11 Cardiovascular System Flashcards
1
Q
Cardiovascular system made of
A
Heart and blood vessels
Closed system
2
Q
Function of cardiovascular system
A
Transport O2
Nutrients
Cell wastes
Hormones to and from
3
Q
Size and weight of heart
A
Size of fist
Weighs less than a pound
4
Q
Location of heart
A
Thoracic cavity, between lungs, in inferior mediastinum
5
Q
Apex (pointed tip) is directed toward
A
Left hip and rests on diaphragm
Between junction of 4th and 5th ribs
6
Q
Base of heart points toward
A
Right shoulder
At level of 3rd coastal cartilage
7
Q
Pericardium parts
A
Fibrous pericardium-loose and superficial
Serous membrane
8
Q
Parts of serous heart membrane
A
Parietal pericardium
Visceral pericardium
9
Q
Parietal pericardium
A
Outside layer
Lines inner surface of fibrous pericardium
10
Q
Visceral pericardium
A
Next to heart; aka epicardium
11
Q
Pericardial cavity
A
Space between layers of pericardium. Filled with serous fluid
Fluid helps reduce friction during beating
12
Q
Layers of the heart wall
A
- Epicardium
- Myocardium
- Endocardium
13
Q
Epicardium
A
Outside layer; the visceral pericardium
14
Q
Myocardium
A
Middle layer
Mostly cardiac muscle (only in heart)
15
Q
Endocardium
A
Inner layer aka endothelium
16
Q
Four chamber of heart
A
Atria (right and left)
Ventricles (right and left)
17
Q
Atria
A
TOP (attic)
1.Receiving blood chambers (from system or lungs)
2.Assist with filling ventricles
3. Blood enters under low pressure
18
Q
Ventricles
A
- Discharging chambers
- Thick-walled pumps of heart. (Thicker on left)
- During contraction, blood is propelled into circulation
19
Q
Superior vena cava drains
A
Structures above diaphragm low on O2
20
Q
Inferior vena cava drains
A
Structures below diaphragm low on O2
21
Q
Tricuspid valve
A
Under right atrial chamber where used blood pools.
Blood must pass through to get to right ventricle
Try to make sure it fits righy
22
Q
Which ventricle has thicker myocardium?
A
Left ventricle.
Left ventricle does more work
23
Q
Interatrial septum
A
Separates two atria longitudinally (right and left)
24
Q
Interventricular septum
A
Separates two ventricles longitudinally (right and left)
25
Function of right atrium
Receive blood from vena cava
26
Function of right ventricle
Discharge deoxygenated blood into lungs
27
Left atrium function
Oxygen rich blood flows through pulmonary veins into left atrium
28
Left ventricle function
Discharging chamber
Pumps oxygenated blood to body
29
Heart functions as double pump because
Arteries carry blood away from heart
Veins carry blood toward the heart
30
Pulmonary circuit pump
Right side
Pumps into lungs
31
Systemic circuit pump
Left side
Pumps into entire system
32
Explain pulmonary circulation
1. Blood flows from right side of heart, to lungs, to left side of heart
2. Blood pumped out of right side, through pulmonary trunk, which splits into pulmonary arteries, takes oxygen poor blood to lungs
3. Oxygen rich blood returns to the heart from the lungs via pulmonary veins
33
Systemic circuit
1. Oxygen rich blood returned to left side of heart. Pumped out into the aorta
2. Blood circulates to systemic arteries and to all body tissues .
3. Oxygen poor blood returns to right atrium via systemic veins
Systemic veins empty blood into superior or inferior vena cava
34
Heart valves flow
Only let blood flow in one direction to prevent backflow
35
Atrioventricular valves
Between atria and ventricles
Bicuspid (mitrial) and tricuspid
36
Left AV valve
Bicuspid (mitrial)
37
Right AV valve
Tricuspid valve
38
Semilunar valves
Between ventricle and artery
Pulmonary semilunar valve
Aortic semilunar valve
39
Pulmonary semilunar valve
Between right ventricle and pulmonary trunk
40
Aortic semilunar valve
Between left ventricle and aorta
41
Valves open and close in response to
Pressure changes in the heart
Responsible for pumping of blood
42
Semilunar valve movement
Closed during heart relaxation
Open during ventricular contraction
43
AV valve movement
Open during heart relaxation, when blood passively fills chambers.
Closed during ventricular contraction
44
What anchors AV valves?
