Blood, Heart, & Blood Vessels Flashcards
Test/quiz preparation (293 cards)
1
Q
____ circulation functions only for the exchange of gases
A
Pulmonary
2
Q
Exchange occurs at capillary beds because of:
A
Hydrostatic pressure and osmotic pressure
3
Q
_____ account for most of the named arteries studied in the anatomy laboratory
A
Muscular arteries
4
Q
____ is the build up of plaque in arteries that can develop into blockage.
A
Atherosclerosis
5
Q
____ are formed from merging venules.
A
Veins
6
Q
____ are blood vessels that have valves
A
Veins
7
Q
3 types of arteries are:
A
Elastic, muscular, and arterioles
8
Q
The cardiovascular center of the brain consists of the ____
A
Cardiac centers and the vasomotor center
9
Q
____ is the joining together of blood vessels to allow for alternative routes for blood to reach the same organ.
A
Vascular anastomosis
10
Q
Arteries have a smaller ____ and thicker ____ than corresponding veins
A
Lumen, tunica
11
Q
____ is low blood pressure
A
Hypotension
12
Q
Resistance is regulated by physical factors including:
A
Blood vessel diameter, blood viscosity, blood vessel length
13
Q
Vasoconstriction is directly triggered by the hormone ____
A
Angiotensin II
14
Q
Explain what happens to the heart of a patient with hypertrophic cardiomyopathy.
A
The heart muscle becomes thickened and causes interference with the heart’s electrical systems
15
Q
Veins tend to collapse because:
A
They have thinner tunica and larger lumen than corresponding veins
16
Q
Oxygen-poor blood is drained from the liver via the ____
A
Hepatic veins
17
Q
When measuring BP, the pressure read when the first tapping sounds are heard is the ____ pressure.
A
Systolic
18
Q
The middle tunic is the ____.
A
Tunica Media
19
Q
Indirect renal mechanisms involve the use of ____ to regulate BV.
A
Hormones
20
Q
Anastomosis occurs more frequently in ____.
A
Veins
21
Q
True or False: There are brachiocephalic veins in the left and right superior regions of the body.
A
True
22
Q
Larger ____ have all three tunics, but their tunica media is chiefly smooth muscle with a few scattered elastic fibers.
A
Arterioles
23
Q
The middle layer in blood vessels, composed of smooth muscle and elastic fibers.
A
Tunica Media
24
Q
____ does not directly serve the metabolic needs of the body.
A
Pulmonary circulation
25
\_\_\_\_ capillaries are similar to the continuous variety except that the endothelial cells are riddled with oval pores, called \_\_\_\_.
Fenestrated, fenestrations
26
The outermost layer of a blood vessel is called the \_\_\_\_.
Tunica externa
27
Oxygen-poor blood is drained from the kidneys via the \_\_\_\_.
Renal veins
28
T/F: There are brachiocephalic trunks in the left and right superior regions of the body.
False
29
These arteries are the largest in diameter:
Elastic arteries
30
\_\_\_\_ triggers the retention of water.
Antidiuretic hormone (ADH)
31
In ____ there is an elastic membrane on each face of the tunica media.
Muscular arteries
32
\_\_\_\_ are continuous in the sense that their endothelial cells are joined together by tight junctions, providing an uninterrupted lining.
Continuous capillaries.
33
Most neural controls there determine regulate blood pressure operate via reflex arcs involving \_\_\_\_.
Baroreceptors
34
Baroreceptors sympathetically stimulate the release of renin by the \_\_\_\_.
Kidneys
35
Defined as the tendency of fluid to move from an area of higher concentration to an area of lower concentration:
osmotic gradient/osmotic pressure
36
A person whose heart muscle becomes thickened shows signs of \_\_\_\_.
Hypertrophic cardiomyopathy
37
\_\_\_\_ are the thick-walled arteries near the heart.
Elastic arteries
38
\_\_\_\_ supply blood to the myocardium; branches off of the \_\_\_\_.
Right & left coronary arteries; ascending Aorta
39
Hypertension is characterized by a sustained increase in blood pressure over \_\_\_\_
140/90
40
Smaller ____ are little more than a single layer of smooth muscle cells spiraling around the endothelial lining.
