Blood hydrostatic pressure forces fluid from the capillary to the interstitial space.
Blood osmotic pressure moves fluid from the interstitial space to the capillary.
The net filtration pressure is usually zero.
The osmotic pressure of the interstitial fluid is less than the blood osmotic pressure.
The net filtration pressure is usually zero.
Edema is favored when
the plasma concentration of protein is reduced, endothelial permeability goes up, and capillary hydrostatic pressure is elevated.
The difference between the systolic and diastolic pressures is called the ________ pressure.
pulse
Which of the following factors will increase the net filtration pressure to move fluid out of capillaries?
both decreased plasma albumen and increased blood hydrostatic pressure
Total peripheral resistance is related to all of the following, except the

osmolarity of interstitial fluids.
blood viscosity.
flow characteristics.
blood vessel diameter.
length of a blood vessel.
osmolarity of interstitial fluids
The main control of peripheral resistance occurs in the
arteriole
If blood pressure doubled, the blood flow through a vessel would be
doubled
To defend blood volume against dehydration, the body
experiences a recall of interstitial fluids.
accelerates reabsorption of water at the kidneys.
experiences an increase in the blood colloidal osmotic pressure.
increases water intake.
Blood pressure is determined by
estimating the pressure needed to close off an artery with an external pressure cuff.
The blood colloid osmotic pressure mostly depends on the
concentration of plasma proteins
Blood pressure increases with all of the following, except increased

peripheral resistance.
blood volume.
parasympathetic innervation.
cardiac output.
force of cardiac contraction.
parasympathetic innervation
The continual movement of fluid through the interstitial spaces produced by capillary filtration serves which of the following functions?

accelerates the distribution of nutrients and hormones
helps carry toxins and bacteria to cells of the immune system
flushes hormones and wastes from the interstitial spaces
assists the transport of insoluble substances that cannot enter the capillaries
all of the above
all of the above
Turbulent blood flow occurs
when there are irregularities in the vessel wall, at high flow rates, and when there are sudden changes in vessel diameter.
When a person rises quickly from a sitting position,
the carotid baroreceptors become less active.
reflex vasoconstriction of peripheral blood vessels occurs.
venous return is decreased.
heart rate is reflexly elevated.
The vascular pressure that declines from roughly 35 mm Hg to about 18 mm Hg is the
capillary hydrostatic pressure
Averaged over a few heartbeats, venous return is ________ cardiac output.
equal to
Each of the following will cause an increase in blood pressure, except

increased levels of ANP (atrial natriuretic peptide).
increased levels of angiotensin II.
increased levels of aldosterone.
increased levels of ADH (antidiuretic hormone).
increased blood volume.
increased levels of ANP
Each of the following changes will result in increased blood flow to a tissue, except

increased vessel diameter.
increased hematocrit.
relaxation of precapillary sphincters.
increased blood pressure.
decreased peripheral resistance.
increased hematocrit
When carotid and aortic baroreceptors slow their discharge,
both heart rate and stroke volume increases
Each of the following will lead to a decrease in blood pressure, except

decrease in blood volume.
increased levels of aldosterone.
increased levels of ANP (atrial natriuretic peptide).
release of renin.
decreased peripheral resistance.
release of renin
Homeostatic mechanisms in response to blood loss include all of the following, except


increased thirst and water intake.
activation of aldosterone secretion.
uptake of interstitial fluid due to reduced capillary pressure.
activation of ADH secretion.
inhibition of EPO secretion.
inhibition of EPO secretion
Elevated levels of the hormones ANP and BNP will produce increased
salt and water loss through the kidneys
Blood flow to a tissue will increase if the
arterioles dilate
Stimulation of the aortic baroreceptors reflexly results in
increased activity by the parasympathetic nervous system.
When renin is released from the kidney
angiotensinogen is converted into angiotensin I.
Which of the following are characteristics of cardiovascular regulation?

blood flow through tissues meets the demand for oxygen
changes occur without drastically altering blood pressure
blood flow through tissues meets the demand for nutrients
blood flow changes to match tissue responses
all of the above
all of the above
Each of the following factors would increase cardiac output, except

increased blood concentration of glucose.
increased venous return.
increased sympathetic stimulation of the heart.
stimulation of the heart by epinephrine.
decreased parasympathetic stimulation of the heart.
increased blood concentration of glucose
Vickie has a tumor that secretes excess amounts of the hormone aldosterone. Because of the elevated level of hormone, she exhibits
both increased blood pressure and increased body stores of sodium ion.
Fear can result in
increased stimulation of the cardioaccelerator center by higher brain centers.
Which of the following is greater?

normal stroke volume
stroke volume during circulatory shock
Both are about the same.
normal stroke volume
In response to hemorrhage, there is
peripheral vasoconstriction and mobilization of the venous reserve only
Which of the following changes doesn't occur during exercise compared to rest?

