Chapter 10 The Blood Vessels and Blood Pressure Questions

Question 1

In general, the parallel arrangement of the vascular system enables each organ to receive its separate arterial blood supply. (True or false?)

Answer 1

True

Question 2

More blood flows through the capillaries during cardiac systole than during diastole. (True or false?)

Answer 2

False

Question 3

The capillaries contain only 5% of the total blood volume at any point in time. (True or false?)

Answer 3

True

Question 4

The same volume of blood passes through the capillaries in a minute as passes through the aorta, even though blood flow is much slower in the capillaries. (True or false?)

Answer 4

True

Question 5

Because capillary walls have no carrier transport systems, all capillaries are equally permeable. (True or false?)

Answer 5

False

Question 6

Because of gravitational effects, venous pressure in the lower extremities is greater when a person is standing up than when the person is lying down. (True or false?)

Answer 6

True

Question 7

• ____________ is a measure of the hindrance to blood ow through a vessel caused by friction between the moving fluid and the stationary vascular walls.

Answer 7

• Resistance is a measure of the hindrance to blood ow through a vessel caused by friction between the moving fluid and the stationary vascular walls.

Question 8

• Local mechanisms that keep tissue blood ow fairly constant despite wide deviations in mean arterial driving pressure is termed __________.

Answer 8

• Local mechanisms that keep tissue blood ow fairly constant despite wide deviations in mean arterial driving pressure is termed autoregulation.

Question 9

• __________ refers to the volume of blood per unit of time flowing through a given segment of the circulatory system, whereas __________ is the speed, or distance per unit of time, with which the blood flows forward through a given segment of the circulatory system.

Answer 9

• Flow rate refers to the volume of blood per unit of time flowing through a given segment of the circulatory system, whereas velocity of flow is the speed, or distance per unit of time, with which the blood flows forward through a given segment of the circulatory system.

Question 10

• ________ is the term applied to vessel narrowing that increases resistance to flow, whereas ________ is the term applied to vessel widening that decreases resistance to flow.

Answer 10

• Vasoconstriction is the term applied to vessel narrowing that increases resistance to flow, whereas vasodilation is the term applied to vessel widening that decreases resistance to flow.

Question 11

Which of the following functions is or are attributable to arterioles? (Indicate all correct answers.)

Answer 11

a, c, d, e, f

Question 12

Using the answer code on the right, indicate whether the following factors increase or decrease venous return:

Answer 12

1.a, 2.a, 3.b, 4.a, 5.b, 6.a

Question 13

Compare blood flow through reconditioning organs and through organs that do not recondition the blood.

Answer 13

Question 14

Discuss the relationships among flow rate, pressure gradient, and vascular resistance.

What is the major determinant of resistance to flow?

Answer 14

Question 15

Describe the structure and major functions of each segment of the vascular tree.

Answer 15

Question 16

How do the arteries serve as a pressure reservoir?

Answer 16

Question 17

Describe the indirect technique of measuring arterial blood pressure by means of a sphygmomanometer.

Answer 17

Question 18

Compare the consequences of vasoconstriction and vasodilation each on distribution of cardiac output and on control of mean arterial blood pressure.

Answer 18

Mean arterial pressure shows the average blood pressure of an individual during single cardiac cycle.

Cardiac output shows the volume of blood pumped by heart from left ventricle to right ventricle at per unit of time. It can be calculated using the product of Heart rate and stroke volume

Vasoconstriction is the phenomenon of narrowing the blood vessel which causes the contraction of muscular wall of vessels in large and small arteries. This process is opposite of the vasodilatation. Narrowing of the arteries decrease or reduce the blood flow which causes the pale color of skin. It helps in maintaining the mean arterial pressure. Vasoconstriction occurs because of increase in concentration of calcium n vascular smooth muscle cells. Secondly Hormonal components plays similar role in vasoconstriction.

Vasodilatation is the method of widening the blood vessel in which smooth muscle cell get relaxed. It helps in the enlargement of the veins and arteries. Blood flow increases because blood vessel gets dilate and no resistance against flow rate. It decreases the blood pressure. It directly affects the cardiac output total peripheral resistance and mean arterial pressure.

So It concluded from above two methods i.e. vasoconstriction and vasodilatation that the size of blood vessel/vein effect the rate of blood flow which is directly connected with cardiac output and mean arterial blood pressure.

Question 19

Discuss the local and extrinsic controls that regulate arteriolar resistance.

Answer 19

Question 20

• What is the primary means by which individual solutes are exchanged across capillary walls?
• What forces produce bulk flow across capillary walls?
• Of what importance is bulk flow?

Answer 20

Question 21

How is lymph formed?

What are the functions of the lymphatic system?

Answer 21

Question 22

Define edema, and discuss its possible causes.

Answer 22

Question 23

How do veins serve as a blood reservoir?

Answer 23

Question 24

Compare the effect of vasoconstriction on the rate of blood flow in arterioles and in veins.

Answer 24

Question 25

Discuss the factors that determine mean arterial pressure.

Answer 25

Question 26

Review the effects on the cardiovascular system of

parasympathetic and sympathetic stimulation.

Answer 26

Question 27

Differentiate between secondary hypertension and primary hypertension.

What are the potential consequences of hypertension?

Answer 27

Question 28

Define circulatory shock.

What are its consequences and compensations?

What is irreversible shock?

Answer 28