Arterioles
41
\_\_\_\_ form when the valves in veins weaken of collapse due to muscular constriction, such as obesity or pregnancy.
Varicose veins
42
Interweaving, interdependent network of capillaries:
Capillary beds
43
The ANS reduces blood pressure by altering \_\_\_\_
cardiac output and peripheral resistance
44
Oxygen-rich blood is supplied to the liver via the \_\_\_\_
Hepatic artery proper
45
\_\_\_\_ form anastomoses more frequently
Veins
46
T/F: The celiac truck branches from the abdominal aorta to provide blood supply to the digestive organs in the abdominal cavity
True
47
The ____ alters blood volume independently of hormones.
Direct renal mechanism
48
Arteries run deep while veins \_\_\_\_.
run both deep and superficially
49
When aortic pressure drops to its lowest level during vascular relaxation, it is called the ____ pressure.
Diastolic
50
\_\_\_\_ connects arterioles & venules; act as the exchange sites for blood
Capillaries
51
Oxygen-rich blood is supplied to the legs via the \_\_\_\_
Femoral arteries
52
Short-term regulation of blood pressure is maintained by ____ and \_\_\_\_.
the nervous system and blood borne hormones
53
Renin acts as an enzyme, ultimately generating \_\_\_\_, which stimulates intense vasoconstriction, promoting a rapid rise in systemic blood pressure.
Angiotensin II
54
The walls of the smaller venues consists of \_\_\_\_
entirely endothelium
55
Oxygen-poor blood is routed to the hepatic portal vein from the \_\_\_\_, \_\_\_\_, and \_\_\_\_.
Superior mesenteric vein, inferior mesenteric vein, and splenic vein
56
A person who's ventricles have become dilated and cannot produce enough force to pump out blood exhibits signs of \_\_\_\_.
Dilated cardiomyopathy
57
\_\_\_\_ is the enzyme released by the kidneys that results in the formation of Angiotensin II
Renin
58
Blood flow is directly proportional to ____ and inversely proportional to \_\_\_\_.
Blood pressure, resistance
59
\_\_\_\_ arteries have a thick tunica media with a large smooth muscle content and little elastin
Muscular
60
\_\_\_\_ is the opposition of blood flow
Resistance
61
Veins have ____ that depend on skeletal muscle contraction, breathing movements, and vasoconstriction to move blood toward the heart.
valves
62
Proportionately, muscular arteries have the thickest ____ of all vessels.
Tunica media
63
When taking blood pressure, the pressure at which the sounds disappear is the ____ pressure.
Diastolic
64
Dilated cardiomyopathy results in ____ .
The ventricles becoming dilated and unable to produce enough fore to pump blood out
65
Blood vessels form special connections called
vascular Anastomosis
66
The ____ relies on skeletal muscle activity to pump blood throughout the veins.
Muscular pump
67
The respiratory pump moves blood upward throughout the veins by \_\_\_\_
Breathing movements changing the pressure in the ventral body cavity
68
Disease of the heart in which the myocardium becomes enlarged and weakened
Cardiomyopathy
69
\_\_\_\_ are highly modified, leaky capillaries found only in the liver, bone marrow, spleen, and adrenal medulla.
Sinusoids, or sinusoidal capillaries
70
In some cases, one endothelial cell forms the entire circumference of the ____ wall.
Capillary
71
The ____ contains the endothelium
Tunica intima
72
The activity of the smooth muscle cells in arteries is regulated by ____ and \_\_\_\_.
Vasomotor nerve fibers of the ANS and a large number of chemicals
73
Generally, the tunica media is the bulkiest layer in \_\_\_\_
Muscular arteries
74
The walls of veins are always ____ and their lumens ____ than those of corresponding arteries.
thinner, larger
75
\_\_\_\_ mechanisms mediate long-term regulation of BP.
Renal
76
Elastic arteries are ____ pathways that conduct blood from the heart to the medium-sized arteries.
Low-resistance
77
Why do the names of the superficial veins not correspond to the names of any of the arteries?
Because there are no superficial arteries
78
Pressure results when flow is opposed by \_\_\_\_.
Resistance
79
Defined as the force exerted by fluid as it expands against the walls of the vessel it is contained in.
Hydrostatic pressure
80
The atria of the heart produce the hormone \_\_\_\_, which leads to a reduction in blood volume and blood pressure.
