General

Question 1

Capillaries are best described as ____________. A) thin walled vessels which permit exchange of materials between blood and interstitial fluid. B) thick walled vessels which convey blood away from the heart. C) thin walled vessels which convey blood toward the heart. D) thick walled vessels which carry blood rich in oxygen. E) thin walled vessels which carry blood deficient in oxygen.

Answer 1

A) thin walled vessels which permit exchange of materials between blood and interstitial fluid.

Question 2

Valves are found _________. A) in the heart B) in the veins C) in the arteries D) A and B E) A, B, and C

Answer 2

D) A and B

Question 3

The driving force of blood flow is a(n) __________ gradient. A) osmotic B) volume C) pressure D) gravity

Answer 3

C) pressure

Question 4

Vascular resistance is related to the ____________. A) length of a blood vessel B) diameter of a blood vessel C) nature of the blood flow (turbulent vs lamellar) D) viscosity of the blood E) A, B, C, and D

Answer 4

E) A, B, C, and D

Question 5

Each of the following changes will result in increased blood flow to a tissue EXCEPT ______. A) increased blood volume B) decreased vessel diameter C) increased blood pressure D) decreased peripheral resistance

Answer 5

B) decreased vessel diameter

Question 6

As blood vessel length increases, ____________. A) resistance increases B) flow decreases C) friction decreases D) A and B E) A, B and C

Answer 6

D) A and B

Question 7

The steep repolarization of phase 3 of the cardiac contractile cell’s action potential is due to which ion(s)? A) Ca2+ B) K+ C) Na+ D) A and B E) A and C

Answer 7

B) K+

Question 8

Phase 2 (plateau) of the cardiac contractile cell action potential is due to a combination of _________. A) Na+ efflux and K+ influx B) Na+ influx and Ca++ influx C) Ca++ efflux and K+ influx D) Ca++ influx and K+ efflux

Answer 8

D) Ca++ influx and K+ efflux

Question 9

The volume of blood ejected from each ventricle during a contraction is called the ________. A) end-diastolic volume B) end-systolic volume C) stroke volume D) cardiac output E) cardiac reserve

Answer 9

C) stroke volume

Question 10

Each of the following factors will increase cardiac output EXCEPT _______. A) Increased venous return B) Increased parasympathetic stimulation C) Increased sympathetic stimulation D) Increased heart rate

Answer 10

B) Increased parasympathetic stimulation

Question 11

Ventricular contraction begins just after ________ begins. A) P wave B) QRS complex C) T Wave D) PR segment E) ST segment

Answer 11

B) QRS complex

Question 12

Ventricular repolarization occurs during ____. A) P wave B) QRS complex C) T Wave D) PR segment E) ST segment

Answer 12

C) T Wave

Question 13

Atrial depolarization occurs during _____ A) P wave B) QRS complex C) T Wave D) PR segment E) ST segment

Answer 13

A) P wave

Question 14

Each of the following conditions would increase the heart rate EXCEPT _______. A) increased sympathetic stimulation of nodal fibers B) increased parasympathetic stimulation of nodal fibers C) increased levels of epinephrine in the interstitial fluid surrounding the myocardium D) increased permeability of the myocardial membrane to sodium ion

Answer 14

B) increased parasympathetic stimulation of nodal fibers

Question 15

If the blood pressure doubled at the same time that the peripheral resistance were doubled, the blood flow through a vessel would be _____. A) doubled B) halved C) 16 times greater D) 1/16 as much E) unchanged

Answer 15

E) unchanged

Question 16

Abnormally slow conduction through the ventricles would change the ________in an EKG. A) P wave B) T wave C) QRS complex

Answer 16

C) QRS complex

Question 17

The main site of variable resistance in the systemic circulation, contributing more than 60% of the total resistance are ____. A) muscular arteries B) elastic arteries C) arterioles D) venules E) veins

Answer 17

C) arterioles

Question 18

When a person rises quickly from a prone position, ____. A) the carotid baroreceptors become more active B) venous return is unchanged C) reflex vasoconstriction of the peripheral blood vessels occurs D) heart rate decreases

Answer 18

C) reflex vasoconstriction of the peripheral blood vessels occurs

Question 19

Parasympathetic stimulation of the sinoatrial (SA) node will _________. A) hyperpolarize the pacemaker cells B) decrease the heart rate C) increase the rate of depolarization D) A and B E) A and C

Answer 19

D) A and B

Question 20

Stretching a myocardial cell ___________. A) decreases the force of a contraction B) allows more Ca2+ to enter C) increases the force of contraction D) A and B E) B and C

Answer 20

E) B and C

Question 21

Ventricular repolarization in the human heart: a. begins in the same location and travels in the same direction as the depolarization wave. b. results from phase 2 of the fast action potential in myocytes. c. is represented by the T wave on the electrocardiogram. d. A and C

Answer 21

c. is represented by the T wave on the electrocardiogram.

