Functions Of The Heart Flashcards
(140 cards)
0
Q
The heart is located in the thoracic cavity between the lungs. What is this area called?
A
Mediastinum
1
Q
What cavity is the heart located?
A
Thoracic
2
Q
What membrane encloses the heart?
A
Pericardial
3
Q
What are the 3 layers of the pericardial membrane?
A
Fibrous pericardium
Parietal pericardium
Visceral pericardium
4
Q
Which pericardium membrane is the outermost?
A
Fibrous
5
Q
Which pericardium layer lines the fibrous pericardium
A
Parietal
6
Q
Which pericardial later is on the surface of the heart muscle?
A
Visceral
7
Q
What is the other name for visceral pericardium
A
Epicardium
8
Q
What lies beneath the parietal and visceral areas that prevents friction when the heart beats
A
Serous fluid
9
Q
What is cardiac muscle called
A
Myocardium
10
Q
What are the unit of contraction and contain the proteins myosin actin and troponin
A
Sarcomeres
11
Q
What lines the chambers of the heart
A
Endocardium (simple squamous epithelium)
12
Q
The lining of the vessels
A
Endothelium
13
Q
What important physical characteristic does the endocardium have
A
Smoothness
14
Q
What does the smoothness of the endocardium prevent
A
Blood clots
15
Q
What are the 2 upper chambers of the heart
A
Atria
16
Q
What are the 2 Lower chambers of the heart
A
Ventricles
17
Q
Which walls of the heart are thinner
A
Atria
18
Q
What wall separates the atria
A
Interatrial septum (made of myocardium)
19
Q
What wall separates the ventricles
A
Interventricular septum
20
Q
Which wall receive blood
Which walls pump blood
A
Atria
Ventricles
21
Q
What veins return blood from the body to the right atrium
A
Cabal veins
22
Q
What carries blood from the upper body
What carries blood from the lower body
A
Superior vena cave
Inferior
23
Q
What valve will blood flow thru from the right atrium into the right ventricle
A
Right atrioventricular valve (tricuspid)
24
From where does the left atrium receive blood
| By way of what veins
Lungs
| Pulmonary
25
What valve does the blood flow through from the left atrium to the left ventricle
Left atrioventricular valve (bicuspid)
26
Hat hormone does the atrium produce for BP maintenance
Atrial natriuretic peptide ANP
27
What valve lies at the junction of the pulmonary artery and right ventricle
Pulmonary semilunar valve
28
What type of muscles lie in the lower portion of the right ventricle
Papillary
29
What fibrous connective tissue extends from the papillary muscles (in right ventricle) to the flaps of the tricuspid valve
Chordae tendineae
30
What does the chordate tendineae prevent
Inversion of the tricuspid valve
31
What is the largest artery of the body
Aorta
32
Which ventricle pumps blood to the body through the aorta
Left ventricle
33
What valve lies at the junction of the aorta and the left ventricle
Aortic semilunar valve
34
What are the first branches of the ascending aorta just beyond the aortic semi lunar valve
Right and left coronary artery's
35
The two arteries branch into smaller arteries and arterioles then into what
Capillaries
36
What do the coronary capillaries do
They merged to form coronary veins which empty blood into a large coronary sinus that returns blood to the right atrium
37
What is the purpose of the coronary vessels
To supply blood to the myocardium because oxygen is essential for normal myocardial contraction
38
If a coronary artery becomes obstructed by a blood clot what happens to the myocardium
It becomes a ischemic (deprived of blood supply)
39
What will prolonged ischemia create
And infarct which is an area of necrotic tissue
40
What is the name for a heart attack
Myocardial infarction
41
What is the sequence of events in one heartbeat
The cardiac cycle
42
What is another term for contraction
Systole
43
What is the term for relaxation
Diastole
44
Does atrial or ventricular systolic start first
Atrial systole is followed by ventricular systole
45
Is atrial systole or ventricular systole longer
Ventricular
46
What causes the loudest and longest sound in the lub-dub which is the first sound
It is caused by ventricular systole closing the AV valves
47
The second sound in the lub-dub is caused by what
It is caused by the closure of the aortic and pulmonary semi lunar valves
48
If a valve does not close properly there is an extra sound and this is called what
A heart murmur
49
What is the serous membrane on the surface of the myocardium
Epicardium
50
What is the heart muscle which forms the walls of the four chambers
Myocardium
51
What is the endothelium that lines the chambers and covers the valves it is smooth to prevent clotting
Endocardium
52
What receives deoxygenated blood from the body by way of the superior and inferior or Caval veins
Right atrium
53
What is the right AV valve that prevents backflow of blood from the RV to the RA when the RV contracts
Tricuspid valve
54
What pumps blood to the lungs by way of the pulmonary artery
Right ventricle
55
What prevents backflow of blood from the pulmonary artery to the right ventricle when the right ventricle relaxes
Pulmonary semi lunar valve
56
What receives oxygenated blood from the lungs by way of the four pulmonary veins
Left atrium
57
What is the left baby valve which prevents backflow of blood from the left ventricle to the left atrium when the left ventricle contracts