Abdominal viscera blood flow is lower.
Heart blood flow is higher.
Cardiac output is higher.
Skin blood flow is lower.
Kidney blood flow is lower.
skin blood flow is lower
Increased levels of carbon dioxide in the blood will result in decreased
parasympathetic stimulation of the heart
In comparing a trained athlete to a nonathlete, which of these comparisons is false?

The athlete has a higher exercise stroke volume.
Both hearts weigh about the same.
The athlete has a lower resting heart rate.
The athlete has a higher exercise cardiac output.
The athlete has a higher resting stroke volume.
both hearts weigh about the same
If a person has a blood pressure of 120/90, his mean arterial pressure would be ________ mm Hg.
100
ADH and aldosterone secretion are part of the body's long-term compensation for
a serious hemorrhage
Paul has a horrible chainsaw accident and cuts several major blood vessels in his head and neck. As a result of this injury, you would expect to observe all of the following, except a(n)

increased total peripheral resistance.
cold, clammy skin.
increased secretion of renin by the kidneys.
increase in cardiac output.
increased heart rate.
increase in cardiac output
The hormone that produces cardiovascular effects similar to activation of the sympathetic nervous system is:
epinephrine
During exercise

venous return increases.
both cardiac output and stroke volume increase.
vasodilation occurs at the active skeletal muscles.
all of the above
vasodilation occurs at the active skeletal muscles and both cardiac output and stroke volume increase.
all of the above
Each of the following factors would increase peripheral resistance, except

elevated levels of epinephrine.
irregularities in the vessel walls caused by plaques.
elevated hematocrit.
vasodilation.
increased sympathetic stimulation.
vasodilation
When will the blood pressure be greater?

when the peripheral vessels dilate
when the peripheral vessels constrict
Neither is greater.
when the peripheral vessels constrict
After losing 25 percent of blood volume in a motorcycle accident, which of the following compensatory responses would occur?

venoconstriction of skin vessels
increase of contractility
vasoconstriction of the body wall
increased heart rate
all of the above
all of the above
Which of the following conditions is least likely to lead to renin release?

hypertension
circulatory shock
renal artery thrombus
vasospasm of the renal arteries
increased sympathetic activity
hypertension
Pulmonary veins carry blood to the
left atrium
The internal carotids and the basilar artery are interconnected by an anastomosis called the
cerebral arterial circle
The two vertebral arteries fuse to form a large artery, the
basilar artery
The external iliac artery branches to form the ______ arteries
femoral and deep femoral
Near the level of vertebra L4, the aorta branches to form the ________ arteries.
common iliac
Nutrients from the digestive tract enter the
hepatic portal vein
The ________ divides the aorta into the thoracic aorta and the abdominal aorta.
diaphragm
The brachial artery branches to form the radial and ________ arteries.
ulnar
After passing the first rib, the subclavian artery becomes the ________ artery.
axillary
After entering the arm, the axillary artery becomes the ________ artery.
brachial
Which of the following is a deep vein of the forearm?

basilic
cephalic
hemiazygos
radial
azygos
radial
The two common iliac veins form the
inferior vena cava
At the knee, the femoral artery becomes the ________ artery.
popliteal
The fusion of the brachiocephalic veins forms the
superior vena cava
The ________ vein is formed by the fusion of the greater saphenous vein, femoral vein, and deep femoral vein.
external iliac
Blood from the brain returns to the heart through the ________ vein.
internal jugular
The vessel that receives blood from the head, neck, chest, shoulders, and arms is the
superior vena cava
The superior sagittal sinus collects blood from the
bran
The radial and ulnar veins fuse to form the ________ vein.
brachial
An important artery that supplies blood to the brain is the ________ artery.
internal carotid
Branches off the aortic arch include the

left common carotid artery.
left subclavian artery.
brachiocephalic trunk.
all of the above
left subclavian artery and left common carotid artery only
all of the above
Near the carotid sinus,
the common carotid divides into an internal and an external branch.
Veins of the upper arm include the ________ vein(s).
basilic, cephalic, brachial
The vein that is formed from the fusion of the subclavian with the internal and external jugulars is the ________ vein.
brachiocephalic
Which of the following obeys the rule that arteries carry blood away from the heart?

common carotid artery
marginal artery
left descending artery
right coronary artery
left circumflex artery
common carotid artery
Each of the following arteries is a component of the cerebral arterial circle, except the

anterior communicating artery.
posterior cerebral artery.
anterior cerebral artery.
basilar artery.
posterior communicating artery.
basilar artery
Major branches of the subclavian artery include the ________ artery(ies).
lateral thoracic
Branches of the thoracic aorta include all of the following, except the ________ arteries.

basilar
esophageal
bronchial
superior phrenic
intercostal
basilar
Which of these is not a property of AIDS?

almost always eventually fatal.
is spread most often through sexual contact
attacks the T helper (CD4) cells
has killed at least ½ million people in the United States
is declining worldwide
declining worldwide