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Human Anatomy > Unit 14 - The Heart > Flashcards

Unit 14 - The Heart Flashcards

1
Q

The continual circulation of blood throughout the body is essential for maintaining _____

A

Homeostasis (a state of equilibrium within the body)

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2
Q

In a healthy adult male, the heart beats about _____ per minute

A

75 times

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3
Q

The amount of blood pumped from one ventricle per minutes is called the

A

Cardiac Output

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4
Q

The heart can increase its output up to _______ when the body is more active, and the cells need oxygen and nutrients at a faster pace.

A

Five or six-fold

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5
Q

The “cardiovascular system” consists of the _______

A

Heart and Blood Vessels

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6
Q

There are two basic types of blood vessels, which are they

A

Arteries & Veins

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7
Q

These carry blood away from the heart

A

Arteries

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8
Q

These carry blood towards the heart

A

Veins

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9
Q

The arteries branch to form smaller _____

A

Arterioles

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10
Q

Most arteries carry blood high in ______

except for the pulmonary arteries

A

Oxygen

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11
Q

The veins branch to form smaller _____

A

Venules

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12
Q

Most veins carry blood low in _____

except for the pulmonary veins

A

Oxygen

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13
Q

The arteries and veins entering and leaving the heart are called the ______, because of their relatively large diameter

A

Great Vessels

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14
Q

The heart’s anatomy ensures the “______ flow” of blood through both the heart and blood vessels.

A

Unidirectional

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15
Q

Backflow of blood is prevented by ______ within the heart

A

Valves

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16
Q

The heart acts like two side-by-side pumps that work at the same rate, but with different amounts of force and pressure.

1) The ______ directs blood to the lungs for gas exchange.
2) The ______ directs blood to body tissues for nutrient and respiratory gas delivery

A
  1. Right Side

2. Left Side

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17
Q

The heart develops “______” through alternate cycles of heart wall contraction and relaxation

A

blood pressure

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18
Q

A minimum _______ is essential to push blood through blood vessels to the body tissues for nutrient and waste exchange

A

blood pressure

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19
Q

The cardiovascular system consists of two circulations, which are they

A

Pulmonary and systemic circulations

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20
Q

The “pulmonary circulation” consists of what

A

a. The chambers on the right side of the heart (right atrium and right ventricle)
b. “Pulmonary arteries”, which convey poorly oxygenated blood to the lungs to eliminate carbon dioxide and to replenish oxygen.
c. “Pulmonary veins”, which convey blood containing relatively low amounts of carbon dioxide and high amounts of oxygen from the lungs to the left side of the heart for pumping to the systemic circulation.

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21
Q

Convey poorly oxygenated blood to the lungs to

eliminate carbon dioxide and to replenish oxygen.

A

Pulmonary Arteries

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22
Q

convey blood containing relatively low amounts of carbon dioxide and high amounts of oxygen from the lungs to the left side of the heart for pumping to the systemic circulation.

A

Pulmonary Veins

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23
Q

The “systemic circulation” consists of what

A

(a) The chambers on the left side of the heart (left atrium and left ventricle).
(b) All the other named blood vessels that carry blood to all the peripheral organs and tissues of the body.

  • Blood that is high in oxygen (oxygenated) from the left side of the heart is
    pumped into the “aorta”, the largest systemic artery in the body, and then into
    smaller systemic arteries.
  • Gas exchange in tissues occurs from the body’s smallest vessels, called
    “capillaries”.
  • Systemic veins carry blood that is low in oxygen (deoxygenated) and high in
    carbon dioxide and waste products.
  • Most veins merge into the “superior vena cava” or into the “inferior vena cava”,
    both of which drain blood into the right atrium.
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24
Q

Blood that is high in oxygen (oxygenated) from the left side of the heart is pumped into the _____, the largest systemic artery in the body, and then into smaller systemic arteries.

A

Aorta

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25
Q

Gas exchange in tissues occurs from the body’s smallest vessels called ______

A

Capillaries

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26
Q

______ carry blood that is low in oxygen (deoxygenated) and high in carbon dioxide and waste products

A

Systemic Veins

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27
Q

Most veins merge into the _______, both of which drain blood into the right atrium.

A

“superior vena cava” or into the “inferior vena cava”

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28
Q

Where is the heart located?

