BIO 360 - Exam 3 - Chapter 15 Summary Questions

Question 1

Blood flow through the cardiovascular system is an excellent example of ______ ______ in the body. Cardiac contraction creates high pressure in the ventricles, and this pressure drives blood through the vessels of the systemic and pulmonary circuits, speeding up cell-to-cell ______. Resistance to flow is regulated by ______ and ______ ______ ______ that act on arteriolar smooth muscle and help match tissue perfusion to tissue needs.

What is the homeostatic baroreceptor reflex?

Capillary exchange of material between the plasma and interstitial fluid compartments uses several transport mechanisms, including ______, ______, and ______ ______.

Answer 1

mass flow / communication / local / reflex control mechanisms

monitors arterial pressure to ensure adequate perfusion of the brain and heart.

diffusion, transcytosis, bulk flow

Question 2

Homeostatic regulation of the cardiovascular system is aimed at?

Answer 2

maintaining adequate blood flow to the brain and heart.

Question 3

Total blood flow at any level of the circulation is equal to the ______ ______.

Answer 3

cardiac output

Question 4

Blood vessels are composed of layers of smooth muscle, elastic and fibrous connective tissue, and ______.

Answer 4

endothelium

Question 5

______ ______ ______ maintains a state of muscle tone.

Answer 5

Vascular smooth muscle

Question 6

The walls of the aorta and major arteries are both stiff and springy. This property allows them to?

AE

Answer 6

absorb energy and release it through elastic recoil

Question 7

______ regulate blood flow through capillaries by contraction and dilation of p______ s______.

Answer 7

Metarterioles / precapillary sphincters.

Question 8

______ and ______ ______ are the site of exchange between blood and interstitial fluid.

Answer 8

Capillaries / postcapillary venules

Question 9

______ hold more than half of the blood in the circulatory system. Why?

Answer 9

Veins / Veins have thinner walls with less elastic tissue than arteries, so veins expand easily when they fill with blood.

Question 10

______ is the process by which new blood vessels grow and develop, especially after birth.

Answer 10

Angiogenesis

Question 11

The ventricles create high pressure that is the driving force for blood flow. The ______ and ______ act as a pressure reservoir during ______ ______.

Answer 11

aorta / arteries / ventricular relaxation

Question 12

Blood pressure is highest in the ______ and decreases as blood flows through the circulatory system. At rest, desirable ______ ______ is 120 mm Hg or less, and desirable ______ ______ is 80 mm Hg or less.

Answer 12

arteries / systolic pressure / diastolic pressure

Question 13

Pressure created by the ventricles can be felt as a ______ in the arteries. Pulse pressure equals..

Answer 13

pulse / systolic pressure minus diastolic pressure.

Question 14

Blood flow against gravity in the veins is assisted by what two things?

Answer 14

(1) one-way valves
(2) respiratory and skeletal muscle pumps

Question 15

Arterial blood pressure is indicative of the driving pressure for blood flow. Mean arterial pressure (MAP) is defined as

Answer 15

diastolic pressure +1/3 (systolic pressure - diastolic pressure)

Question 16

Arterial blood pressure is usually measured with a sphygmomanometer. Blood squeezing through a compressed artery makes ______ sounds.

Answer 16

Korotkoff

Question 17

Arterial pressure is a balance between ______ ______ and ______ ______, the resistance to blood flow offered by the arterioles.

Answer 17

cardiac output / peripheral resistance

Question 18

If blood volume ______, blood pressure ______. If blood volume ______, blood pressure ______.

Answer 18

increases / increases / decrease / decrease

Question 19

Venous blood volume can be shifted to the ______ if arterial blood pressure falls.

Answer 19

arteries

Question 20

Arterioles regulate their own blood flow through my______ a______.

What two things does vasoconstriction do?

Answer 20

myogenic autoregulation

(1) increases the resistance offered by an arteriole
(2) decreases the blood flow through the arteriole

Question 21

What is active hyperemia and reactive hyperemia?