Anchors cusps in place by chordae tendinae to the walls of ventricles
45
Made by series of cusps
AV valves
46
Blood in the heart chambers does not
Nourish myocardium
47
The heart has its own nourishing circulatory system made of
Coronary arteries
Cardiac veins
Coronary sinus
48
Coronary arteries
Branch from aorta to supply heart muscle with oxygenated blood
49
Cardiac veins
Drain myocardium of blood
50
Coronary sinus
Large vein on the posterior of heart
Receives blood from cardiac veins
51
Blood empties from heart muscle into the right atrium via
The coronary sinus
Blood re-enters circulation this way
52
Intrinsic conduction system
Cardiac contractions happen independently from nerve impulses
Regular & continous contractions
53
BPM of atrial cells
60
54
BPM of ventricular cells
20 to 40
55
Unifying control system of the heart
Intrinsic conduction system
56
Nodal system
Intrinsic conduction system
57
Which systems regulate heart activity?
Autonomic nervous system (sympathetic: fight or flight )
(Parasympathetic: slow down heart rate)
Intrinsic conduction system
58
What does the nodal system do?
1. Sets, heart rhythm
2. Heart muscle depolarization in one direction (atria to ventricles).
3. Enforces heart rate of 75 BPM
59
Noodle system is made of
Special nervous tissue independent of nervous system
60
Components of intrinsic conduction system
1. Sinoatrial node
2. Atrioventricular node
3. Atrioventricular bundle
4. Purkinje fibers
SAAP
61
Sinoatrial (SA) node
In right atrium
Serves as heart's pacemaker
Starts each heartbeat
62
Atrioventricular (AV) node
1. At junction of atria and ventricles
3.Causes atria to contract
3.Impulse delayed briefly
63
Atrioventricular (AV) bundle, bundle of His and bundle branches are in
Interventricular septum
64
Purkinje fibers
Spread within the ventricle wall muscles
Supply myocardium with contraction impulses
After impulse travels through these blood is ejected from the heart
65
Tachycardia
Rapid heart rate over 100 BPM
66
Bradychardia
Slow heart rate, less than 60 BPM
67
Cardiac cycle
One complete heartbeat
Both atria and ventricles contract and relax
Normally around 0.8 seconds for a complete cycle
68
Systole
Contraction
69
Diastole
Relaxation
70
Average heart rate
75 BPM
71
Ventricular filling aka
Atrial diastole
72
Atrial diastole
1.Heart is relaxed
2. Low heart pressure
3. Open AV valves
4. Blood flows into atria and ventricles
5. Semilunar valves are closed
73
Atrial systole
Ventricles remain in diastole (relaxed)
2. Atrial contract
3. Blood forced into ventricles to complete ventricular filling
74
Isovolumetric contraction
1. Atrial systole ends; ventricular systole begins
2. Intraventricular pressure rises
3.AV valves close
4. For a moment, ventricles are completely closed chambers
75
Ventricular systole (ejection phase)
1. Ventricles continue contracting
2. Intraventricular pressure now surpasses pressure in major arteries leaving heart. (Blood forced from ventricles into arteries)
3. Semilunar valves open (because of increased pressure)
4.Blood ejected from ventricles
5. Atria relaxed and filling with blood
76
Isovolumetric relaxation
1.Ventricular diastole begins
2. Pressure falls below that in major arteries
3. Semilunar valves close
4. For another moment, ventricles are completely closed chambers
5. When atrial pressure increases above intraventricular pressure, the AV valves open
77
Lub
Longer, louder heart sound caused by the closing of the AV valves
78
Dup
Short, sharp heart sound caused by the closing of semilunar valves at the end of ventricular systole
79
Cardiac cycle steps
1. Atrial diastole (ventricular filling)
2. Atrial systole
3.Isovolumetric contraction
4. Ventricular systole (ejection phase)
5. Isovolumetric relaxation
80
Cardiac output
Amount of blood pumped by each side ventricle of the heart in one minute
81
Stroke volume
Volume of blood pumped by each ventricle in one contraction (heartbeat)
82
Normal stroke volume
70 ml pumped out left ventricle with each heartbeat
83
Cardiac output formula
CO=HR(heart rate)(75 beats/min)xSV(stroke volume) (70 ml/beat)
CONVERT TO LITERS (L/min)
84
What percentage of blood in ventricles is pumped with each heartbeat
60%
85
What is the critical Factor controlling stroke volume
How much cardiac muscle is stretched
86
Starling's law of the heart
The more cardiac muscle is stretched,
The stronger the contraction
More blood volume=stronger contraction
87
Important factor influencing the stretch of the heart muscle
Venous return
High blood return, more stretching
88
Factors modifying basic heart rate
1. Neural (ANS) controls
2. Hormones and ions
3. Physical factors
89
1. Neural ANS controls
Sympathetic speeds heart rate
Parasympathetic slows heartrate
90
Hormones and ions role in heartbeat regulation
1.Epinephrine and thyroxine speed heart rate
2.Excess or lack of calcium, Na, and K ions also modify heart activity
91
Physical factors
Age, gender, excercise, body temp influence heart rate
92
Vessels that carry blood away from the heart
Arteries and arterioles
93
Vessels that play a role in exchanges between tissues and blood
Capillary beds
94
Vessels that return blood toward the heart
Venules and veins
95
Tunics of blood vessels except capillaries
1. Tunica intima
2. Tunica media
3.Tunica externa
96
Tunics in capillaries
Tunica intima
97
Tunica intima
Friction reducing lining
Endothelium
In contact with blood
98
Tunica media
Smooth muscle and elastic tissue
Controlled by sympathetic nervous system
99
Tunica externa
Protective outermost covering
Mostly fibrous connective tissue
Supports and protects the vessel
100
Artery is thicker than vein because
Tunica media is much thicker because they help help blood to many tissues
101
Artery vs vein physical differences
Thicker tunica media in artery
Veins have valves
102
Veins and arteries communicate through
Capillaries
103
Aterioles
Branches of larger arteries, get thinner, form network with venules
104
Venules
Branches of veins
105
Capillary beds
Network of thin vessels where arteries meet veins
Capillaries are one cell layer thick
106
Capillaries let
Gases and substances pass through (waste products, nutrients)
107
To withstand changes in pressure, arteries have
Stronger, stretchier tunica media
108
Why do veins have a thinner tunica media?
