Deck 14: The Cardiovascular System: Blood Vessels, Blood Flow, and Blood Pressure

Question 1

The total cross -sectional area is greatest in which blood vessels?

A) capillaries
B) venules
C) arterioles
D) arteries
E) veins

Answer 1

A

Question 2

What is/are the component(s) of a blood vessel's extracellular matrix that provide(s) the tensile strength required to withstand pressure?

A) hemoglobin
B) elastin
C) albumin
D) gap junctions
E) collagen

Answer 2

E

Question 3

The contractile activity of smooth muscle cells within which type of blood vessel is primarily involved in the control of the organ blood flow and mean arterial pressure?

A) capillaries
B) veins
C) venules
D) arterioles
E) arteries

Answer 3

D

Question 4

The elastic nature of the largest blood vessel's walls allows them to act as a the driving force for blood flow while the heart is relaxed during diastole.

A) contractile force
B) pressure reservoir
C) non -compliant structure
D) volume reservoir
E) non -distensible structure

Question 5

Which of the following is NOT a component of the microcirculation?

A) metarterioles
B) arterioles
C) venules
D) veins
E) capillaries

Question 6

What component of artery walls allows them to store energy that is later used to maintain continuous blood flow through the circulatory system?

A) smooth muscle
B) elastin
C) collagen
D) skeletal muscle
E) endothelium

Question 7

Blood pressure is usually estimated from indirect measurements of the pressure in what structure?

A) aorta
B) radial artery
C) brachial artery
D) femoral artery
E) left ventricle

Question 8

What is the driving force for blood flow through the systemic circuit?

A) left ventricular pressure
B) right atrial pressure
C) mean arterial pressure
D) capillary hydrostatic pressure
E) central venous pressure

Question 9

Resistance to blood flow is regulated primarily by what blood vessels?

A) capillaries
B) ventricle
C) arterioles
D) arteries
E) veins

Question 10

A person goes to the doctor and is told his blood pressure is 90/60 and his pulse is 80. Which of the following is FALSE?

A) Mean arterial pressure is 70 mm Hg.
B) Pulse pressure is 80 mm Hg.
C) Diastolic pressure is 60.
D) Systolic pressure is 90 mm Hg.
E) Heart rate is 80.

Question 11

The blood vessels of largest diameter are the , and the blood vessels with the thickest walls are the .

A) arteries : veins
B) arteries : arteries
C) veins : arteries
D) veins : veins
E) arteries : arterioles

Question 12

The lumen of every blood vessel is lined by a monolayer of what cell type?

A) platelets
B) fibroblasts
C) endothelial cells
D) erythrocytes
E) smooth muscle cells

Question 13

Arteries have

A) low : low
B) high : high
C) low : high
D) zero : high
E) high : low

Question 14

In the circulatory system, the largest pressure drop occurs across which blood vessels?

A) venules
B) veins
C) arterioles
D) arteries
E) capillaries

Question 15

Which of the following equations is correct?

A) cardiac output = mean arterial pressure × total peripheral resistance
B) resistance = (length × radius⁴) / viscosity
C) cardiac output = stroke volume × heart rate
D) mean arterial pressure = resistance × viscosity
E) mean arterial pressure = cardiac output × stroke volume

Question 16

What is a measure of the change in vascular volume as pressure within the vessel is altered?

A) diffusibility
B) resistance
C) the pressure gradient
D) compliance
E) blood flow

Question 17

Which of the following would increase the rate of blood flow through a blood vessel?

A) decreased radius of the vessel
B) increased pressure of the blood entering the vessel
C) constriction of the blood vessel
D) increased viscosity of the blood
E) increased length of the vessel

Question 18

In comparison to the systemic circuit, the pulmonary circuit

A) has lower resistance to blood flow.
B) transports deoxygenated blood.
C) has an equal pressure gradient to drive blood flow.
D) has lower blood flow.
E) is under greater pressure.

Question 19

The pulsatile nature of blood pressure is greatest in which blood vessels?

A) veins
B) arteries
C) capillaries
D) venules
E) arterioles

Question 20

Which of the following equations correctly relates flow, pressure, and resistance?