A

The heart is located in the mediastinum left of the body midline and posterior to the sternum.

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29
Q

The heart is rotated such that its _________
is located more anteriorly, while its ________
is located more posteriorly

A

right side or border (right atrium and right ventricle)

left side or border (left atrium and left ventricle)

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30
Q

The posteriosuperior surface of the heart, formed primarily by the left atrium, is called the ____

A

“base”

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31
Q

What borders the base?

A

The pulmonary veins that enter the left atrium

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32
Q

The inferior, conical end of the heart is called the ______ and it projects slightly anterioinferiorly toward the left side of the body

A

“apex”

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33
Q

The heart is contained within the ______,

a fibrous sac and double-layered serous lining.

A

“pericardium”

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34
Q

The _______ restricts heart movements so that it doesn’t bounce and move about in the thoracic cavity, and prevents the heart from overfilling with blood.

A

“pericardium”

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35
Q

The pericardium is composed of two parts, what are they

A

Fibrous Pericardium & Serous Pericardium

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36
Q

The outer portion of the pericardium is a tough, dense connective tissue layer

A

Fibrous Pericardium

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37
Q

This layer is attached to both the diaphragm and the base of the great vessels.

A

Fibrous Pericardium

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38
Q

The inner portion of the pericardium is a thin, double-layered serous membrane

A

Serous Pericardium

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39
Q

The serous pericardium may be subdivided into two layers that are actually continuous with each other and reflect along and attach to the great vessels

A

Parietal Layer & Visceral Layer

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40
Q

The _____ of this serous membrane lines the inner surface of the fibrous pericardium.

A

“parietal layer”

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41
Q

The ______ of this serous membrane is fused to the outer surface of the heart

A

“visceral layer”

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42
Q

The visceral layer is also called the _____

A

Epicardium

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43
Q

The thin potential space between the parietal and visceral layers of the serous pericardium is called the ________

A

“pericardial cavity”

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44
Q

______ is secreted into the pericardial cavity in order to lubricate the membranes and facilitate the almost frictionless continuous movement of the heart when it beats.

A

Serous Fluid

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45
Q

Inflammation or bleeding into the pericardial cavity can lead to ______

A

“cardiac tamponade”

This life-threatening condition is characterized by “pulsus paradoxus”, “jugular vein distention” (JVD), and falling blood pressure

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46
Q

an inflammation of the pericardium, typically caused by viruses, bacteria, or fungi

A

Pericarditis

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47
Q

Pericarditis inflammation is associated with an increase in ______ of the capillaries, which become more “leaky,” resulting in fluid accumulation in the pericardial cavity

A

permeability

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48
Q

The heart is unable to pump blood, leading to a medical emergency called _______ and possibly resulting in heart failure and death

A

cardiac tamponade

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49
Q

A helpful physical finding in diagnosing pericarditis is _______, a crackling or scraping sound heard with a stethoscope that is caused by the movement of the inflamed pericardial layers against each other.

A

friction rub

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50
Q

The heart is a relatively small, conical organ approximately the size of a person’s _______

A

Clenched Fist

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51
Q

The heart wall consists of three distinctive layers, what are they

A

Epicardium, Myocardium, Endocardium

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52
Q

the outermost heart layer and is also

known as the visceral layer of the serous pericardium

A

Epicardium

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53
Q

the middle layer of the heart wall and is composed of cardiac muscle tissue

A

Myocardium

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54
Q

the thickest of the three heart wall layers

A

Myocardium

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55
Q

where “myocardial infarctions” (MIs or heart attacks)

occur.

A

Myocardium

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56
Q

The internal surface of the heart and the external surfaces of the heart valves are covered by ______

A

Endocardium

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57
Q

The endocardium is contiguous with the “________, the inner lining of the blood
vessels

A

endothelium

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58
Q

The heart is composed of four hollow chambers, what are they

A

1) Two smaller atria

2) Two larger ventricles

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59
Q

Are thin-walled chambers that are located superiorly

A

Atria

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60
Q

The anterior part of each atrium is a wrinkled, flap-like extension called an ______

A

Auricle

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61
Q

The atria receive blood returning to the heart through both circuits.

(a) The ____ atrium receives blood from the systemic circuit.
(b) The _____ atrium receives blood from the pulmonary circuit

A

Right

Left

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62
Q

Blood that enters an atrium is passed to the ventricle on the _____ side of the heart.