They operate under low pressure
109
Why do veins have valves?
Prevent backflow of blood
110
Lumen of veins is larger than
That of arteries
111
Skeletal muscle "milks" blood in veins towards
Heart
112
Capillaries
One cell layer thick
Exchanges between blood and tissue
113
Capillary bed parts
Vascular shunt
True capillaries
114
Microcirculation
Blood flow through capillary beds
115
True capillaries
Branch off a terminal arteriole
Empty into post capillary venule
116
Precapillary sphincter
Guards entrance to capillary beds
117
When sphincters are closed blood flows through
Vascular shunt.
From terminal arteriole to post capillary venule
118
Aorta
Largest artery in the body
Leaves from left ventricle of the heart
119
Ascending Aorta
Leaves left ventricle
120
Aortic arch
Arches to left
121
Thoracic aorta
Travels downward through thorax
122
Abdominal aorta
Passes through diaphragm into abdominopelvic cavity
123
Arterial branches of the ascending aorta
Right and left coronary arteries serve the heart O2 rich blood
124
Brachiocephalic trunk splits into the
Right common carotid artery (supplies head)
Right subclavian artery (behind clavicle)
125
Left common carotid artery splits into the
Left internal and external carotid arteries
126
Left subclavian artery branches into the
Vertebral artery
In axilla,
Subclavian artery becomes axillary artery-> brachial artery-> radial and ulnar arteries
127
Arterial branches of thoracic aorta
Intercoastal arteries supply muscles of thorax wall
Other branches supply lungs
Esophagus
Diaphragm
128
Bronchial arteries
Lungs
129
Esophageal arteries
Esophagus
130
Diaphragm
Phrenic arteries
131
First branch of abdominal aorta
Celiac trunk
132
Three branches of celiac trunk
Left gastric artery
Splenic artery
Common hepatic artery (liver)
133
Superior mesentric artery
Supplies most small intestine
Supplies first half of large intestine
134
Left and right renal arteries
Supply kidneys
135
Left and right gonadal arteries
Ovarian and testicular arteries
136
Lumbar arteries
Serve muscles of abdomen and trunk
137
Inferior mesenteric artery
Serves second half of large intestine
138
Left and right common iliac arteries
Final branches of aorta
139
Internal iliac arteries serve the
Pelvic organs
140
External iliac arteries
Enter thigh-> femoral artery -> popliteal artery -> anterior and posterior tibial arteries
141
Which veins drain into the superior vena cava?
1. Radial and ulnar veins-> brachial vein -> axillary vein
2. Cephalic vein
3. Basilic vein drains
4. Basilic and cephalic veins are
5. Subclavian vein
6. Vertebral vein
7. Internal jugular vein
142
Basilic and cephalic veins join at
joined at median cubital vein (elbow area)
143
Basilic vein drains
medial aspect of arm and empties into brachial vein
144
Cephalic vein drains
drains lateral aspect of arm and empties into axillary vein
145
Subclavian vein receives
Blood from arm via axillary vein
Blood from skin and muscles via external jugular vein
146
Vertebral vein drains
Posterior part of head
147
Internal jugular vein drains
Dural sinuses of the brain
148
Left and right brachiocephalic veins receive blood from
Subclavian veins
Vertebral veins
Internal jugular veins
149
Brachiocephalic veins join to form the
Superior vena cava -> Right atrium of heart
150
Azygos vein drains the
Thorax
151
Anterior and posterior tibial and fibial veins drain the
Legs
152
Posterior tibial vein turns into
Popliteal vein
Femoral vein
External iliac vein
153
Great saphenous veins
Longest veins of the body
Receive superficial drainage of the legs
154
Each common iliac vein is formed by
Union of internal and external iliac veins
155
Right Gonadal vein drains into
Right ovary in females
Right testicle in males
156
Left gonadal vein empties into
Left renal vein
157
Left and right renal veins drain
The kidneys
158
Hepatic portal vein drains
The digestive organs.