A) flow = pressure + resistance
B) pressure = flow × resistance
C) flow = pressure -resistance
D) flow = pressure × resistance
E) resistance = flow × pressure

Question 21

Which of the following substances is secreted by endothelial cells and causes vasoconstriction?

A) oxygen
B) bradykinin
C) nitric oxide
D) adenosine
E) endothelin -1

Question 22

Which of the following is an important vasodilator in coronary arteries?

A) adenosine
B) endothelin -1
C) nitric oxide
D) bradykinin
E) oxygen

Question 23

Blood flow velocity is inversely proportional to the pooled surface area of a structure; therefore, it is greatest in the

A) veins : arteries
B) arterioles : veins and slowest in the _ _.
C) arteries : capillaries
D) capillaries : arteries
E) arteries : veins

Question 24

What is a decrease in tissue oxygen called?

A) hypoxia
B) hypoxemia
C) hyperoxia
D) hyperemia
E) ischemia

Question 25

Chemicals released by metabolically active cells will cause which of the following?

A) relaxation of arteriolar smooth muscle to increase blood flow
B) contraction of capillary smooth muscle to increase blood flow
C) contraction of arteriolar smooth muscle to increase blood flow
D) contraction of arteriolar smooth muscle to decrease blood flow
E) relaxation of capillary smooth muscle to decrease blood flow

Question 26

During exercise, which organs receive an increase in the proportion of cardiac output delivered to them?

A) skeletal muscle, heart, and skin
B) brain and heart
C) skeletal muscle, heart, and brain
D) skeletal muscle, skin, and brain
E) gastrointestinal tract and skeletal muscle

Question 27

Any change in the relative distribution of cardiac output to an organ is typically due to changes in which of the following?

A) central venous pressure
B) mean arterial pressure
C) resistance of that organ's vascular bed
D) compliance of that organ's vascular bed
E) viscosity of the blood moving through that organ's vascular bed

Question 28

Which of the following statements about smooth muscle in arterioles is FALSE?

A) Muscle contraction is under intrinsic controls.
B) The muscle is multi -unit smooth muscle.
C) The muscle has inherent (myogenic) tone.
D) Muscle contraction is under extrinsic controls.
E) The muscle forms rings around the arteriole.

Question 29

An increase in the concentration of which of the following within the interstitial space surrounding an arteriole would cause that vessel to constrict?

A) prostacyclin
B) nitric oxide
C) oxygen
D) adenosine
E) lactic acid

Question 30

During exercise, which of the following tissues receive less blood flow compared to resting conditions?

A) gastrointestinal tract only
B) brain only
C) skin only
D) heart only
E) both gastrointestinal tract and skin

Question 31

Which of the following accurately compares active hyperemia to reactive hyperemia?

A) One is an intrinsic response, the other an extrinsic response.
B) One involves vasodilation, the other vasoconstriction.
C) One is caused by increased metabolic activity, the other in response to an increase in metabolites from an occlusion to blood flow.
D) One is an increase in blood flow, the other is a decrease.
E) One is caused by an increase in metabolites, the other to a decrease in perfusion pressure.

Question 32

Which of the following would decrease mean arterial pressure?

A) increase in total peripheral resistance
B) increase in arteriole diameter
C) increase in venous return
D) increase in heart rate
E) increase in stroke volume

Question 33

What is an increase in blood flow in response to an increase in tissue metabolic activity called?

A) ischemia
B) hypoxia
C) reactive hyperemia
D) active hyperemia
E) hyperoxia

Question 34

Which of the following chemicals' concentration is NOT increased by an elevation in metabolic activity?

A) potassium
B) oxygen
C) hydrogen
D) pyruvic acid
E) carbon dioxide

Question 35

What type of adrenergic receptor is found in the smooth muscle of most systemic arterioles?

A) alpha only
B) beta₁ only
C) beta₂ only
D) beta₃ only
E) both alpha and beta₁

Question 36

A decrease in pressure within an arteriole will initiate a(n)

A) arterial baroreceptor reflex.
B) active hyperemia.
C) sinus arrhythmia.
D) myogenic response.
E) cardiac and venous baroreceptor reflex.

