Chapter 6 - Circulatory System Vocabulary Flashcards

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0
Q

After load

A

The pressure in the aorta against which the left ventricle must pump blood

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1
Q

Absolute refractory period

A

The early phases of repolarization in which the cell contains such a large concentration of ions that it cannot be stimulated to depolarize

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2
Q

Agranulocytes

A

Leukocytes that lack granules

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3
Q

Albumins

A

The smallest of plasma proteins; they make up about 60% of these proteins by weight

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4
Q

Alpha effect

A

Stimulation of alpha receptors that result in vasoconstriction

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5
Q

Anemia

A

A lower than normal hemoglobin or erythrocyte level

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6
Q

Anterior descending (LAD) coronary artery

A

One of the two branches of the left main coronary artery

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7
Q

Anti-bodies

A

Proteins secreted by certain immune cells that react against foreign antigens in the body by binding to the antigens, making them more visible to the immune system

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8
Q

Antigens

A

Substances or molecules that, when taken into the body, stimulate immune system response and cause formation of specific protective proteins called anti-bodies

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9
Q

Aorta

A

The principal artery leaving the left side of the heart and caring freshly oxygenated blood to the body; the largest artery in the body

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10
Q

Aortic arch

A

One of the three described portions of the aorta; the secretion of the aorta between ascending and descending portions that gives rise to the right brachiocephalic (innominate), left common carotid, and left subclavian artery

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11
Q

Aortic valve

A

The semi lunar valve that regulates blood flow from the left ventricle to the aorta

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12
Q

Arteries

A

The muscular, thick walled blood vessels that carry blood away from the heart

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13
Q

Arterioles

A

Subdivisions of arteries that are thinner and have muscles in their walls that are innervated by the sympathetic nervous system

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14
Q

Arteriosclerosis

A

A pathologic condition in which the arterial walls become thickened and inelastic

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15
Q

Ascending aorta

A

The first of three portions of the aorta; originates from the left ventricle and gives rise to two branches, the right and left main coronary artery

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16
Q

Atherosclerosis

A

A disorder characterized by the formation of plaques of material, mostly lipids and cholesterol, on the inner arterial walls

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17
Q

Atria

A

The upper chambers of the heart; they receive blood returning to the heart

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18
Q

Atrioventricular (AV) node

A

A specialized structure located in the AV junction that slows conduction through the AV junction

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19
Q

Atrioventricular valves

A

the mitral and tricuspid valve through which blood flows from the atria to the ventricles

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20
Q

Automaticity

A

A state in which the cardiac cells are at rest, waiting for the generation of a spontaneous impulse from within

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21
Q

Axillary vein

A

The vein that is formed from the combination of the basilisc and cephalic vein; it drains into the subclavian vein

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22
Q

B cells

A

Lymphocytes that produce and secrete antibodies that bind and destroy foreign antigens

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23
Q

Baroreceptors

A

Receptors in the blood vessels, kidneys, brain, and heart that respond to changes in pressure in the heart or main arteries to help maintain homeostasis

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24
Q

Basilar artery

A

The artery that is formed when the left and right vertebral arteries unite after entering the brain through the foramen Magnum

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25
Q

Basilic vein

A

One of the two major veins of the arm; it combined with the cephalic vein to form the axillary vein

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26
Q

Basophils

A

White blood cells that work to produce chemical mediators doing an immune response; make up approximately 1% of Leukocytes

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27
Q

beta effect

A

Stimulation of beta receptors that result in increased inotropic, dromotropic, and chronotropic states

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28
Q

Bilirubin

A

A waste product of red blood cell destruction that undergoes further metabolism in the liver

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29
Q

Blood

A

The fluid tissue that is pumped by the heart through the arteries, veins, and capillaries and consist of plasma and formed elements or cells, such as the red blood cells, white blood cells, and platelets

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30
Q

Bruit

A

An abnormal whooshing sound indicating turbulent bloodflow within a narrowed blood vessel; usually heard in the carotid arteries

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31
Q

Bundle of His

A

The portion of the electric conduction system in the interventricular septum that conducts the depolarizing impulse from the atrioventricular junction to the right and left bundle branches

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32
Q

Capillaries

A

Thin walled vessels that allow oxygen and nutrients to pass out into the cells and allow carbon dioxide and waste products to pass from the cells into the capillaries