Mitral valve
58
What pumps blood to the body by way of the aorta
Left ventricle
59
Prevents the back for blood from the awarded to the left ventricle when the left ventricle relaxes
Aortic semilunar valve
60
What is in both the right ventricle on my friend to go and prevents inversion of the AV valves when the ventricles contract
Papillary muscles and Chordae tendineae
61
What is the fibrous connective tissue that Anchors the four heart valves prevents enlargement of the valve openings and electrically insulates the ventricles from the atria
Fibrous skeleton of the heart
62
What is the most common cause of coronary artery disease
Atherosclerosis
63
What is atherosclerosis
When plaques of cholesterol and inflammatory cells form in the walls of a coronary artery
64
What enzymes do we have jeans for that are involved in cholesterol metabolism
Liver enzymes which regulate the transport of cholesterol in the blood in the form of lipoprotein's and regulate delivers excretion of excess cholesterol and bile
65
What is believed to exert a protective effect by lowering blood lipid levels and women
Estrogen
66
What chemical markers in the blood signal the presence of inflammation
Homocysteine and C-reactive protein CRP
67
With coronary artery bypass surgery which vein is grafted around the obstructive coronary vessels to restore blood flow to the myocardium
Saphenous vein of the leg
68
What is the natural pacemaker of the heart
Sinoatrial SA node which are a group of cardiac muscle cells in the wall of the right atrium just below the opening of the superior vina cava
69
Why is the SA node considered specialized
Because it has the most rapid natural rate of contraction it depolarizes more rapidly than any other part of the myocardium
70
The cells of the SA node more permeable to what Ions then any other cardiac muscle cells
NA+ therefore they depolarize more rapidly than contract and initiate each heartbeat
71
From the SA node impulses for contractions travel to what node
The atrioventricular AV node
72
What does the transmission of impulses from the SA node to the AV node into the rest of the atrial myocardium bring about
Atrial systole
73
What connected tissue exes and electrical insulation between the two sets of Chambers including the atrium myocardium in the ventricular myocardium
The fibrous connective tissue
74
What is the only pathway for impulses from the atria to the ventricles
The atrioventricular bundle AV bundle also called the bundle of His
75
Where is the AV bundle located
Within the upper interventricular septum
76
Where does the AV bundle receive impulses from
The AV node and then transmits them to the right and left bundle branches
77
From the bundle branches the impulses travel along ______to the rest of the ventricular myocardium and bring about ventricular systole
Purkinje fibers
78
What test shows the electrical activity of the atria and ventricles
Electrocardiogram ECG
79
If the SA node does not function properly what will initiate the heart beat
The AV node will at a slower rate
80
What is also capable of generating the Beat of the ventricles at a much lower rate of 15 to 40 bpm
The AV bundle
81
What is an irregular heartbeat
Arrhythmia
82
What is a very rapid and on coordinated ventricular beats that is totally ineffective for pumping blood
Ventricle fibrillation
83
A normal resting heart rate or pulse of 60 to 80 beats per minutes is the rate of depolarization of what node
SA node
84
The SA node actually has a slightly faster rate which is closer to 100 bpm but it is slowed by what nerve impulses
Parasympathetic nerve impulses
85
What is a heart rate of less than 60 called
Bradycardia
86
What is a prolonged are consistent rate greater than 100 bpm called
Tachycardia
87
What is the amount of blood pumped by a ventricle in one minute
Cardiac output
88
Why is a certain level of cardiac output needed at all times
To transport oxygen to tissues and to remove waste products
89
What is the term for the amount of blood pumped by A ventricle per beat
And what is the average resting stroke volume Pwe beat
Stroke volume
| 60 to 80 mL
90
What formula enables us to determine cardiac output
Cardiac output = stroke volume X pulse (heart rate)
91
What is the normal average resting cardiac output
5 to 6 L per minute
92
The increase in stroke from him is the result of _____________, which states that the more the cardiac muscle fibers are stretched the more forcefully the contract
Starlings law of the heart
93
During exercise more blood returns to the heart this is called
Venous return
94
Increased venous return will stretch what
The myocardium of the ventricles
95
What is the percent of the blood in her ventricle that is pumped during systole. Which is another measure of the health of the heart
Ejection fraction
96
What percentage of blood does a ventricle empty when it contracts
60 to 70% a lower percentage would indicate that the ventricle is weakening
97
What part of the brain contains the two cardiac centers
The Medulla
98
What are the two cardiac centers of the medulla
Excelerator center and the inhibitory center
99
What does the Excelerator center and the inhibitory center do
Send impulses to the heart along autonomic nerves
100
What are the two divisions of the autonomic nervous system