A

Same

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63
Q

the inferior chambers of the heart

A

Ventricles

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64
Q

Two large arteries exit the heart at the basal surface, what are they

A

The pulmonary trunk and aorta

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65
Q

carries blood from the right ventricle into the

pulmonary circuit

A

The pulmonary trunk

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66
Q

conducts blood from the left ventricle into the systemic circuit

A

Aorta

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67
Q

The valves, which are lined with _______, allow blood to only travel in one direction and prevent backflow.

A

endothelium

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68
Q

Is located between the atria and the ventricles, and is

formed from dense irregular connective tissue.

A

The “fibrous skeleton”

69
Q

The fibrous skeleton performs several important functions, what are they

A

(a) Separates the atria and ventricles.
(b) Anchors heart valves by forming supportive rings at their attachment points.
(c) Provides electrical insulation between atria and ventricles.
- This insulation ensures that the muscle impulses are NOT spread randomly
throughout the heart, and thus prevents all of the heart chambers from beating at
the same time.
(d) Provides a rigid framework for the attachment of cardiac muscle tissue.

70
Q

The “right atrium” receives venous blood from the ______ and from the heart muscle itself

A

systemic circulation

71
Q

The ______ drains blood from the head, neck, upper limbs, and the superior regions of the trunk.

A

superior vena cava

72
Q

The ______ drains blood from the lower limbs and trunk.

A

“inferior vena cava”

73
Q

The ______ drains blood from the heart wall.

A

“coronary sinus”

74
Q

The ______ forms a thin wall between the right and left atria.

A

“interatrial septum”

75
Q

There is an oval depression in the interatrial septum called the _______

A

“fossa ovalis”

76
Q

occupies the former location of the “foramen ovale” which shunted blood from the right atrium to the left atrium during fetal life

A

“fossa ovalis”

77
Q

Separating the right atrium form the right ventricle is the _______

A

“right atrioventricular (AV) valve” (also called the “tricuspid valve”, since it has three triangular flaps)

78
Q

Deoxygenated venous blood flows from the right atrium, through the _____, into the right ventricle.

A

right AV valve

79
Q

The right AV valve is forced closed when the _____ begins to contract, preventing backflow into the right atrium.

A

right ventricle

80
Q

The _______ receives deoxygenated venous blood from the right atrium

A

“right ventricle”

81
Q

An ______ forms a thick wall between the right and left ventricles

A

“interventricular septum”

82
Q

The internal wall surface of each ventricle displays characteristic large, smooth, irregular muscular ridges, called the _______

A

“trabeculae carneae”

83
Q

The _____ has three cone-shaped, muscular projections, called “papillary muscles”, which anchor thin strands of collagen fibers called “chordae tendineae”.

A

Right Ventricle

84
Q

The right ventricle has three cone-shaped, muscular projections, called _____

A

“papillary muscles”

85
Q

The Papillary muscles anchor thin strands of collagen fibers called ______

A

“chordae tendineae”

86
Q

Chordae tendineae attach to the lower surface of cusps of the _______ and prevent the valve from everting and flipping into the atrium when the right ventricle is contracting.

A

right AV valve

87
Q

At the superior end of the right ventricle is the ______, which marks the end of the right ventricle and the entrance into the pulmonary
trunk.

A

“pulmonary semilunar valve”

88
Q

The pulmonary trunk divides shortly into right and left ________, which carry deoxygenated blood to the lungs

A

“pulmonary arteries”

89
Q

______ are located within the walls of both ventricles immediately before connection of the ventricle to the pulmonary trunk and aorta.

A

Semilunar valves

90
Q

Each semilunar valve is composed of three thin, half-moon-shaped, pocket-like ________

A

Semilunar cusps

As blood is pumped into the arterial trunks, it pushes against the cusps, forcing the valves open

91
Q

Once gas exchange occurs in the lungs, the oxygenated blood (such blood is typically red) travels through the _____ to the left atrium.

A

pulmonary veins

92
Q

The smooth posterior wall of the left atrium contains openings for approximately ____ pulmonary veins.