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33
Q

Cardiac conduction system

A

A group of complex electrical tissues within the heart that initiate and transmit stimuli that results in contractions of myocardial tissue

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34
Q

Cardiac cycle

A

A heartbeat; each cardiac cycle consists of ventricular contraction (systole) and relaxation (diastole)

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35
Q

Cardiac output

A

The amount of blood pumped by the heart per minute, calculated by multiplying the stroke volume by the heart rate per minute

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36
Q

Cardiac tamponade

A

Restriction of cardiac contraction, failing cardiac output, and shock, caused by the accumulation of fluid or blood in the pericardium

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37
Q

Cardiac veins

A

Veins that branch out and drain blood from the myocardial capillaries to join the coronary sinus

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38
Q

Carotid bifurcation

A

The point of division at which the common carotid artery branches at the angle of the mandible into the internal and external carotid arteries

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39
Q

carotid canals

A

An opening in the cranial vault through which the carotid artery enter

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40
Q

carotid sinus

A

A slight dilation in the carotid bifurcation that contains structures that are important in the regulation of blood pressure

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41
Q

Cephalic vein

A

One of the two major veins of the arm that combine to form the axillary vein

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42
Q

Cerebellum

A

The part of the brain that is located dorsal to the pons and is responsible for coordination and balance

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43
Q

Cerebral arteries

A

The arteries that supply blood to large portions of the cerebral cortex of the brain

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44
Q

Chemoreceptors

A

Sense organs that monitor the levels of oxygen and carbon dioxide in the pH of the Cerebrospinal fluid and blood and provide feedback to the respiratory centers to modify the rate and depth of breathing based on the body’s needs at any given time

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45
Q

Chordae tendineae

A

Thin bands of fibrous tissue that attaches to the valves in the heart and prevent them from inverting

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46
Q

Chronotropic effect

A

The effect on the rate of contraction of the heart

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47
Q

Circle of Willis

A

An interconnection of the anterior, middle, and posterior cerebral arteries and the anterior communicating artery, which forms an important source of collateral circulation to the brain

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48
Q

Circulatory system

A

The complex arrangement of tubes, including the arteries, arterials, capillaries, venues, and veins, that moves blood, oxygen, nutrients, carbon dioxide, and cellular waste throughout the body

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49
Q

Circumflex coronary artery and

A

One of the two branches of the left main coronary artery

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50
Q

Coagulation

A

The formation of a blood clot

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51
Q

Conductivity

A

The ability of cardiac cells to conduct electrical impulses

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52
Q

Contractility

A

the strength of heart muscle contraction

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53
Q

Coronary arteries

A

Arteries that arise from the aorta shortly after it leaves the left ventricle and supply the heart with oxygen and nutrients

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54
Q

Coronary artery disease

A

The condition that results when either atherosclerosis or Arteriosclerosis is present in the arterial walls of the heart

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55
Q

Coronary sinus

A

Veins that collect blood that is returning from the walls of the heart

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56
Q

Cusps

A

The flaps that comprise the heart valves

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57
Q

Depolarization

A

The rapid movement of electrolytes across a cell membrane that changes the cells overall charge. This rapid shifting of electrolytes and cellular charges is that main catalyst for muscle contraction and neurotransmitters

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58
Q

Descending aorta

A

One of the three portions of the aorta; it is the longest portion and extends through the thorax and abdomen into the pelvis

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59
Q

Diapedesis

A

A process whereby Leukocytes leave blood vessels to move toward tissue where they are needed most

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60
Q

Dorsalis pedis artery

A

The continuation of the anterior tibial artery at the foot

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61
Q

Dromotropic effect

A

Related to the effect of the hearts conduction rate

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62
Q

Ejection fraction

A

The percentage of blood that leaves the heart each time it contracts

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63
Q

Electrical potential

A

An electrical charge difference that is created by the difference in sodium and potassium concentration across the cell membrane at any given time

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64
Q

Electrocardiogram (ECG)

A

A graphic recording of the electrical activity of the heart

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65
Q

embolus

A

Piece of cloth that travels from one part of the body to another, potentially becoming an obstruction to bloodflow

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66
Q

Endocarditis

A

Inflection of a heart valve

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67
Q

Eosinophils

A

White blood cells with a major role in allergic reactions bronchoconstriction during an asthma attack; makes up approximately 1% to 3% of Leukocytes