Travels through liver before it enters systemic circulation
159
Left and right hepatic veins drain the
Liver
160
Arteries that supply most of the cerebrum
Anterior & middle cerebral arteries
161
Internal carotid arteries divide into
Anterior and middle cerebral arteries
162
Vertebral arteries join once within the skull to form
Basilar artery
163
Basilar artery serves
Brain stem and cerebellum
164
Posterior cerebral arteries form from the
Division of the basilar artery
165
Posterior cerebral arteries supply
Posterior cerebrum
166
What unites anterior and posterior blood supplies?
Small communicating arterial branches
167
Circle of Willis or cerebral arterial circle
Complete circle of connecting blood vessels
168
Hepatic portal circulation is made by
Veins draining into digestive organs
Which then empty into hepatic portal vein
169
Hepatic portal vein drains
Digestive organs
Spleen
Pancreas
170
Carries blood to liver where it is processed before returning to systemic circulation
Hepatic portal vein
171
What is absorbed in the first capillary bed?
Nutrients and toxins
172
What happens in the second capillary bed?
Nutrients and toxins leave
173
Arterial pulse
Expansion and recoil of blood vessel wall that occurs as the heart beats
Average healthy pulse at rest 70 to 76
174
Force that causes blood to continue flow
Blood pressure
Force against inner walls of vessels
175
What happens when ventricles contract?
Blood forced into elastic arteries close to heart (Pulmonary arteries, pulmonary trunk, aorta)
Blood flows in descending pressure gradient
176
What happens to pressure in blood vessels as distance from heart increases?
Pressure decreases
177
Explain pressure in different kinds of blood vessels
Pressure is highest in arteries
Lower in capillaries
Lowest in veins
178
Pressure in arteries at peak of ventricular contraction
Systolic
179
Pressure when ventricles relax
Diastolic
180
Indirect method of measuring systemic arterial blood pressure most often in brachial artery
Auscultatory method
181
Blood pressure formula
BP= CO (cardiac output) x PR (peripheral resistance)
182
Peripheral resistance PR
Friction of blood as it passed through vessels
183
Cardiac output CO
Amount of blood pumped out left ventricle per minute
184
Neural factors on blood pressure
Parasympathetic nervous system has little to no effect on BP
Sympathetic nervous system
Promotes Vasoconstriction (narrowing of vessels), which increases blood pressure
185
Kidneys regulate blood pressure by
Altering blood volume
186
If blood pressure is too high, the kidneys
Release water in the urine
187
If blood pressure is too low, what do kidneys do?
Release renin to trigger formation of angiotensin II, a Vasoconstrictor
188
Angiotensin II stimulates release of aldosterone which?
Enhances sodium and water reabsorption by the kidneys
189
Effect of temperature on blood pressure
Heat vasodilates
Cold vasoconstricts
190
effect of chemicals on blood pressure
Epinephrine increases heart rate and blood pressure
191
How does diet affect blood pressure?
Low salt
Low saturated fats
Low cholesterol
Prevents hypertension
192
Causes of increased arterial blood pressure
Decreased blood volume
Exercise
Postural changes
Increased blood viscosity
chemicals
193
Normal Systolic pressure ranges
110 to 140
194
Normal diastolic pressure ranges
70 to 80 mmHg
195
How to identify hypotension?
1.Systolic below 100
2.Associated with illness
3.Warning sign of circulatory shock
196
How to identify hypertension?
Sustained arterial pressure of 140/90 or higher
Warns of increased peripheral resistance
Can damage body and blood vessels
197
Exchange through capillary walls happens because
Concentration gradients
Oxygen and nutrients leave blood and move into tissues
CO2 and other wastes exit tissue cells and enter blood
198
Routes that substances take entering or leaving blood
1. Direct diffusion through membranes
2 Diffusion through intercellular clefts
3. Diffusion through pores of fenestrated capillaries
4. Transport via vesicles
199
Gaps between cells in capillary walls
Intercellular clefts
200
Fluid movement in and out of capillary depends on
Difference between two pressures
201
Role of blood pressure at capillary beds
Forces fluid and solutes out of capillaries
202
Role of osmotic pressure in capillaries
Draws fluid into capillaries
203
Blood pressure is higher than osmotic pressure at the
Arterial end of capillary bed
204
Fluid moves out of the capillary at the beginning of the bed and
Is reclaimed at the opposite venule end
205
When do vessels have a net fluid movement out?
When blood pressure is greater than osmotic pressure
206
When do vessels have a net fluid movement in?
When blood pressure is lower than osmotic pressure