Question 37

In response to a decrease in tissue metabolic activity, tissue oxygen concentrations , which causes a(n) .

A) increase : active hyperemic response
B) decrease : increase in tissue ischemia
C) decrease : dilation of the arterioles
D) decrease : active hyperemic response
E) increase : constriction of the arterioles

Question 38

What is the purpose of extrinsic control of arteriolar smooth muscle contractile activity?

A) regulate cardiac output
B) regulate blood flow through specific capillary beds
C) regulate mean arterial pressure
D) regulate heart rate
E) regulate stroke volume

Question 39

Which of the following substances is continuously secreted by endothelial cells and causes vasodilation?

A) oxygen
B) bradykinin
C) endothelin -1
D) adenosine
E) nitric oxide

Question 40

The effects of epinephrine on vascular resistance are dependent upon which of the following?

A) direction of change in mean arterial pressure
B) concentration of local metabolites
C) relative distribution of alpha and beta receptors
D) specific baroreceptor activated (low or high pressure)
E) relative distribution of nicotinic and muscarinic receptors

Question 41

describes the movement of fluid out of the capillary, while
Describes the
Movement of fluid into the capillary.

A) Filtration : absorption
B) Absorption : filtration
C) Venous pooling : edema
D) Hydrostatic pressure : oncotic pressure
E) Edema : venous pooling

Question 42

Drugs that block angiotensin -converting enzyme would cause which of the following?

A) activation of the parasympathetic nervous system
B) decreased heart rate
C) stimulation of reactive hyperemia
D) decreased mean arterial pressure
E) decrease in epinephrine release

Question 43

What region of the cardiovascular system contains valves?

A) heart only
B) metarterioles only
C) veins only
D) both the heart and veins
E) the heart, metarterioles, and veins

Question 44

Which of the following is NOT a mechanism that enables molecules to move across capillary endothelial cells?

A) diffusion of lipid -soluble molecules directly across the endothelial cell
B) movement of exchangeable proteins across endothelial cells
C) rapid diffusion of water -soluble molecules directly across the endothelial cells
D) movement through water -filled gaps between endothelial cells
E) transcytosis across endothelial cells

Question 45

Glucose moves across continuous capillary walls by what mechanism?

A) secondary active transport
B) transcytosis
C) diffusion
D) primary active transport
E) facilitated

Question 46

Which of the following is NOT a mechanism that alters the balance between filtration and absorption in the body?

A) increasing capillary hydrostatic pressure within the feet as one stands
B) increasing hydrostatic pressure gradient in cases of enhanced interstitial protein
C) increasing the elimination of plasma proteins in cases of kidney damage
D) increasing the permeability of the capillaries in regions of tissue damage
E) decreasing plasma protein synthesis in cases of liver damage

Question 47

Arteriolar smooth muscle in which of the following tissues tends to have beta₂ receptors predominating?

A) liver
B) skin
C) brain
D) gastrointestinal tract
E) skeletal muscle

Question 48

Veins functions as

A) volume : high
B) volume : low
C) pressure : high
D) pressure : low
E) pressure : lack of

Question 49

Exchange between blood and interstitial fluid occurs across capillaries and, to a lesser extent,

A) arterioles.
B) venules.
C) arteries.
D) veins.
E) metarterioles.

Question 50

What organ has capillaries that are the most restrictive to movement of hydrophilic solutes?

A) skeletal muscle
B) bone marrow
C) liver
D) brain
E) kidneys

Question 51

Which of the following comparisons between systemic capillaries and lymphatic capillaries is TRUE?

A) Net filtration occurs across systemic capillaries; net absorption occurs across lymphatic capillaries.
B) Walls of systemic capillaries are more permeable.
C) Fluid enters systemic capillaries from systemic arterioles; fluid enters lymphatic capillaries from lymphatic veins.
D) Pressure is higher in lymphatic capillaries.
E) Blood cells are found in both types of capillaries.

Question 52

Given that the net filtration of fluid out of the capillaries averages about 3 liters per day, how is blood volume maintained in light of this apparent fluid loss?