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68
Q

Epicardium

A

The layer of the serous pericardium that lies closely against the heart; also called visceral pericardium

69
Q

Epinephrine

A

A hormone produced by the adrenal Medulla that has a vital role in the function of the sympathetic nervous system

70
Q

Erythroblastosis Fetalis

A

A serious condition that results when a pregnant woman’s blood type incompatible with the fetus’ blood type and anti-bodies from the mother answered the fetal circulation and destroy the fetuses red blood cells

71
Q

Erythrocytes

A

Disk shaped cells that carry oxygen to the tissues; also known as red blood cells

72
Q

Excitability

A

A property of cardiac cells that provides the cells with the ability to respond to electrical impulses

73
Q

Erythropoiesis

A

The process by which red blood cells are made

74
Q

Femoral arteries

A

The principal arteries of the thigh, a continuation of the external iliac artery. They supply circulation to the thigh, external genitalia, anterior abdominal wall, and knee

75
Q

Femoral vein

A

A continuation of the saphenous vein the drains into the external iliac vein

76
Q

Fibrin

A

A white insoluble protein formed from fibrinogen in the clotting process

77
Q

Fibrinogen

A

A plasma protein that is important for blood coagulation

78
Q

Foramen ovale

A

An opening between the two atria that is present in the fetus but closes shortly after birth

79
Q

Fossa ovalis

A

A depression between the right and left atria that indicate where the foramen ovale had been located in the fetus

80
Q

Granulocytes

A

A type of leukocytes that has large cytoplasmic granules that are easily seen with a simple light microscope

81
Q

Heart

A

A hollow muscular organ that pumps blood throughout the body

82
Q

Hematocrit

A

The percentage of blood volume made up by red blood cells

83
Q

Hematopoiesis

A

The process of blood so production in the bone marrow; also called hemopoiesis

84
Q

Hemoglobin

A

And iron containing protein within red blood cells that has the ability to bind to oxygen

85
Q

Hemostasis

A

Control of bleeding by formation of a blood clot

86
Q

Heparin

A

A substance found in large amounts and basophils that inhibits blood clotting

87
Q

Hepatic portal system

A

A specialized part of the venous system that drain the blood from the liver, stomach, intestines, and spleen

88
Q

Hepatic vein

A

The veins to which blood empties after liver cells in the sinusoids of the liver extract nutrients, filter the blood, and metabolize the various drugs

89
Q

Histamine

A

A chemical found in mast cells that, when released, causes vasodilation, capillary leaking, and bronchiole constriction

90
Q

Inferior vena cava

A

One of the two largest veins in the body; carries blood from the lower extremities and the pelvic and the abdominal organs to the heart

91
Q

Inotropic effect

A

The effect on the contractility of muscle tissue, especially cardiac muscle

92
Q

Ischemia

A

Insufficient oxygen at a particular tissue site often associated with obstruction of arterial blood flow to the site

93
Q

Jaundice

A

A yellowing of the skin and the sclera of the eyes because of excessive concentration of bilirubin in the blood

94
Q

Jugular vein

A

The two main things that drain the head and neck

95
Q

Leukemia

A

A cancerous condition in which certain white blood cell lines begin to grow abnormally fast and invade other tissues

96
Q

Leukocytes

A

White blood cells that are responsible for fighting infection

97
Q

Lumen

A

The inside of an artery, vein, or other hollow structure

98
Q

Lymphocytes

A

white blood cells responsible for a large part of the body’s immune protection

99
Q

Macrophages

A

Cells that develop from the monocytes that provide some of the body’s first line of defense in the inflammatory process

100
Q

Mast cells

A

Cells to which anti-bodies attached, formed in response to allergens. When allergens attach to antigens on the mast cell surface, the cells release potent inflammatory mediators resulting in an allergic symptoms or potentially anaphylaxis

101
Q

Mediastinum

A

The space between the lungs, in the center of the chest, that contains the heart, trachea, mainstem bronchi, part of the esophagus, and large blood vessels

102
Q

Mesenteric angina

A

Pain caused by partial occlusion of the mesenteric artery from atherosclerosis

103
Q

Mitral valve

A

The valve in the heart that separates the left atrium from the left ventricle

104
Q

Monocytes

A

Granulocytes that migrate out of the blood and into tissues in response to an infection