ANP
81
In the ____ system, the pressure inside the vessels lessens as the vessels get nearer to the heart.
Veinous.
82
The measure of the amount of friction blood encounters as it passes throughout the vessels is \_\_\_\_
resistance
83
\_\_\_\_ are pressure reservoirs, expanding and recoiling as the heart ejects blood.
Elastic arteries
84
\_\_\_\_ are just large enough to allow limited passage of fluids and small solutes.
Intercellular clefts
85
The endothelial lining of ____ has fewer tight junctions and larger intercellular clefts than ordinary capillaries.
Fenestrated capillaries
86
\_\_\_\_ are the arteries found closes to the heart.
Elastic arteries
87
The outermost layer of a blood vessel is the \_\_\_\_
Tunica externa
88
This pressure peak generated by ventricular contraction is called the ____ pressure.
Systolic
89
Blood pressure varies directly with ____ .
Blood volume
90
Systemic blood pressure is highest in the \_\_\_\_
Aorta
91
Chronically elevated blood pressure is called \_\_\_\_
Hypertension
92
\_\_\_\_ are found wherever active capillary absorption or filtrate formation occurs.
Fenestrated capillaries
93
\_\_\_\_ contain more elastin than any other vessel type.
Elastic arteries.
94
\_\_\_\_ are leaky & highly permeable
Capillaries
95
\_\_\_\_ is the force per unit area exerted on a blood vessel wall.
Blood pressure (BP)
96
\_\_\_\_ pinch off to limit blood flow.
Arterioles
97
Innermost layer of a blood vessel:
Tunica intima
98
\_\_\_\_ are formed when capillaries marge.
Venules
99
Two types of cardiomyopathy are ____ and \_\_\_\_
dilated and hypertrophic
100
\_\_\_\_ is a process that reduces the volume of blood in veins during stress.
Sympathetic Vasoconstriction
101
Hypotension is blood pressure below \_\_\_\_
100 mm Hg
102
\_\_\_\_ triggers the release of ADH and Aldosterone to help regulated BV.
Angiotensin II
103
Sinusoids have ____ lumens, and are usually fenestrated.
large, irregularly shaped
104
Larger ____ have one or two layers of smooth muscle cells, and a thin tunica externa.
Venules
105
Blood pressure is regulated by physical factors including \_\_\_\_
cardiac output and peripheral resistance
106
The innermost tunic is the \_\_\_\_
Tunica Intima
107
The pumping action of the heart generates \_\_\_\_
Blood flow
108
The ____ carries the nutrient-rich blood from the digestive organs to the liver, where it can be cleaned of toxins before it reaches the rest of the body.
Hepatic portal artery
109
Aldosterone is secreted by the adrenal cortex to promote the retention of \_\_\_\_
Sodium
110
\_\_\_\_ deliver blood to specific body organs (sometimes called distributing arteries)
Muscular arteries
111
In the ____ renal mechanism, the kidneys do the actual work for regulation of ____ .
Direct, blood volume
112
The ____ provides the functional blood supply to all body tissues.
Systemic circulation
113
Long-term BP regulation is achieved by the kidneys altering ____ over time.
Blood volume
114
During periods of stress, the adrenal gland releases ____ and \_\_\_\_
Epinephrine and norepinephrine
115
The difference between systolic and diastolic pressures is called the \_\_\_\_
Pulse pressure
116
\_\_\_\_ and ____ carry blood back to the heart from the body.
Veins and venules
117
\_\_\_\_ stimulates the kidneys to conserve water.
antidiuretic hormone (ADH)
118
\_\_\_\_ are the smallest blood vessels
Capillaries
119
\_\_\_\_ form a continuous circuit of tubes that carries blood from the heart to the body and back.
Blood vessels
120
\_\_\_\_ and\_\_\_\_ carry blood away from the heart.
Arteries and arterioles
121
The skeletal pump works by \_\_\_\_
Skeletal muscles surrounding the deep veins relaxing and contracting in order to "milk" the blood upward towards the heart
122
\_\_\_\_ is the volume of blood flowing through a vessel, an organ, or the entire circulation in a given period.
Blood flow
123
Parasite killing granulocytes.control inflammation & allergic reactions
Eosinophils
124
About 85% of americans are Rh+, meaning their RBCs carry \_\_\_\_
the D antigen
125
The shape of ____ allows for maximal surface area.