  • Sometimes two of these vessels fuse prior to reaching the left atrium, thus
    decreasing the number of openings through the atrial wall.
A

Four

93
Q

Separating the left atrium from the left ventricle is the ______

A

“left atrioventricular (AV) valve” (also called the “bicuspid valve”, since it has two triangular cusps, or it may be called the “mitral valve”, since the two triangular cusps resemble a miter, the headpiece worn by a bishop).

94
Q

Oxygenated blood flows from the left atrium, through the ______, into the left ventricle.

A

left AV valve

95
Q

The ______ is forced closed when the left ventricle begins to contract, preventing blood backflow into the left atrium

A

left AV valve

96
Q

The left ventricle has a wall that is typically three times thicker than the right ventricular wall

A

True

97
Q

The left ventricle requires thick walls in order to generate enough pressure to force the oxygenated blood that has returned to the heart from the lungs into the aorta and then through the entire systemic circulation

A

True

98
Q

The trabeculae carneae in the left ventricle are more prominent than those in the right ventricle.

A

True

99
Q

Two large papillary muscles project from the ventricle’s inner wall and attach to the ____ that help support the left AV valve.

A

chordae tendineae

100
Q

At the superior end of the ventricular cavity, the ______” marks the end of the left ventricle and the entrance to the aorta

A

“aortic semilunar valve

101
Q

The “lubb” sound is also known as the S1 sound and represents _____

A

the closing of the atrioventricular valves

102
Q

The “dupp” sound is also known as the S2 sound and is _____

A

the closing of the semilunar valves

103
Q

An abnormal heart sound, generally called a ______, is the first indication of heart valve problems

A

heart murmur

104
Q

■The aortic semilunar valve is best heard in the second intercostal space to the right of the sternum.

■The pulmonary semilunar valve is best heard in the second intercostal space to the left of the sternum.

■The right AV valve is best heard at the inferior left sternal border in the fifth intercostal space.

■The left AV valve is best heard near the apex of the heart (at the level of the left fifth intercostal space, about 9 centimeters from the midline of the sternum).

A

Yes, true

105
Q

A heart murmur is usually the result of turbulence of the blood as it passes through the heart, and may be caused by what

A

valvular leakage, decreased valve flexibility, or a misshapen valve

106
Q

Two types of heart murmurs

A

valvular insufficiency and valvular stenosis

107
Q

Also termed valvular incompetence, occurs when one or more of the cardiac valves leaks because the valve cusps do not close tightly enough

A

Valvular insufficiency

108
Q

is scarring of the valve cusps so that they become rigid or partially fused and cannot completely open

Often the affected chamber undergoes hypertrophy and dilates

A

Valvular stenosis

109
Q

A primary cause of valvular stenosis is _____, which may follow a streptococcal infection of the throat

A

rheumatic heart disease

110
Q

________ travel in the atrioventricular groove between the atria and ventricles to supply the heart wall.

A

“Left and right coronary arteries”

111
Q

These arteries are the only branches of the ascending aorta.

A

“Left and right coronary arteries”

112
Q

They exit the ascending aorta immediately superior to the aortic semilunar valve.

A

“Left and right coronary arteries”

113
Q

The left and right coronary arteries branch into smaller arteries and arterioles to deliver oxygenated blood and nutrients ________ of the atria and ventricles.

A

to the capillaries of the myocardium

114
Q

Coronary arteries may become narrowed and occluded with plaques in a condition called _____

A

atherosclerosis or coronary artery disease

115
Q

sudden narrowing of the vessels caused by smooth muscle contraction in their wall

A

coronary spasm

116
Q

Either atherosclerosis or coronary spasm can lead to ______ or the more severe myocardial infarction.

A

angina pectoris

117
Q

a poorly localized pain sensation in the left side of the chest, the left arm and shoulder, or sometimes the jaw and the back

A

angina pectoris

it results from strenuous activity, when workload demands on the heart exceed the ability of the narrowed coronary vessels to supply blood

118
Q

The term _____ refers to death of tissue due to lack of blood supply.

A

infarction

119
Q

commonly called a heart attack, is a potentially lethal condition resulting from sudden and complete occlusion of a coronary artery.

A

Myocardial infarction (MI)

120
Q

is characterized by inadequate supply of

oxygen and blood to a part of the body

A

“Ischemia”

“Myocardial ischemia” can be painless (silent myocardial ischemia) or agonizing
(angina pectoris).