Question 22

AV valves of the heart open and close because of: a. nervous impulses to papillary muscles b. passive recoil of valves c. changes in pressure in adjacent chambers d. mechanical stretching of the fibers attached to the valves as the myocardium contracts and relaxes

Answer 22

c. changes in pressure in adjacent chambers

Question 23

The region of the heart that normally has the highest rate of spontaneous action potentials is the: a. Purkinje fibers b. Atrioventricular (AV) node c. Bundle of HIS d. Sinoatrial (SA) node

Answer 23

d. Sinoatrial (SA) node

Question 24

Which of the following is most closely equal to increased left ventricular afterload? a. increased end-diastolic volume b. increased end-diastolic pressure c. increased end-systolic pressure d. increased stroke volume

Answer 24

c. increased end-systolic pressure

Question 25

Due to differences in opposing forces, there is usually a net _____ occurring at the arteriolar end of most capillaries coupled with net ___ at the venous end. a. absorption; filtration b. filtration; absorption

Answer 25

b. filtration; absorption

Question 26

When the baroreceptors respond to a decrease in blood pressure, the: a. heart rate slows b. peripheral resistance increases c. peripheral resistance decreases d. A and C

Answer 26

b. peripheral resistance increases

Question 27

Dilation of the arterioles in a single organ would lead to: a. an increase in pressure in the large arteries of that organ b. an increase in capillary pressure in that organ. c. a decrease in both capillary and venous pressures in that organ d. a decrease in blood flow to that organ resulting from the decreased blood pressure

Answer 27

b. an increase in capillary pressure in that organ.

Question 28

In an individual whose large elastic arteries (e.g., aorta) have relatively normal diameters, but a severely reduced compliance. You would expect: a. an elevated diastolic pressure b. a greatly reduced venous pressure c. a reduced systolic pressure d. an elevated pulse pressure

Answer 28

d. an elevated pulse pressure

Question 29

Increasing venous return increases cardiac output by: a. decreasing end diastolic volume b. increasing the stroke volume c. decreasing the ejection fraction d. A, B and C

Answer 29

b. increasing the stroke volume

Question 30

If blood pressure doubled at the same time that peripheral resistance doubled, the blood flow through a vessel would be: a. doubled b. halved c. 16 times greater d. unchanged

Answer 30

d. unchanged

Question 31

Contrast the following: (i) velocity of blood flow in capillaries (ii) velocity of blood flow in aorta a. (ii) > (i) b. (i) = or nearly = (ii) c. (i) > (ii)

Answer 31

a. (ii) > (i)

Question 32

Joan rose quickly from her bed to answer the front doorbell. In response to rising, her baroreceptors: a. decreased firing b. had no change in their firing rate c. increased firing

Answer 32

a. decreased firing

Question 33

In hyperemia, there is increased blood flow to the tissues. Reactive hyperemia is caused by: a. allergens such as bee venom or pollen b. decreased parasympathetic stimulation of the arterioles c. a local accumulation of metabolites due to reduced blood flow d. A, B and C

Answer 33

c. a local accumulation of metabolites due to reduced blood flow

Question 34

The swollen belly of a child that has insufficient dietary protein (malnutrition) is due to edema (fluid retention in the interstitium, ISV). This occurs because: a. the oncotic pressure of the blood is increased due to a lack of proteins (albumin) b. the resulting loss of red blood cells (anemia) decreases mean arterial pressure (MAP) c. lymph drainage is blocked d. the oncotic pressure in the blood is reduced due to a lack of proteins (albumin)

Answer 34

d. the oncotic pressure in the blood is reduced due to a lack of proteins (albumin)

Question 35

To compensate for blood loss due to a large hemorrhage (25% of blood volume), blood flow would: a. decrease to the brain but near normal to the kidneys b. be near normal to the brain and to the kidneys c. decrease to both the brain and the kidneys d. be near normal to the brain but decreased to the kidneys

Answer 35

d. be near normal to the brain but decreased to the kidneys

Question 36

In hypertension, the systolic blood pressure is chronically raised above 139 mmHg. Fluid will pool in the feet because of: a. a decrease in lymph b. an increase in oncotic pressure c. a decrease in total peripheral resistance (TPR) d. an increase in hydrostatic pressure

Answer 36

d. an increase in hydrostatic pressure

Question 37

Use the figure below to answer question 2:

As the heart rate increases from 70/min to 150/min, it is expected that the:

a. maximum membrane potential in phase 0 will increase.
b. duration of phase 2 will decrease.
c. duration of phase 1 will increase.
d. absolute refractory period will lengthen.

Answer 37

b. duration of phase 2 will decrease.

Question 38

Which is TRUE of the cardiac muscle cell action potential shown below?

a. Slow repolarization in Phase 3 is due to opening of the funny sodium channels
b. Phase 0 is caused by a rapid increase in sodium influx
c. Slow depolarization in phase 4 is due to sympathetic nerve stimulation
d. Phase 0 is caused by the opening of calcium channels

Answer 38

d. Phase 0 is caused by the opening of calcium channels

Question 39

In an electrocardiogram (ECG), the ventricular conduction time is denoted by:

a. P-wave duration
b. T-wave duration
c. QRS complex duration
d. PR interval

Answer 39

d. PR interval

Question 40

What is the ejection fraction for the left ventricle depicted in the P-V loop?

a. 100%
b. 80%
c. 60%
d. 50%

Answer 40

c. 60%