MAP chapter 21

Blood flow through a capillary is controlled by the A. thoroughfare channel. B. precapillary sphincter. C. venule. D. vasa vasorum. E. plexus.

B

Capillaries that have a complete lining are called A. sinusoidal capillaries. B. continuous capillaries. C. fenestrated capillaries. D. vasa vasorum. E. sinusoids.

B

Hemorrhage triggers all of these responses EXCEPT __________. A. an increase in heart rate B. an increase in urine production C. release of the venous reserve D. an increase in erythropoiesis

B

A decrease in blood pressure at the arterial baroreceptors would result in which of the following? A. a decrease in cardiac output B. vasodilation of arterioles C. an increase in heart contractility D. a decrease in heart rate

C

Averaged over a few heartbeats, venous return is ________ cardiac output. A. much higher than B. somewhat higher than C. equal to D. somewhat lower than E. much lower than

C

Blood pressure increases with all of the following except increased A. cardiac output. B. peripheral resistance. C. parasympathetic innervation. D. blood volume. E. force of cardiac contraction.

C

Each of the following factors would increase peripheral resistance except A. irregularities in the vessel walls caused by plaques. B. elevated hematocrit. C. vasodilation. D. elevated levels of epinephrine. E. increased sympathetic stimulation.

C

Exchange between a blood vessel and the cells that surround it can occur only in A. arteries. B. venules. C. capillaries. D. arterioles. E. veins.

C

If blood pressure is increased at the arterial baroreceptors, what would happen with the activity level of the parasympathetic nervous system (PNS) and sympathetic nervous system (SNS)? A. decreased PNS activity and increased SNS activity B. increased PNS and SNS activity C. increased PNS activity and decreased SNS activity

C

In the case of hemorrhage, the body mobilizes all these defenses EXCEPT __________. A. increased thirst B. increased heart rate C. decreased ADH secretion D. increased peripheral resistance

C

The muscular layer in the wall of a blood vessel is the tunica A. interna. B. adventitia. C. media. D. externa. E. intima.

C

The only vessels whose walls are thin enough to exchange materials with the surrounding cells are __________. A. arteries B. veins C. capillaries D. arterioles

C

Arteries have a structure in their middle and internal vessel walls that veins lack, called a/an __________. A. smooth muscle B. adventitia C. endothelium D. elastic membrane

D

Atherosclerosis has been associated with high blood pressure. What is it called when a person has a blood pressure of 158/99? A. normal B. hypotension C. pre-hypertension D. stage 1 hypertension

D

Atherosclerosis is characterized by the buildup of arterial plaque. When plaque first begins to form, on which part of the blood vessel do the monocytes bind after taking in cholesterol-rich lipoproteins? A. the internal elastic membrane B. the tunica media C. the tunica externa D. the endothelial lining

D

Blood pressure is lowest in the A. arteries. B. arterioles. C. capillaries. D. veins. E. venules.

D

Elevated levels of the natriuretic peptide hormones ANP and BNP will produce increased A. blood volume. B. sodium ion levels in blood. C. venous return and preload. D. salt and water loss through the kidneys. E. blood pressure.

D

Increased levels of carbon dioxide in the blood will result in decreased A. blood flow to the lungs. B. cardiac output. C. sympathetic stimulation of the heart. D. parasympathetic stimulation of the heart. E. heart rate.

D

Stimulation of the adrenal medulla would result in which of the following? A. vasodilation of arteries B. a decrease in cardiac output C. a decrease in blood pressure D. an increase in heart rate and contractility

D

The blood colloid osmotic pressure mostly depends on the A. concentration of plasma sodium ions. B. concentration of plasma glucose. C. number of red blood cells. D. concentration of plasma proteins. E. concentration of plasma waste products.

D

The vascular pressure that declines from roughly 35 mm Hg to about 18 mm Hg is the A. diastolic pressure. B. peripheral pressure. C. pulse pressure. D. capillary hydrostatic pressure. E. venous pressure.

D

Total peripheral resistance is related to all of the following except the A. length of a blood vessel. B. turbulence. C. blood vessel diameter. D. osmolarity of interstitial fluids. E. blood viscosity.

D

When muscle cells contract, they release substances that cause nearby precapillary sphincters to relax. This is an example of __________. A. neural regulation B. endocrine regulation C. positive feedback regulation D. autoregulation

D

Which of the following changes take place when you begin to exercise? A. increase in venous return B. a rise in sympathetic activity C. extensive vasodilation D. All of the above changes take place as you begin to exercise.

D

Compared to arteries, veins A. have a pleated endothelium. B. hold their shape better when cut. C. are more elastic. D. have more smooth muscle in their tunica media. E. have thinner walls.