A) The lymphatic system returns filtered fluid to the blood.
B) The net filtration is equally balanced by absorption.
C) The kidneys are involved in the reabsorption of the remaining fluid.
D) Gravity moves the fluid to the lowest point in the body, where the fluid is absorbed.
E) While fluid moves out across the capillary, it tends to move inward across veins.

Question 53

Fenestrated capillaries are unique in their ability to

A) restrict the passage of proteins across endothelial cells.
B) allow relatively large molecules to pass between endothelial cells.
C) maintain a low permeability to small water -soluble molecules.
D) allow few molecules to pass between endothelial cells.
E) move molecules across endothelial cells by transcytosis.

Question 54

Which of the following would increase blood flow through a capillary bed?

A) constriction of the arteriole leading into the capillary bed
B) increase in venous pressure
C) contraction of smooth muscle in the metarterioles bypassing the capillary bed
D) contraction of precapillary sphincters in the capillary bed
E) decrease in blood pressure in the arteriole leading into the capillary bed

Question 55

Which of the following inaccurately represents normal forces across capillary walls?

A) Interstitial fluid oncotic pressure is almost zero.
B) Interstitial fluid hydrostatic pressure increases from arteriole end to venous end.
C) At rest, net filtration occurs across capillary walls.
D) Capillary hydrostatic pressure decreases from arteriole end to venous end.
E) Capillary oncotic pressure is due primarily to plasma proteins.

Question 56

The portion of osmotic pressure exerted by pressure (or oncotic pressure). in the blood is known as colloid osmotic

A) proteins
B) steroids
C) lipids
D) small ions
E) large ions

Question 57

Under normal conditions, which Starling forces favor filtration?

A) interstitial fluid hydrostatic pressure and plasma oncotic pressure
B) capillary hydrostatic pressure and plasma oncotic pressure
C) interstitial fluid hydrostatic pressure and interstitial fluid osmotic pressure
D) capillary hydrostatic pressure and interstitial fluid hydrostatic pressure
E) capillary hydrostatic pressure and interstitial fluid osmotic pressure

Question 58

In cardiac and skeletal muscle vasculature, the distribution of alpha and beta receptors is such that epinephrine will

A) increase skeletal muscle contractility.
B) induce a constriction that decreases blood flow to these tissues.
C) induce a dilation that increases blood flow to these tissues.
D) increase myocardial contractility.
E) have no effect on peripheral resistance.

Question 59

Which of the following would cause relaxation of precapillary sphincters?

A) epinephrine
B) carbon dioxide
C) sympathetic activity
D) vasopressin
E) parasympathetic activity

Question 60

Foreign materials are filtered out of the lymphatic fluid by what type of cell located within the lymph nodes?

A) mast cells
B) leukocytes
C) macrophages
D) erythrocytes
E) platelets

Question 61

The high compliance of veins allows them to

A) act as pressure reservoirs.
B) provide the driving force for the movement of blood through the vasculature during diastole.
C) rapidly change central venous pressure with small changes in blood volume.
D) accommodate large volumes of blood with little change in pressure.
E) hold only small volumes of blood.

Question 62

Which of the following descriptions of the autonomic innervation of the cardiovascular system is FALSE?

A) Both sympathetic and parasympathetic neurons innervate the SA node.
B) Sympathetic activity increases cardiac output, whereas parasympathetic activity decreases cardiac output.
C) Only sympathetic neurons provide significant innervation of the contractile cells of the heart.
D) Both sympathetic and parasympathetic neurons innervate smooth muscle in arterioles.
E) Only sympathetic neurons innervate smooth muscle in veins.

Question 63

The respiratory pump facilitates the return of blood to the heart by

A) decreasing the pressure gradient between abdominal and thoracic veins during inspiration.
B) raising the pressure gradient between abdominal and thoracic veins during inspiration.
C) raising the pressure gradient between abdominal and thoracic veins during expiration.
D) decreasing the pressure gradient between abdominal and thoracic veins during expiration.
E) squeezing blood from the rhythmic contraction of the diaphragm muscle.

Question 64

Information about mean arterial pressure is integrated within what area of the central nervous system?

A) medulla oblongata
B) cerebellum
C) pons
D) hypothalamus
E) cervical spinal cord

Question 65

Which of the following best classifies the baroreceptor reflex?

