Circulatory System Flashcards

1
Q

What are the four functions of the circulatory system?

A
  1. Movement of fluids
  2. Regulation of temperature
  3. Distribution of molecules (hormones)
  4. Distribution of cells (immune system)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

There are two functional components to the cardiovascular system. What are they?

A
  1. The blood vascular system
  2. The lymphatic vascular system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the primary differences between the blood and lymphatic vascular systems?

A

The blood vascular system circulates blood vessels that are pumped by a muscular organ, the heart

The lymphatic vascular system returns and transports lymph without a central pump; smooth muscle in vessel walls move lymph in one direction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe the common structure of blood vessels.

A
  1. Tunica intima - inner lining with single layer of flattened epithelial cells (endothelium)
  2. Tunica media - middle layer, mostly muscular
  3. Tunica adventitia - outer layer of supporting tissue
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are vasa vasorum?

A

Small arteries that run in the tunica adventitia and send arterioles and capillaries into the tunica media to provide nutrient and waste exchange

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are vasa vasorum important?

A

Diffusion from the lumen is insufficient to provide the tunica media with nutrition and waste elimination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

________________ content exhibits the greatest variation from one part of the blood vascular system to the next

A

Muscle content

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is blood flow influenced by?

A

By variation in the activity of muscle tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Is there muscle in capillaries?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Is there muscle in the heart?

A

Yes, it’s literally all muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

The ____________________ is located anterior to the chest wall and connects to the great veins and artiers; it has a free apex and sits in the pericardial sac

A

Heart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the four histological characteristics of cardiac muscle tissue?

A

Small

Mononucleated

Branched

Intercalated discs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the four muscular chambers of the heart?

A

Left atria

Right atria

Left ventricle

Right ventricle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

The ________________ pump blood to the lungers and the body; the __________________ received blood from the lungs and the body

A

Ventricles

Atria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Walls of all four heart chambers consist of three major walls or tunics. What are they?

A
  1. Endocardium
  2. Myocardium
  3. Epicardium
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

The _________________________ is a single layer of squamous endothelial cells that sits on a thin layer of loose connective tissue that contains _______________ and collagen fivers and _____________ muscle cells

A

Endocardium

Elastic

Smooth muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

The ______________________ is below the endocardium and connects with the myocardium; it contains small vessels, nerves, and importantly ________________ _____________

A

Subendocardium

Purkinjie Fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

The ___________________ is the thickest of tunics in the heart and consists of _________________ muscle cells; it is much thicker in the ventricles than in the atria

A

Myocardium

Cardiac muscle cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Why does the myocardium have an extensive capillary network?

A

The high oxygen demand of the myocardium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

The ___________________ is the external layer of the heart and is composed of a simple squamous epithelium (_____________________) and supported by a thin layer of connective tissue

A

Epicardium

Mesothelium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

The thin layer of connective tissue that supports the epicardium is composed of ____________________ tissue containing _________________ fibers

A

Fibrocollagenous tissue

Elastic fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are papillary muscles?

A

Attachments for chordae tendinae (AV valves)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Myocardial thickness differs in individuals who are healthy or diseased; _____________________ results from long-standing physical exertion (athletes) and pathology (i.e., hypertension)

A

Hypertrophy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Muscle fivers are thicker and the nuclei are ________________ and _______________ in hypertrophied myocardium

A

Larger

Darker

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

The impulse-conducting system of the heart is responsible for what?

A

Generating the stimulus for contraction and spreading the contraction to the myocardium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are the three major components of the cardiac conducting system?

A
  1. Sinoatrial node
  2. Atrioventricular node
  3. Atrioventricular bundle of His
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Cells and fibers of the impulse-conducting system are modificed cardiac muscle cells functionally integrated by ____________ _____________

A

Gap junctions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

The impulse rate of the conducting system is controlled by the __________________ nervous system

A

Autonomic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Describe the steps of the impulse-conducting system of the heart.

A
  1. The SA node in the right atrium generates the impulse
  2. The impulse spreads to the AV node in the right atrium
  3. The impulse is passed along the conducting fibers of the AV bundle of His, which divide into the left and right bundle branches that become the Purkinjie Fibers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are the steps of the impulse conducting system?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

The atrioventricular bundle of His splits into the left and right _______________ _____________ that become the ______________ ___________ that run beneath the endocardium and penetrate the myocardium

A

Bundle branches

Purkinjie fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

The bundle branches are separated from myocardial fibers by a ______________ layer; they are specialized conducting fibers that contain few myofibrils and abundant ________________ granules and _______________

A

Fibrous

Glycogen

Mitochondria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

_______________ _________________ are the terminal branches of the AV bundle branches located in the subendocardial connective tissue

A

Purkinjie fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What are the histological and structural characteristics of Purkinjie fibers?

A

Purkinjie fibers are large modified cardiac muscle fibers that cluster together in groups with one to two nuclei per cell

They contain a pale-staining central area with red stains on the cell periphery representative of myofibrils

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Do Purkinjie fiber contain T-tubules and intercalated discs? If not, how do they communicate and connect with each other?