Erythrocytes/RBCs
126
An ____ is anything the body perceives as foreign and that generates an immune response
Antigen
127
Phagocytic granulocytes:
Neutrophils
128
Proerythroblasts give rise to \_\_\_\_
Basophilic erythroblasts
129
Hemoglobin is made up of the red ____ bound to the \_\_\_\_
Heme pigment, protein Globin
130
Once a basophilic erythroblast synthesizes enough hemoglobin and accumulates enough iron, it transforms into a ____ and then a \_\_\_\_
Polychromatic erythroblast, orthochromatic erythroblast
131
Blood accounts for approximately \_\_\_\_% of body weight.
8%
132
\_\_\_\_ account for 2-4% of all WBCs and are approximately the size of Neutrophils.
Eosinophils
133
\_\_\_\_ regulates the formation of platelets
Thrombopoietin
134
\_\_\_\_ is characterized by an abnormally low white blood cell count.
Leukopenia
135
Erythropoiesis begins when a hematopoietic stem cell descendent called a ____ transforms into a proerythroblast.
Myeloid stem cell.
136
Leukocytes and platelets contribute \_\_\_\_% of blood volume
137
Most of the formed elements are not true cells because \_\_\_\_
They do not contain a nucleus
138
In blood, iron is transported loosely-bound to a transport protein called \_\_\_\_
Transferrin
139
The formed elements of blood and their percentages
Erythrocytes: 45% Plasma: 55% Leukocytes:
140
The rarest white blood cells accounting for only 0.5-1% of the leukocyte population.
Basophils
141
Their cytoplasm contains large, coarse, histamine-containing granules.
Basophils
142
When oxygen detaches tom iron in a hemoglobin, the hemoglobin resumes its former shape and the result is a \_\_\_\_
deoxyhemoglobin
143
The most common blood type in North America (nearly 85%) is \_\_\_\_
Type O+
144
In healthy males, hematocrit values vary between ____ , in females \_\_\_\_
47% ± 5%, 42% ± 5%
145
\_\_\_\_ is an abnormal excess or erythrocytes
Polycythemia
146
\_\_\_\_ are essential for the clotting process
Platelets
147
Anticoagulant granulocytes:
Basophils
148
\_\_\_\_ are chemically attracted to sites of inflammation and are active phagocytes.
Neutrophils
149
When mismatched blood is transfused, a transfusion reaction occurs in which the recipients plasma agglutinins \_\_\_\_
attack the donor red blood cells.
150
Preformed antibodies present in the plasma are called \_\_\_\_
agglutinins
151
The four formed elements of blood are \_\_\_\_
Plasma, erythrocytes, leukocytes, platelets
152
Antibody-producing Agranulocytes
Lymphocytes
153
The general functions of blood include \_\_\_\_
protection, transport, regulation, and distribution
154
Since these RBC antigens promote agglutination, they are more specifically called \_\_\_\_
agglutinogens
155
Our body's bacteria slayers are \_\_\_\_
Neutrophils
156
Blood is a fluid \_\_\_\_
connective tissue
157
When their lifespan is complete, RBCs are broken down. The ____ is stripped down and the amino acids recycled, and the ____ is released back into the blood stream.
Globin, heme
158
Plasma makes up \_\_\_\_% of whole blood
55%
159
The presence of neither A nor B agglutinogens results in which blood type?
Type O
160
The presence of agglutinogen A results in which blood type?
Type A
161
Damaged blood vessels respond to injury by \_\_\_\_
Constricting
162
Bilirubin is secreted as bile into the small intestine, and then \_\_\_\_
excreted in the feces
163
\_\_\_\_ are leukocytes that produce antibodies.
Lymphocytes
164
Platelet deficiency
Thrombocytopenia
165
The most numerous WBCs, which account for \_\_\_\_% of WBC population are the \_\_\_\_
50-70%, Neutrophils
166
When an orthochromatic erythroblast has accumulated almost all of its hemoglobin, it \_\_\_\_
Extrudes it organelles and pinches off its nucleus
167
The nucleus of this leukocytes is distinctively U- or kidney-shaped.