Sympathetic and parasympathetic
101
The sympathetic impulses from the Excelerator center along sympathetic nerves do what
Increased heart rate and tons of contraction during exercise and stressful situations the (neurotransmitter is norepinephrine)
102
The parasympathetic impulses from the inhibitory center along the biggest nerves do what
Decreased heart rate (the neurotransmitter is acetylcholine)
103
What information is received by the middle like to initiate changes
Because the heart pumps blood is essential to maintain normal blood pressure. Blood contains oxygen which all tissues must receive continuously. Therefore changes in blood pressure and oxygen level of the blood or stimuli for changes in heart rate
104
What are Pressoreceptors
They are in the carotid senses and a word exciting ee which detect changes in blood pressure
105
What are chemo receptors
They are in the carotid bodies and they were dick body which she took changes in the oxygen content of the blood
106
What are the sensory nerves for the carotid receptors
Glossopharyngeal nerve's (9th cranial)
107
What are the sensory nerves from the Aortic arch receptors
Vegas (10th cranial) nerves
108
Generated by the SA node through the conduction pathway; parasympathetic impulses (Vegas nerves) decrease the rate; sympathetic impulses increase the rate
Heart rate
109
The amount of blood pumped by ventricle in one beat
Stroke volume
110
The volume of blood pumped by ventricle in 1 minute; stroke volume X pulse
Cardiac output
111
The percentage of blood within the ventricles is pumped out per beat
Ejection fraction 60% to 70%
112
The difference between resting cardiac output and Maximum cardiac output during exercise
Cardiac reserve 15 liters or more
113
What detects a drop in blood pressure
The pressoreceptors in the carotid sinuses
114
What occurs when a drop in blood pressure takes place and is detected by the receptors in a carotid sinuses
The impulses travel along the glossopharyngeal nerve to the medulla and the decrease in the frequency of impulses stimulates the Accelerator center
115
When the Accelerator generates impulses they are carried by what nerves and to where
They are carried by the sympathetic nerves to the SA node AV node and ventricular myocardium
116
To correct hypoxemia the reflex arc would be what five things
1. Aortic chemoreceptors 2.Vegus nerve sensory, 3 Accelerator Ctr. in the medulla 4. sympathetic nerves, and 5. the heart muscle, which will increase its rate and force of contraction to circulate more blood
117
What hormone is secreted by the adrenal and Medulla in stressful situations
Epinephrine
118
What is a factor of epinephrine
To increase heart rate and force of contraction. This will help supply more blood to tissues in need of more oxygen
119
Which chamber of the heart works harder with high blood pressure
The left ventricle
120
Elite ventricle is not an efficient pump and such weakness may progress to ______
Congestive heart failure
121
A heart valve that becomes thick and by fibrosis can lead to _____ and ______
Heart murmurs and less efficient pumping
122
Contraction of cardiac cells and balls action potentials at the cell membrane and the sliding of ____ and ____
Myosin and actin in sarcomeres
123
What is an arterioles
And arteriole is a small artery
124
What happens in a cardiac cycle
A sequence of events in one heartbeat in which a simultaneous contraction of the Atria is followed by a simultaneous contraction of the ventricles
125
What is the epicardium
The serous membrane on the surface of the myocardium
126
What is the pericardium
A sack which includes three membranes and encloses the heart
127
What is the pulmonary circuit
The vessel pattern in the lungs were oxygen and CO2 are exchanged
128
What is vasoconstriction
The decreased diameter of the vessel due to contraction of smooth muscle in the wall
129
What is the endothelium
The endothelium is the simple Squam us epithelium cells lining A vein or artery
130
What is the Tunica media
Middle layer of an artery or vein
131
Where are the centers. That regulate heart rate located
Medulla
132
What vessel does the left ventricle pumps blood into
Aorta
133
What prevents backflow of blood from the ventricles to the atria
Mitral and tricuspid valve
134
What do the kidney secrete when blood pressure decreases
Renin
135
What is the layer of the walls of arteries and veins that is smooth to prevent abnormal clotting
Lining, made of simple Squamous epithelium
136
What prevents backflow from the arteries to the ventricles
Aortic and pulmonary semilunar valves
137
What is the function of the serous fluid of the pericardial membranes
Prevent friction as the heart beats
138
Why does epinephrine increase blood pressure
It increases heart rate and force
139
What are the steps the blood flows through the heart
1. oxygen poor blood flows from the body into the right atrium
2. Blood flows through the right atrium into the right ventricle
3. The right ventricle pumps the blood to the lungs where the blood releases waste gases and pics of oxygen
4. The newly rich oxygen blood returns to the heart and enters the left atrium
5. Blood flows through the left atrium into the left ventricle
6. The left ventricle pumps oxygen-rich blood to all parts of the body