A

No, they are connected by desmosomes and gap junctions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

The heart has four valves. What are they?

A
  1. The mitral valve
  2. The tricuspid valve
  3. The aortic valve
  4. The pulmonary valve
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

The mitral and tricuspid valves control blood flow from the ______________ to the _____________

A

Atria

Ventricles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

The aortic and pulmonary valves control blood flow out of the _________________

A

Ventricles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

______________ ______________ can be thought of as double-sided flattenings of the basic cardiovascular histological layers with different histological profiles to match their different physiological roles

A

Heart valves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What are the specialized features of heart valves?

A

They are primarily composed of a tough, specialized tunica intima in the absence of other vascular layers; the endothelium is continuyous with that of the cardiac wall while the collagenous layer toughens and becomes highly fibrous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Heart valves are primarily composed of a tough, specialized ______________ ____________ in the absence of other vascular layers; the ______________is continuous with that of the cardiac wall while the _______________ layer toughens and becomes highly ________________

A

Tunica intima

Endothelium

Collagenous

Fibrous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Identify the blood vessel tunic:

–1 layer endothelial cells

–Supported by subendothelial CT layer (Loose CT) with occasional smooth muscle cells

A

Tunica intima

43
Q

What do the tunicas intimas of the arteries have that those of veins?

A

In arteries, the internal elastic lamina separates the intima from the media

44
Q

Identify the tunic of the blood vessel:

–Middle layer

–Concentric layers of smooth muscle cells

A

Tunica media

45
Q

What do the tunica media of arteries contain that veins do not?

A

A thinner external elastic lamina that separates the media from the adventitia

46
Q

Identify the blood vessel tunic layer:

–Type 1 collagen and elastic fibers

–Gradually continuous with stromal CT of organ through which the vessel runs

A

Tunica adventitia

47
Q

Large vessels usually have ______________ _____________ or “vessel of the vessel” and a network of __________________ sympathetic nerve fibers to control _________________

A

Vasa vasorum

Unmyelinate

Vasoconstriction

48
Q

What is the function of the arterial system?

A

To distribute blood from heart to capillary beds throughout the body

49
Q

The pumping action of heart produces pulsatile blood flow in arterial system: the contraction of ventricles is known as ______________ (blood forced into arteries and arterial walls expand), and the recoil of the arterial walls is known as _____________

A

Systole

Diastole

50
Q

What regulates the flow of blood to organs and tissues?

A

The diameter of the distributing vessels

51
Q

The arterial system vessel walls conform to the general three-tunic structure but are characterized by increased ___________________ and a thicker ______________ _____________ wall relative to lumen diameter

A

Elastin

Smooth muscle

52
Q

There are three types of arterial vessels. What are they?

A

Elastic artery

Muscular artery

Arteriole

53
Q

The ______________ arteries are the major distribution vessels of the arterial system; they help stabilize blood flow and include the aorta, brachopephalic trunk, common cartoid artery, subclavian artery, and large pulmonary arteries

A

Elastic

54
Q

The tunica media of elastic arteries contain many _______________ fibers

A

Elastic fibers

55
Q

How is the tunica intima of elastic arteries different from those of muscular arteries?

A

The tunica intima of elastic arteries is much thicker than those of muscular arteries

56
Q

The aorta is a prime example of an elastic artery. The tunica intima is composed of a single layer of flattened endothelial cells that are supported by a layer of ___________________ tissue rich in _______________; its subendothelial supportive tissue contains _______________ and ________________ cells that are structurally similar to smooth muscle cells

A

Collagenous

Elastin

Fibroblasts

Myointimal cells

57
Q

The subendothelial layer in the elastic artery, the aorta, contains two cell types. What are they?

A

Fibroblasts

Myointimal cells (similar to smooth muscle cells)

58
Q

The _____________ ___________ of elastic arteries is broad and extremely elastic, and the ____________ _____________ of elastic arteries is collagenous with small vasa vasorum, which penetrate the outer half of the tunica media

A

Tunica media

Tunica adventitia

59
Q

_________________ arteries are the main distributing branches of the arterial tree

A

Muscular

60
Q

_______________ arteries have very thin intimas with adventitia layers of various thickness

A

Muscular

61
Q

Whereas elastic tissue is found nearly throughout elastic arteries, how is elastic tissue organized in muscular arteries?

A

Elastic tissue is concentrated into two well defined elastic sheets:

Internal elastic lamina (IEL) (between the intima and media)

External elastic lamina (EEL) (between media and adventitia)

62
Q

What are some examples of muscular arteries?

A

Radial

Femoral

Coronary

Cerebral

63
Q

Small muscular arteries have a thin but distinct _________________________ but little or no _____________________ while their medias contain three to 10 layers of smooth muscle with nearly no ________________ _______________

A

Internal elastic lamina

External elastic lamina

Elastic fibers

64
Q

____________________ contain only one to two layers of smooth muscle and are the primary site of vascular resistance

A

Arterioles

65
Q

Explain the flow of blood from aorta to capillary.