Monocytes
168
After ____ days, the liver breaks down the old, dead RBCs.
100-120
169
Lymphocytes account for \_\_\_\_% of the WBC population.
25% or more
170
Overproduction of abnormal leukocytes occurs in ____ and infections mononucleosis.
leukemia
171
Too many erythrocytes or excessive oxygen in the blood stream depresses \_\_\_\_
EPO production
172
\_\_\_\_ and ____ are protein-iron complexes that store toxic free iron ions.
Ferriten and hemosiderin
173
Cytoplasmic fragments of extraordinarily large cells called megakaryocytic:
platelets
174
During hemostasis, \_\_\_\_, \_\_\_\_, and ____ occur is rapid succession.
Vascular spasm, platelet plug formation, coagulation
175
Vitamin E quinone is a potent \_\_\_\_
anticoagulant
176
Coagulation reinforces the platelet plug formation with ____ that act as a "molecular glue" for the aggregated cells.
Fibrin threads
177
\_\_\_\_ have large, dark-purple nucleus that occupies most of the cells volume, the nucleus is usually spherical but may be slightly dented.
lymphocytes
178
The presence of agglutinogens A & B result in which blood type?
Type AB
179
Erythrocytes normally constitute about \_\_\_\_% of the total volume of blood. This is a percentage known as the ____ value.
45%, hematocrit
180
Depending on which group of agglutinogens a person inherits, their blood type will be either \_\_\_\_
A, B, AB, or O
181
When do reticulocytes usually become fully mature erythrocytes?
Within 2 days of being released into the blood stream
182
The composition of ____ varies continuously as cells remove or add substances to the blood.
Plasma
183
Erythrocytes are completely dedicated to their job of \_\_\_\_
Transporting respiratory gases
184
The lease prevalent blood type with both antigens is \_\_\_\_
Type AB
185
\_\_\_\_ are leukocytes that have complex roles in many other diseases including allergies and asthma
Eosinophils
186
Uncontrolled body-wide clotting in undamaged vessels that may lead to hemorrhaging is called \_\_\_\_
disseminated intravascular coagulation (DIC)
187
\_\_\_\_ give rise to reticulocytes.
Orthochromatic erythroblasts
188
Most oxygen carried in blood is bound to \_\_\_\_
hemoglobin
189
What is the function of erythrocytes?
Transporting O2 and CO2 throughout the blood stream
190
Undesirable, over-abundant clot formation (embolisms)
Thromboemolytic disorder
191
\_\_\_\_ is a condition in which the blood's oxygen-carrying capacity is too low to support normal metabolism.
Anemia
192
What is the function of platelets?
forming clots to seal small tears in blood vessels walls
193
The presence of agglutinogen B results in ____ blood.
Type B
194
Monocytes account for \_\_\_\_% of WBCs
3-8%
195
The formed elements of blood originate from \_\_\_\_
red bone marrow
196
Blood plasma is \_\_\_\_
a sticky, straw-colored fluid made up of mostly water along with a mixture of both organic and inorganic substances dissolved within it, including proteins and plasma proteins
197
The ABO blood groups are based on the presence or absence of \_\_\_\_
agglutinogens A and B
198
The O blood group has which agglutinogens?
Neither
199
The ____ play the major role in EPO production.
Kidneys
200
The natural anticoagulant contained in basophil and mast cell granules as well as on the surface of endothelial cells is \_\_\_\_
Heparin
201
Neutrophils are what size compared to a RBC?
about twice as large
202
Clotting factor deficiency is called \_\_\_\_
Hemophilia
203
The protein that makes red blood cells red and binds easily and reversibly with oxygen is called \_\_\_\_
Hemoglobin
204
Albumin accounts for nearly 60% of \_\_\_\_
plasma proteins
205
The most important role of ____ is to lead the counterattack against parasitic worms.
Eosinophils
206
The glycoprotein hormone that stimulates the formation of erythrocytes is called \_\_\_\_
Erythropoietin (EPO)
207
When oxygen binds to iron in a hemoglobin, the hemoglobin is now called \_\_\_\_
oxyhemoglobin
208
Erythropoiesis is the \_\_\_\_
formation of erythrocytes
209
A phagocytic agranulocyte is the \_\_\_\_
Monocyte
210
Leukemia is ____ if it derives from stem cells, and ____ if it involves proliferation of later cell stages.