105
Q

Murmur

A

An abnormal heart sound, heard as whooshing, indicating turbulent bloodflow within the heart

106
Q

Myocardial infarction

A

Blockage of one or more of the arteries that supply oxygen to the heart, resulting in death to a portion of the myocardium

107
Q

Myocardium

A

The heart muscle

108
Q

Neutrophils

A

White blood cells that are one of the three types of granulocytes; they have multi-lobed nuclei that resemble a string of baseballs held together by a thin strands of thread; they destroy bacteria, antigen-antibody complexes, and foreign matter

109
Q

Norepinephrine

A

A naturally occurring hormone with a greater stimulator effect on alpha receptors that also may be given as a cardiac drugs

110
Q

P wave

A

The first wave in the ECG complex, representing depolarization of the atrium

111
Q

Palmer arches

A

The two arches formed from the radial and ulnar vessels within the head, creating the superficial and deep palmar arches

112
Q

Papillary muscles

A

Specialized muscles attach the ventricle to the cusps of the valves by muscular strands called chordae tendineae

113
Q

Parietal layer

A

One of two layers of the serous pericardium; it is a separate from the visceral pericardium by a small amount of pericardial fluid

114
Q

Pericardial effusion

A

A condition, often caused by trauma in which the pericardial sac fills with too much fluid, and impairing the heart’s ability to expand and contract properly

115
Q

Pericardial fluid

A

A serous fluid that fills the space between the visceral pericardium and the parietal pericardium and helps to reduce friction

116
Q

Pericardial sac

A

A thick, fibrous membrane that surrounds the heart; also called the pericardium

117
Q

Pericardiocentesis

A

A life-saving procedure to correct cardiac Tampanade, in which a needle is inserted into the pericardial sac to remove excess fluid that is restricting the heart from expanding and contracting properly

118
Q

Pericarditis

A

Infection or inflammation of the pericardial membranes, resulting in severe chest pain

119
Q

Pericardium

A

A thick, fibrous membrane that surrounds the heart; also called the pericardial sac

120
Q

Phlebitis

A

Inflammation of the wall of the vein, sometimes caused by an IV line, manifested by tenderness, redness, and slight edema along part of the length of the vein

121
Q

Plasma

A

A sticky yellow fluid that carried blood cells and nutrients and transports cellular waste material to the organs of excretion; makes up 55% of the total blood volume

122
Q

Plasma proteins

A

The most abundant solutes (dissolved substances) in the plasma

123
Q

Plasmin

A

A naturally occurring clot-dissolving enzyme, usually present in the body in its inactive form, plasminogen

124
Q

Platelets

A

Tiny, disk-shaped cell fragments that are much smaller than the red or white blood cells; they are essential in the initial formation of a blood clot, the mechanism that stops bleeding

125
Q

Polarized state

A

The state of the resting cell, which normally has a net negative charge with respect to the outside of the cell

126
Q

Pons

A

The mass of nerve fibers at the end of the Medela oblongata

127
Q

Popliteal artery

A

A continuation of the femoral artery at the knee

128
Q

Popliteal vein

A

The vein that forms when the anterior and posterior tibial vein unite at the knee

129
Q

PR segment

A

The period between the beginning of the P wave (atrial depolarization) and the onset of the QRS complex (ventricular depolarization), signifying the time required for atrial depolarization and passage of the excitation impulse through the atrioventricular junction

130
Q

Prothrombin

A

An alpha globulin made in the liver that is converted to thrombin

131
Q

Pulmonary circuit

A

The venules and veins, which send deoxygenated blood to the lungs to receive oxygen and unload carbon dioxide

132
Q

Pulmonary embolism

A

A blood clot or foreign matter trapped within the pulmonary circulation

133
Q

Pulmonary valve

A

The semi lunar valve that regulates blood flow between the right ventricle and the pulmonary artery

134
Q

QRS complex

A

Deflections of the ECG produced by ventricular depolarization

135
Q

Raynaud phenomenon

A

Spasms the developed in the digital arteries, particularly following emotional stress or cold exposure, resulting in white and cool fingertips

136
Q

Red blood cells

A

Cells that transfer gases, including oxygen; also called erythrocytes

137
Q

Relative refractory period

A

The latter phase of repolarization in which the cells are able to respond to a stronger than normal stimulus

138
Q

Repolarization

A

The process by which ions are moved across the cell wall to return to a polarized state.