A

Elastic artery

Large muscular artery

Small muscular artery

Large arteriole

Small ateriole

Capillary

66
Q

As muscular arteries merge into larger arterioles and smaller arterioles, there is a gradual loss of the ______________ _______________ ______________ and a reduction in the number of ____________ ___________ in the ______________

A

Internal elastic lamina

Muscle layers

Media

67
Q

Larger arterioles have only __ to __ layers in their medias with very thin _______________ that are sometimes indistinguishable from the surrounding collagenous fibrous tissue

A

Two to three

Adventitia

68
Q

______________________ are thin-walled vessels forming interconnected networks for the exchange of gases, fluids, nutrients, and metabolic wastes

A

Capillaries

69
Q

How is the blood flow of capillaries regulated?

A

Via the arterioles and precapillary sphincters

70
Q

To what do capillaries drain into?

A

Postcapillary venules

Collecting venules

Small muscular venules

71
Q

What blood vessels are the only ones that permit exchange?

A

Capillaries

72
Q

There are two main types of capillaries. What are they?

A

Continuous

Fenestrated

73
Q

Flow in capillaries is by arterioles and muscular sphincters called ______________ ______________

A

Precapillary sphincters

74
Q

_______________ are composed of a single layer of endothelial cells rolled up in the form of a tube

A

Capillaries

75
Q

Thin walls and slow blood flow favors _____________ in capillaries

A

Exchange

76
Q

Does blood move fast or slow in capillaries?

A

Slow

77
Q

What are pericytes?

A

Pericytes are contractile cells that wrap around the endothelial cells of capillaries and venules that regulate capillary blood flow, the clearance and phagocytosis of cellular debris, and the permeability of the blood–brain barrier

78
Q

What are the functions of pericytes?

A

To regulate the flow of blood in capillaries, the clearance and phagocytosis of cellular debris, and the permeability of the blood-brain barrier

79
Q

Where are pericytes embedded?

A

The basement membrane

80
Q

How do pericytes communicate with endothelial cells?

A

Direct physical contact

Paracrine signaling

81
Q

Most regions of the body are supplied by ____________________ capillaries that contain a complete lining, where they regulate the exchange of material, and maintain a distinct continuity with endothelial cells

A

Continuous capillaries

82
Q

______________________ capillaries contain “windows” or pores that permit the rapid exchange of water and solutes

A

Fenestrated

83
Q

Where are fenestrated capillaries found?

A

In tissues where rapid interchange of substances occurs between the tissues and blood (e.g., kidney, intestine, choroid plexus, endocrine gland)

84
Q

The _______________ system of the cardiovascular system is the low pressure component that carries blood from capillaries back to the right atrium of the heart

A

Venuous

85
Q

How does blood flow against gravity in the venuous system?

A

Contractions of smooth muscle in vein walls and the external compression of veins by surrounding skeletal muscle

86
Q

How is backflow prevented in the venuous system?

A

The presence of valves

87
Q

Why is it important to move (in regards to the venuous system)?

A

Skeletal muscle compression of veins assists in blood flow

88
Q

While veins maintain the general three-layer structure of blood vessels, how do they differ from arteries?

A

They have less elastic and muscular components

89
Q

Which system contains a larger portion of blood: the arterial or venuous system?

A

Venuous

PV = nRT

(Less pressure = more volume)

90
Q

What are venules?

A

The smallest venous vessels that collect blood from capillary beds

91
Q

What is a characteristic feature of all venules?

A

Large diameter of the lumen compared to the overall thinness of the wall

92
Q

The transition from capillaries to _______________ occurs gradually and the immediate _______________ _______________ are structually similar to capillaries but with larger diameters

A

Venules

Postcapillary venules

93
Q

Postcapillary venules converge into larger __________________ _______________ that have more contracile cells

A

Collecting venules

94
Q

Venules become surrounded by recognizable tunica medias with two or three smooth muscle layers and are called __________________ venules

A

Muscular

95
Q

Blood entering veins is under very low _________________

A

Pressure

96
Q

How does blood move towards the heart in veins?

A

Via contraction of the tunica media and external compressions from surrounding muscles and organs

97
Q

______________ project from the tunica intima to prevent the back flow of blood

A

Valves

98
Q

Most veins are ____________ or _____________ veins and are usually located in parallel with corresponding muscular arteries

A

Small

Medium

99
Q

What are the primary differences between venules and veins?

A

Venules contain a clealy difined intimal layer but no elastic fibers; the tunica media contains one to two smooth muscle layers

Veins have a thicker muscular wall with poorly developed internal elastic lamina

100
Q

In ________________-sized veins the tunica intima is hard to discern and the tunica media is compared to an artery

A

Medium

101
Q

Medium-sized veins have two to four layers of smooth muscle fibers arranged circumferentially, and the ____________ _____________ is usually the thickest layer

A

Tunica adventitia

102
Q

_______________ veins are big venous trucks paired with elastic arteries close to the heart

A

Large

103
Q

Large veins have a well-developed tunica intima but a relatively thin _______________ ______________ with few layers of smooth muscle and abudant connective tissue

A

Tunica media

104
Q
A