A) cranial; autonomic; innate; polysynaptic
B) cranial; somatic; conditioned; polysynaptic
C) spinal; autonomic; innate; polysynaptic
D) spinal; autonomic; innate; monosynaptic
E) cranial; autonomic; conditioned; monosynaptic

Question 66

Valves, which are found , maintain the unidirectional movement of blood, thereby facilitating the return of blood to the heart.

A) in all veins
B) only in arteries
C) only in central veins
D) only in peripheral veins
E) in all venules

Question 67

The reduction in organ blood flow that results from a decrease in mean arterial pressure would be exacerbated by the that occurs as a consequence of the baroreceptor reflex.

A) increased stroke volume
B) decreased compliance of the veins
C) increased ventricular contractility
D) increased venous return
E) increased peripheral resistance

Question 68

An increase in the volume of blood ejected from the heart, with no change in total peripheral resistance, would

A) reduce mean arterial pressure.
B) elevate pulmonary venous pressure.
C) elevate mean arterial pressure.
D) elevate central venous pressure.
E) reduce the stretch on the aorta.

Question 69

are responsible for the detection of mean arterial pressure.

A) Thermoreceptors
B) Medullary chemoreceptors
C) Arterial baroreceptors
D) Venous baroreceptors
E) Aortic chemoreceptors

Question 70

An increase in total peripheral resistance, in the absence of any change in cardiac output, would

A) reduce the stretch on the aorta.
B) reduce mean arterial pressure.
C) decrease pulmonary venous pressure.
D) elevate mean arterial pressure.
E) decrease central venous pressure.

Question 71

The chronic elevation in arterial pressure (hypertension) that occurs in many individuals results in

A) a decreased sensitivity of the baroreceptor that causes pressure to fluctuate.
B) the resetting of the baroreceptor to a lower pressure.
C) a gradual increase in pressure that resets the baroreceptors.
D) the maintenance of a constant error signal by the baroreceptor.
E) the baroreceptors becoming more sensitive to pressure.

Question 72

At rest, the greatest proportion of blood volume is present within the

A) systemic capillaries.
B) heart.
C) systemic arteries.
D) systemic veins.
E) pulmonary veins.

Question 73

Which of the following is NOT altered within seconds to minutes of the baroreceptor reflex being activated?

A) venomotor tone
B) heart rate
C) total peripheral resistance
D) blood volume
E) stroke volume

Question 74

Where is the cardiovascular control center?

A) adrenal cortex
B) hypothalamus
C) adrenal medulla
D) medulla oblongata
E) pons

Question 75

As mean arterial pressure increases, the pressure has indeed increased. , informing the medulla oblongata that blood

A) number of neurons stimulated within the aortic arch increases
B) number of sympathetic neurons activated decreases
C) amplitude of the action potentials from the baroreceptors increases
D) frequency of action potentials from the baroreceptors increases
E) blood flow to the brain increases

Question 76

Which of the following would NOT increase mean arterial pressure?

A) decreased parasympathetic activity effects on the heart
B) decreased parasympathetic activity effects on the arterioles
C) increased sympathetic activity to the heart
D) increased levels of epinephrine in the blood
E) increased sympathetic activity to the veins

Question 77

Which of the following does NOT occur in response to baroreceptors detecting an increase in mean arterial pressure?

A) decreased end -diastolic volume
B) decreased heart rate
C) vasoconstriction
D) decreased venous compliance
E) decreased frequency of sinoatrial node action potentials

Question 78

The long -term regulation of arterial blood pressure involves the

A) immediate change in activity of the nervous system.
B) control of peripheral resistance.
C) release of hormones over a period of minutes.
D) control of blood volume by the kidneys.
E) stimulation of an increase in urine flow through the kidneys.

Question 79

Which of the following will NOT occur in response to a decrease in the extent of stretch detected by a baroreceptor?

A) increased heart rate
B) increased urine flow
C) increased peripheral resistance
D) increased ventricular contractility
E) increased venomotor tone

Question 80

Which of the following would decrease central venous pressure?

A) increased blood volume
B) increased respiratory activity
C) activity of skeletal muscles
D) increased sympathetic activity
E) standing up