139
Q

Rheumatic fever

A

An inflammatory disease caused by streptococcal bacterial infection that can cause a stenosis of the mitral valve or aortic valve

140
Q

Saphenous vein

A

The longest vein in the body, it drains the leg, thigh, and dorsum of the foot

141
Q

Semi lunar valves

A

The two valves, the aortic and pulmonic valves, that divide the heart from the aorta and pulmonary artery

142
Q

Septum

A

A solid, wall-like structure that separates the left atrium and ventricle from the right atrium and ventricle

143
Q

Serous pericardium

A

The inner membrane of the pericardium, which contains two layers called the visceral pericardium and the parietal pericardium

144
Q

Sinoatrial (SA) node

A

The dominant pacemaker of the heart, located at the junction of the superior Vena cava and the right atrium

145
Q

Sinusoids

A

A part of the hepatic portal system in which blood collects within the liver and the liver cells extract nutrients from the blood, filter the blood, and metabolize various drugs.

146
Q

Sodium-potassium pump

A

A molecular (ion-transporting) mechanism whereby sodium is actively moves out of a cell and potassium moved in

147
Q

ST Segment

A

The interval between the end of the QRS complex and the beginning of the T wave; often elevated or depressed with respect to the isoelectric line when there is significant myocardial ischemia.

148
Q

Stroke volume

A

The volume of blood pumped forward with each ventricular contraction

149
Q

Subclavian artery

A

The proximal part of the main artery of the arm, which supplied the brain, neck, anterior chest wall, and shoulder.

150
Q

Subclavian vein

A

The proximal part of the main vein of the arm, which unites with the internal jugular vein and terminates at the superior vena cava.

151
Q

Superior vena cava

A

One of the two largest veins in the body; carries blood from the upper extremities, head, neck, and chest into the heart

152
Q

Systemic circuit

A

The arteries and arterioles, which send oxygenated blood and nutrients to the body cells while removing wastes

153
Q

Systole

A

The period of time when the atria or ventricles are contracting; also called atrial or ventricular systole.

154
Q

T cells

A

Lymphocytes that interact directly with antigens, producing the cellular immune response; they also stimulate the B lymphocytes to produce antibodies.

155
Q

T wave

A

The upright, flat, or inverted wave following the QRS complex of the ECG, representing ventricular repolarization.

156
Q

Thrombi

A

Blood clots

157
Q

Thrombin

A

An enzyme that causes the conversion of fibrinogen to fibrin, which binds to the platelet plug, forming the final mature clot.

158
Q

Thrombocytes

A

Incomplete cells important in blood clotting; also called platelets

159
Q

Tibial veins

A

A continuation of the veins of the feet that unite at the knee to form the popliteal vein, which then drains into the femoral vein.

160
Q

Tissue plasminogen activator

A

An important element of the fibrinolytic system; causes clots that have already formed to lyse or be disrupted; works by converting plasminogen to plasmin

161
Q

Tricuspid valve

A

The heart valve that separates the right atrium from the right ventricle

162
Q

Tunica media

A

The middle and thickest layer of tissue of a blood vessel wall, composed of elastic tissue and smooth muscle cells that allow the vessel to expand or contract in response to changes in blood pressure and tissue demand.

163
Q

Vasoconstriction

A

The contraction of blood vessels, which decreases their diameter

164
Q

Vasodilation

A

The relaxation of blood vessels, which increases their diameter

165
Q

Vasospasm

A

The action of a muscle contraction in a small blood vessel that occurs after it is cut or broken; this action can completely close the end of a severed vessel.

166
Q

Veins

A

The blood vessel that brings blood back to the heart.

167
Q

Venous sinuses

A

Spaces between the membranes surrounding the brain that are the primary means of venous drainage from the brain.

168
Q

Ventricles

A

The two lower chambers of the heart that pump blood out of the heart.

169
Q

Venules

A

Microscopic vessels that link capillaries to veins.

170
Q

Visceral layer

A

The layer of the serous pericardium that lies closely against the heart; also called the epicardium

171
Q

White blood cells

A

Cells that protect the body against disease, particularly infectious disease; also called Leukocytes