121
Q

Venous return occurs through one of several ____ that collect deoxygenated blood and wastes from the myocardial capillaries.

A

“cardiac veins”

122
Q

All of cardiac veins drain into the _______, a large vein that lies in the posterior aspect of the atrioventricular groove.

A

“coronary sinus”

123
Q

Because the ventricular myocardium is compressed during contraction (systole), most coronary flow occurs during _____, when ventricular walls are relaxed.

A

relaxation (diastole)

124
Q

a. Normally, flow is evenly distributed throughout the thickness of the myocardium.
b. Under certain circumstances, however, coronary flow may be reduced, especially to the regions immediately external to the endocardium.

A

True

125
Q

an abnormally increased heart rate
(greater than 100 beats per minute), shortens diastole and reduces blood flow to
the ventricular myocardium.

A

“Tachycardia”

126
Q

____, abnormally low blood pressure, can also reduce the ability of
blood to flow through the ventricular myocardium.

A

“Hypotension”

127
Q

contractions are made possible by the properties of cardiac muscle tissue and by specialized cells in the heart, known collectively as its

A

conducting system

128
Q 
The heart exhibits \_\_\_\_\_\_\_, meaning that the
heart itself (not external nerves) is responsible for initiating the heartbeat.
A

“autorhythmicity” or “intrinsic rhythmicity”

129
Q

The heartbeat is initiated by the cardiac fibers of the ______, which are located in the posterior wall of the right atrium, adjacent to the entrance of the superior vena cava

A

“sinoatrial (SA) node”

130
Q

The fibers of the _____ act as the “pacemaker”, the rhythmic center that establishes the pace for cardiac activity

A

SA node

131
Q

Under the influence of the parasympathetic innervation, SA node fibers initiate impulses _____ times per minute

A

70-80

132
Q

From the SA node the muscle impulses travel through cardiac muscle of both atria to cause contraction (atrial systole) and then to the _______”

A

“atrioventricular (AV) node”

133
Q

The AV node is located where

A

in the floor of the right atrium between the right AV valve and the coronary sinus

134
Q

the ______ insulates the atria from the ventricles to prevent random nerve impulses from spreading between the atria and the ventricles.

A

fibrous skeleton

135
Q

Thus, it is only through an opening in the fibrous skeleton that the muscle impulse can spread. This bundle is the atrioventricular bundle or the _____

A

“Bundle of His”.

136
Q

The muscle impulse then travels from the AV node to the ___________

A

“atrioventricular (AV) bundle”, also called the “Bundle of His”.

This bundle of conducting muscle fibers extends into the interventricular septum and then divides into one right bundle branch and two left bundle branches

137
Q

These bundle branches conduct the impulse to conduction fibers called ______ that begin within the apex of the heart and extend through the walls of the ventricles.

A

“Purkinje fibers”

Purkinje fibers are larger than other cardiac muscle fibers.

Muscle impulse conduction along the Purkinje fibers is extremely rapid, consistent with the large size of the cells, and the impulse spreads immediately throughout the ventricular myocardium, stimulating it to contract.

138
Q

The electrical activity of this conduction system, or more correctly, its effects on the myocardium, can be monitored with an __________

A

“electrocardiograph”, which generates an

“electrocardiogram” (ECG or EKG).

139
Q

The heart is innervated by the ______ nervous system

A

autonomic

140
Q

innervation of the heart consists of both sympathetic and parasympathetic components, collectively referred to as the _______

A

“coronary plexus”

The autonomic centers in the brainstem
don’t initiate a heartbeat, but they can increase or decrease the heartbeat

141
Q

“Sympathetic innervation” of the heart is carried out by nerve fibers from the ______ segments of
the spinal cord.

A

T1-T5

142
Q

Sympathetic innervation _____ the rate and force of heart contractions

A

increases

143
Q

“Parasympathetic innervation” comes from the ______

A

medulla oblongata via the left and right vagus nerves (CN X).

As the vagus nerves descend into the thoracic cavity they give off branches that supply the heart.

144
Q

Parasympathetic innervation ______ heart rate, but generally tends to have no effect on the force of contractions.

A

decreases

145
Q

the inclusive period of time from the start of one heartbeat to the initiation of the next.

A

A “cardiac cycle”

146
Q

The contraction of a heart chamber is called “_____”.