E

Each of the following factors would increase cardiac output except A. increased venous return. B. increased sympathetic stimulation of the heart. C. stimulation of the heart by epinephrine. D. decreased parasympathetic stimulation of the heart. E. increased blood concentration of glucose.

E

Each of the following will lead to a decrease in blood pressure except A. decrease in blood volume. B. decreased peripheral resistance. C. increased levels of ANP (atrial natriuretic peptide). D. decreased levels of aldosterone. E. release of renin.

E

Factors that increase the risk of atherosclerosis include which of the following? A. lack of exercise B. smoking C. obesity D. high cholesterol E. All of the answers are correct.

E

Pulmonary arteries carry blood to the A. right atrium. B. left atrium. C. aorta. D. systemic circuit. E. lungs.

E

These vessels may be continuous or fenestrated. A. venules B. arteries C. arterioles D. veins E. capillaries

E

Venous valves are responsible for A. preventing anterograde flow. B. regulating blood pressure in veins. C. preventing blood from re-entering a ventricle. D. channeling blood away from the heart. E. channeling blood toward the heart.

E

Blood pressure is determined by A. estimating the pressure needed to close off an artery with an external pressure cuff. B. estimating the degree of turbulence in a partly closed vessel. C. measuring the size of the pulse. D. measuring the force of contraction of the left ventricle. E. listening carefully to the pulse.

A

Each of the following will cause an increase in blood pressure except A. increased levels of ANP (atrial natriuretic peptide). B. increased levels of angiotensin II. C. increased levels of aldosterone. D. increased blood volume. E. increased levels of ADH (antidiuretic hormone).

A

Stenosis is a permanent narrowing of an artery, as with arteriosclerosis. Which of the following could occur with stenosis of a renal artery? Feedback loop blood pressure regulation A. Renin secretion will increase. B. Anemia will occur. C. Epinephrine secretion will increase. D. Urine output will increase.

A

The main control of peripheral resistance occurs in the A. arteriole. B. vein. C. capillary. D. artery. E. venule.

A

The peak blood pressure measured during ventricular systole is called __________. A. systolic pressure B. pulse pressure C. diastolic pressure D. mean arterial pressure

A

Vascular resistance is the friction force that opposes blood flow in a blood vessel. What two factors are the most important in generating friction between blood and the walls of a vessel? A. blood vessel diameter and length B. blood flow velocity and turbulence C. blood viscosity and turbulence D. blood pressure and volume

A

What vessels hold the largest percentage of the blood supply? A. veins B. arteries C. venules D. capillaries E. arterioles

A

If the capillary hydrostatic pressure is elevated, what consequences will this have on the surrounding tissues? A. Increased capillary hydrostatic pressure will cause a corresponding increase in pressure in the venular end of the capillary bed, causing plasma backflow into the tissues. B. Increased capillary hydrostatic pressure will cause excess interstitial fluid accumulation in the surrounding tissues. C. Increased capillary hydrostatic pressure will cause increased blood pressure, which could cause damage to the capillaries, allowing blood seepage into the surrounding tissues. D. Increased capillary hydrostatic pressure will facilitate greater exchange with the surrounding tissues, reducing buildup of the interstitial fluid in the tissues by pulling it into the capillaries.

B

When renin is released from the kidney, A. angiotensin I increases salt reabsorption at the kidneys. B. angiotensinogen is converted into angiotensin I. C. blood flow to the kidneys decreases. D. blood pressure goes down. E. angiotensin I is converted to angiotensin II.

B

Which of the following would cause vasodilation of arterioles? A. increased activity of the sympathetic nervous system B. decreased activity of the sympathetic nervous system C. decreased activity of the parasympathetic nervous system D. increased activity of the parasympathetic nervous system

B

What is the relationship between high blood pressure and edema? A. High blood pressure leads to decreased CHP and thus filtration exceeds reabsorption. B. High blood pressure causes a decrease in BCOP and thus reabsorption declines. C. High blood pressure leads to increased CHP and thus filtration exceeds reabsorption. D. all of the above

C

Where are the sensors for the arterial baroreceptor reflex located? A. cardiovascular centers in the medulla oblongata B. The sympathetic and parasympathetic nervous systems C. carotid sinus and aortic arch

C

Which of the following is normally the greatest source acting against blood flow? A. turbulence B. viscosity of blood C. vascular resistance D. venous pressure E. vessel length

C

Which part of the blood vessel wall is dominated by smooth muscle? A. the tunica externa B. the endothelium C. the tunica media D. the tunica intima

C