Acute, chronic
211
What is the function of leukocytes?
Protecting the body from invaders and warding off infection
212
Platelets play a key role in hemostasis by \_\_\_\_, forming a plug that temporarily seals the break in the vessel wall.
Aggregating.
213
The glycoprotein markers on the plans membrane of erythrocytes are called \_\_\_\_
antigens
214
The ____ on an EKG is the period from the beginning of ventricular depolarization through ventricular depolarization.
Q-T interval
215
The ____ returns blood from body areas below the diaphragm.
Inferior vena cava
216
\_\_\_\_ are the discharging chambers of the heart
Ventricles
217
The ____ is continuous with the endothelial linings of the blood vessels leaving and entering the heart.
Endocardium
218
En electrocardiogram (ECG) is a \_\_\_\_
graphic record of the electrical activity of the heart
219
The ____ complex results from ventricular depolarization and precedes ventricular contraction.
QRS complex
220
The ____ circulation is the functional blood supply of the heart
Coronary
221
From the SA node, the depolarization wave spreads via gap junctions throughout the atria to the \_\_\_\_
AV node
222
The ____ wave results from movement of the depolarization wave from the SA node through the atria
P-wave
223
The superficial part of the pericardium is the \_\_\_\_
fibrous pericardium
224
The ____ are the receiving chambers for blood returning to the heart.
Atria
225
\_\_\_\_ is an abnormally fast heart rate (more than 100 BPMs)
Tachycardia
226
The muscle bundles in the anterior portion of the right atria are called \_\_\_\_
pectinate muscles
227
\_\_\_\_ complete the pathway of the heart's electrical system through the inter ventricular septum.
Purkinje Fibers
228
Due to gap junctions, the myocardium behaves as a single, coordinated unit, or \_\_\_\_
functional syncitium
229
Between the parietal and visceral layers is the \_\_\_\_, which contains a film of serous fluid.
Pericardial cavity
230
\_\_\_\_ , or abnormally low heart rate, may result from low body temperature, certain drugs, or parasympathetic nervous activation.
Bradycardia
231
Deep to the fibrous pericardium is the \_\_\_\_
serous pericardium
232
When the cardiac muscle cells reach threshold, ____ channels open
Ca2+ (calcium)
233
The chordae tendinae and the ____ serve as guy-wires that anchor the valve flaps.
Papillary muscles
234
The ____ layer lines the internal surface of the fibrous pericardium.
Parietal
235
The ability of cardiac muscle to depolarize and contract is \_\_\_\_
intrinsic
236
When the ____ contract, they propel blood out of the heart into the circulation
Ventricles
237
The bulk of the heart muscle is composed of ____ responsible for the heart's pumping activity.
contractile muscle fibers.
238
The heart sound that occurs at the beginning of ventricular relaxation is the sound of the
SL valves closing
239
The heart continues to beat rhythmically even if all nerves connected to it are severed. This is due to \_\_\_\_
autorhythmic cells
240
The posterior and anterior regions of the right atrium are separated by a c-shaped ridge called the \_\_\_\_
Crista terminalis
241
The ____ collects blood draining from the myocardium
Coronary sinus
242
The left ventricle ejects blood into the \_\_\_\_
Aorta
243
3 functions of the fibrous pericardium are \_\_\_\_
Anchoring the hear to surrounding structures, protecting the heart, and preventing overfilling of the heart with blood.
244
Cardiac muscle cells that are self-excitable are called \_\_\_\_
Autorhythmic cells
245
During the ____ segment of the ECG, the entire ventricular myocardium is depolarized.
S-T segment
246
From the AV node, the impulse sweeps to the \_\_\_\_
AV bundle
247
\_\_\_\_, or abnormally high heart rate, may result from elevated body temperature, stress, certain drugs, or heart disease.
Tachycardia
248
Tiny white collagen cords which anchor the valve cusps to the papillary muscles are called \_\_\_\_
chordae tendinae
249
The interatrial septum bears a shallow depression called the ____ that marks the spot where an opening once existed in the fetal heart.
fossa ovalis
250
These cells can initiate not only their own depolarization, but that of the rest of the heart as well.
autorhythmic cells
251
In cardiac cells, the ____ period lasts over 200 milliseconds.
absolute refractory
252
The brain center which causes a parasympathetic reduction in heart rate is called the \_\_\_\_
Cardioinhibitory center
253
\_\_\_\_ increases when stroke volume increase of the dart beats faster.