Answer 21

Active hyperemia is a process in which increased blood flow accompanies increased metabolic activity.

Reactive hyperemia is an increase in tissue blood flow following a period of low perfusion.

Question 22

Most systemic arterioles are under ______ ______ control.
______ causes ______.
Decreased sympathetic stimulation causes ______.

Answer 22

tonic sympathetic / Norepinephrine / vasoconstriction / vasodilation

Question 23

Epinephrine binds to arteriolar ______ and causes ______.

Epinephrine on ______ found in the arterioles of the heart, liver, and skeletal muscle, causes ______.

Answer 23

a-receptors / vasoconstriction

b-receptors / vasodilation

Question 24

Changing the resistance of the arterioles affects ______ ______ ______ and alters blood flow through the arteriole.

Answer 24

mean arterial pressure

Question 25

The flow through individual arterioles depends on their resistance. How?

Answer 25

The higher the resistance in an arteriole, the lower the blood flow in that arteriole.

Question 26

The reflex control of blood pressure resides in the ______ ______. ______ in the carotid artery and the aorta monitor arterial blood pressure and trigger the ______ ______.

Answer 26

medulla oblongata / Baroreceptors / baroreceptor reflex.

Question 27

Efferent output from the medullary cardiovascular control center _________________.
Increased sympathetic activity _______________.

Increased parasympathetic activity _________________.

Increased sympathetic discharge at the arterioles ______ ______.

There is no significant parasympathetic control of arterioles.

Answer 27

goes to the heart and arterioles.

increases heart rate and force of contraction.

slows heart rate.

causes vasoconstriction.

Question 28

Cardiovascular function can be modulated by input from higher brain centers and from the respiratory control center of the medulla.

Question 29

The ______ ______ functions each time a person stands up. The decrease in blood pressure upon standing is known as o______ h______.

Answer 29

baroreceptor reflex / orthostatic hypotension

Question 30

Exchange of materials between the blood and the interstitial fluid occurs primarily by ______.

Answer 30

diffusion

Question 31

______ ______ have leaky junctions between cells but also transport material using transcytosis. Continuous capillaries with tight junctions form the ______- ______ ______.

Answer 31

Continuous capillaries / blood-brain barrier

Question 32

______ ______ have pores that allow large volumes of fluid to pass rapidly.

Answer 32

Fenestrated capillaries

Question 33

The velocity of blood flow through the capillaries is slow, allowing diffusion to go to equilibrium.

Question 34

The mass movement of fluid between the blood and the interstitial fluid is ______ ______. Fluid movement is called ______ if the direction of flow is out of the capillary and ______ if the flow is directed into the capillary.

Answer 34

bulk flow / filtration / absorption

Question 35

The osmotic pressure difference between plasma and interstitial fluid due to the presence of plasma proteins is the ______ ______ ______.

Answer 35

colloid osmotic pressure.

Question 36

About 3 liters of fluid filter out of the capillaries each day. The lymphatic system returns this fluid to the circulatory system.

Question 37

Lymph capillaries accumulate fluid, interstitial proteins, and particulate matter by bulk flow. Lymph flow depends on smooth muscle in vessel walls, one-way valves, and the skeletal muscle pump.

Question 38

What is edema?

Answer 38

The condition in which excess fluid accumulates in the interstitial space is called edema. Factors that disrupt the normal balance between capillary filtration and absorption cause edema.

Question 39

______ ______ is the leading cause of death in the United States. Risk factors predict the likelihood that a person will develop cardiovascular disease during her or his lifetime.

Answer 39

Cardiovascular disease

Question 40

______ is an inflammatory condition in which fatty deposits called plaques develop in arteries. If plaques are unstable, they may block the arteries by triggering blood clots.

Answer 40

Atherosclerosis

Question 41

______ is a significant risk factor for the development of cardiovascular disease.

Answer 41

Hypertension