A

“systole”

During this period the contraction of the myocardium forces blood either into another chamber (from atrium to ventricle) or into a blood vessel (from a ventricle into the
attached larger artery).

147
Q

The relaxation phase of a heart chamber is termed _____

A

“diastole”.

During this period the myocardium of each chamber relaxes between contraction phases and the chamber fills with blood.

148
Q

At the beginning of the cardiac cycle _______ contract simultaneously.

A

the left and right atria

149
Q

When the atria contract (atrial systole) blood is forced into the ventricles through the ______

A

open AV valves.

During this time blood is still returning to the right atrium from the superior vena cava, the inferior vena cava, and the coronary sinus and to the left atrium from the pulmonary veins.

150
Q

After the atria begin to relax (atrial diastole), contraction of the ______ occurs simultaneously. Thus, only two of the four chambers (either atria or ventricles) contract at any one time.

A

left and right ventricles

151
Q

When the ventricles contract, the _______ close as blood is pushed against the cusps of the AV valves and their edges meet to form a seal.

A

atrioventricular valves

Papillary muscles and the chordae tendineae prevent these valve leaflets from everting.

The semilunar valves are forced open and blood enters the pulmonary trunk and the aorta

152
Q

When the ventricles are relaxing during the cardiac cycle (ventricular diastole) most of the blood flows passively from the relaxing atria into the ventricles through _______

A

open AV valves.

153
Q

For the last one-half of the cardiac cycle all four chambers of the heart are in _____ together

A

diastole

154
Q

any abnormality in the rate, regularity, or sequence of the cardiac cycle

A

Cardiac arrhythmia (also called dysrhythmia)

155
Q

occurs when the atria beat at 200 to 400 times per minute. Abnormal muscle impulses flow continuously through the atrial conduction system, thus stimulating the atrial musculature and AV node over and over.

A

Atrial flutter

156
Q

differs from atrial flutter in that the muscle impulses are significantly more chaotic, leading to an irregular heart rate. The ventricles respond by increasing and decreasing contraction activities, which may lead to serious disturbances in the cardiac rhythm.

A

Atrial fibrillation

157
Q

often result from stress, stimulants such as caffeine, or sleep deprivation. They occur either singly or in rapid bursts due to abnormal impulses initiated within the AV node or the ventricular conduction system

A

Premature ventricular contractions (PVCs)

Most PVCs go unnoticed, although occasionally one is perceived as the heart “skipping a beat” and then “jumping” in the chest.

158
Q

a disorganized, rapid, repetitious movement of the ventricular muscle that replaces normal contraction.

A

Ventricular fibrillation

159
Q

This cessation of cardiac activity is called

A

Cardiac Arrest

160
Q

can be used to continue the circulation of blood during cardiac arrest

A

Cardiopulmonary resuscitation (CPR)

161
Q

Attempts to resynchronize cardiac muscle cell electrical activity require use of an

A

automated external defibrillator (AED) or paddle electrodes

162
Q

an atypically slow heartbeat of less than 50

beats per minute.

A

“Bradycardia”

163
Q

a beneficial adaptation resulting from a muscular heart,

healthy circulatory system, and excellent lung capacity.

A

“Athlete’s bradycardia”

164
Q

during embryonic development, blood is shunted from the right atrium to the left atrium by traveling through the ________ and pushing a flap of tissue to the left called the _________

A

foramen ovale, “septum primum”.

165
Q

In embryonic heart development, blood cannot flow back from the left atrium to the right because the _____ acts like a one-way flutter valve.

A

septum primum

166
Q

When a baby is born and the lungs are fully functional, the blood from the left atrium pushes the septum primum closed, creating a closed interatrial septum

A

True

167
Q

The only remnant of the embryonic opening (septum primum) is an oval-shaped depression in the interatrial septum called the ______

A

“fossa ovalis”.

168
Q

Occasionally, the fossa ovalis may fail to close properly (“patent foramen ovale”, “perforated fossa ovalis”, or “atrial septal defect”) allowing blood to flow from the
right atrium to the left atrium, or vice versa.

A

True

169
Q

Such an atrial septal defect (which can occur in up to _________ of the adult population) can lead to poor pulmonary circulation or allow blood clots and undesired materials to travel directly from the venous circulation into the arterial circulation.

A

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Human Anatomy (11 decks)

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