Cardiac output
254
\_\_\_\_ is a heart rate slower than 60 beats/min.
Bradycardia
255
Pulmonary veins enter the \_\_\_\_
left atrium
256
Inner layer of the pericardium which is an integral part of the heart wall is called the \_\_\_\_
visceral layer or pericardium
257
The term ____ referred to periods of cardiac contraction
Systole
258
Irregular ridges of muscle called ____ mark the internal walls of the ventricular chambers.
Trabeculae carnae
259
The internal partition that divides the heart longitudinally is called the ____ where it separates the atria, and the ____ where it separates the ventricles.
interatrial septum, interventricular septum
260
The ____ includes all events associated with the blood flow through the heart during one complete heartbeat.
cardiac cycle
261
The right ventricle pumps blood into the \_\_\_\_
pulmonary trunk
262
The ____ sets the pace for the heart.
SA node
263
The cells of the heart that make up the intrinsic conduction system of the heart are called \_\_\_\_
pacemaker cells or autorhythmic cells
264
The result of the influx of Na+ and the loss of K+ is that that membrane interior \_\_\_\_, also known as ____ .
becomes less and less negative, hyperpolarization
265
The first heart sound occurs as the ____ valves close/open.
AV valves close
266
The ____ is composed mainly of the cardiac muscle and forms the bulk of the heart.
Myocardium
267
The action potentials that spread throughout the heart to trigger its rhythmic contractions are called \_\_\_\_
pacemaker potentials
268
\_\_\_\_ is essentially fatty buildup that clogs the coronary arteries.
Atherosclerosis
269
Connective tissue fibers in the myocardium form a dense network called the \_\_\_\_
fibrous cardiac skeleton
270
The ____ returns blood from body regions superior to the diaphragm.
Superior vena cava
271
The ____ is due to the special properties of the ion channels in the sarcolemma
pacemaker potential
272
The ____ is the visceral layer of the serous pericardium.
superficial epicardium
273
The ____ is the time from the beginning go atrial excitation to the beginning of ventricular excitation.
P-R interval
274
Located on the inner myocardial surface, the ____ lines the inside of the heart chambers and covers the fibrous skeleton of the valves.
Endocardium
275
The auto rhythmic impulse of the heart is delayed at the \_\_\_\_
AV node
276
The long cardiac refractory period normally prevents \_\_\_\_
tetanic contractions
277
The hear is enclosed within the body cavity called the \_\_\_\_
mediastinum
278
\_\_\_\_ make up most of the volume of the heart.
Ventricles
279
Cardiac pacemaker cells make up about \_\_\_\_% of cardiac muscle fibers.
1%
280
The right AV valve is called the \_\_\_\_
Tricuspid valve
281
The heart lies ____ to the vertebral column, and ____ to the sternum.
Anterior, posterior
282
Hyperpolarization at the end of an action potential both closes ____ channels and opens ____ channels.
K+ and slow Na+ channels
283
The ____ wave on an EKG is caused by ventricular depolarization.
T-wave
284
The ____ consists of non contractile cardiac cells specialized to initiate and distribute impulses throughout the heart.
intrinsic cardiac conduction system
285
The AV bundle splits into the right and left \_\_\_\_
bundle branches
286
\_\_\_\_ in cardiac muscle cells tie all of the individual cells together electorally to coordinate them as one unit.
Gap junctions
287
The heart is enclosed in a double-walled sac called the \_\_\_\_
pericardium
288
The brain center which triggers the heart to speed up in times of stress is the \_\_\_\_
cardioacceleratory center
289
\_\_\_\_ is the amount of blood pumped out by each ventricle in 1 minute.
cardiac output
290
Once cardiac depolarization is complete, ____ channels close.
K
291
The left AV valve with two cusps is called the \_\_\_\_
Bicuspid or mitral
292
The heart sound the occurs at the beginning of ventricular relaxation is the sound of the \_\_\_\_
SL valves closing
293
\_\_\_\_ refers to the period of relaxation in either the ventricles or the atria.
Diastole.
