cardiovascular system Flashcards
1
Q
what does the cardiovascular system contain?
A
the heart and a crossed system of vessels: arteries, veins and capillaries
2
Q
The heart is comprised of two strong __________ ______ and two related ________. One for ____________ and one for ___________ circulation.
A
muscular pumps
arteries
systemic
pulmonary
3
Q
what is the circulation of blood around the body necessary for? (2)
A
- the delivery of oxygen, nutrients and hormones to the body’s cells
- removal of waste products
4
Q
How does the cardiovascular system impact homeostasis?
A
regulation of the cardiovascular system ensures that sufficient blood is provided to all parts or the body whether resting or exercising
5
Q
how must the heart beat to sustain life?
A
continually?
6
Q
Where is the heart located anatomically?
A
in the mediastinum (behind body of sternum) between 2nd and 6th ribs
7
Q
How much does the hearts mass lie on the left and right?
A
2/3 mass left
1/3 right
8
Q
Posteriorly what vertebrae does the heart rest on anatomically?
A
T5 to T8
9
Q
where in the body do we apply pressure when performing CPR? what does this do?
A
lower sternum
compress the heart
10
Q
What does CPR stand for?
A
cardio-pulmonary resuscitation
11
Q
What muscle does the lower part of the heart rest on?
A
the diaphragm
12
Q
What is the lower part of the heart called?
A
the apex
13
Q
what in the body is the apex anchored to? (3) by what? (1)
A
the diaphragm
back of the sternum
the great vessels
by the pericardium
14
Q
what is it called when the heart overlies its boundary (is too large)?
A
cariomegaly
15
Q
Does the heart change shape and size as we grow?
A
yes
16
Q
When does the heart attain adult shape?
A
between puberty and 25 y/o
17
Q
How does the heart take the shape of the chest?
A
it is elongated and transverse
18
Q
How much does the heart weigh in men?
A
310 g
19
Q
How much does the heart weigh in women?
A
225g
20
Q
What is the name of the loose sac covering the heart?
A
the pericardium
21
Q
What is the external surface of the pericardium called?
A
the fibrous pericardium
22
Q
What is the fibrous pericardium like? (3)
A
tough
loose fitting
inelastic sac
23
Q
What is the internal layer of the pericardium called?
A
the serous pericardium
24
Q
What are the two layers of the serous pericardium called?
A
the parietal layer
the visceral layer
25
What is in-between the parietal layer and the visceral layer of the serous pericardium?
pericardial fluid
26
What does the parietal layer of the serous pericardium line?
it lines the fibrous pericardium
27
what does the visceral layer of the serous pericardium adhere to?
the outside of the heart
28
What is the function of the coverings of the heart? (2)
protection against friction
Heart remains free to move in the lubricated, loose covering
29
What is the role of the fibrous pericardium? (3)
1. protection from infections and physical damage
2. Anchoring to surrounding structures
3. prevents overfilling due to rigid nature
30
What are the three distinct layers that make up the heart wall from external to internal?
1. epicardium
2. Myocardium
3. Endocardium
31
What is the epicardium?
the outermost layer of the heart wall
32
What is the epicardium also known as?
the visceral layer of the pericardium
33
What is the epicardium composed of?
connective tissue and fat
34
What does the epicardium secerete a small amount of? where?
a small amount of fluid into the pericardial cavity
35
What is the myocardium? what is it made of?
the middle layer and thickest part of the heart wall made up of cardiac muscle tissue
36
what is the muscle tissue in the myocardium responsible for?
contractions in the heart
37
Where is the myocardium the thickest? why?
by the left ventricle so it can pump oxygenated blood through the body.
38
What is the endocardium? what is it made of?
the innermost layer of the heart made up of smooth muscle and elastic fibres
39
what does the endocardium help to regulate?
heart contracts and a smooth surface for blood flow
40
What does the endocardium line?
the innermost chambers of the heart and covers the heart halves
41
How many main chambers of the heart are there?
4
42
What are the two upper chambers of the heart called?
atria/atrium
43
what are the two lower chambers of the heart called?
ventricles
44
what are the left and right chambers of the heart separated by?
an extension of the heart wall called the septum
45
what are the atria known as?
the receiving chambers
46
what is the function of the right atrium?
to receive deoxygenated blood from the veins and deliver it to the right ventricle
47
what is the function of the left atrium?
to receive oxygenated blood from the veins and deliver to the left ventricle
48
why are the atria thin walled?
because they only need to pump the blood a short distance to the corresponding ventricle
49
What are the auricles?
a flap located in both atria which allows for the overall blood to be expanded in each atrium
50
how do Auricles manage the volume of blood entering the atria?
they work like reservoirs, temporarily storing blood and help to modulate blood pressure fluctuations
51
What are the two types of valves in the heart?
Atrioventricular (AV) valves
Semilunar (SL) Valves
52
Where are the AV valves located?
at the openings between the atria and ventricles
53
Where are the SL valves located?
where the pulmonary artery and the aorta arise from the right and left ventricles respectively
54
What is the name of the left AV valve?
the mitral valve
55
what kind of valve is the left AV valve?
a biscupid valve because it has two flaps
56
What is the proper name for the flaps in the valves?
cusps
57
What kind of valve of the right AV valve? why?
a triscupid valve because it has 3 flaps
58
Where is the right AV valve located?
between the right atrium and right ventricle
59
The AV valves allow the blood to flow from ______ to ventricles but not back into the _____.
atria
atria
60
What does the ventricular pump force the valves to do? where does this send the blood?
close
into the pulmonary artery and aorta
61
How many semilunar valves are there?
2
62
What are the names of the 2 semilunar valves?
pulmonary semilunar valve
aortic semilunar valve
63
What is the function of the semilunar valves?
to prevent the back flow of blood from the arteries back into the ventricles
64
what is the skeleton of the heart made of?
a set of connected fibrous rings which support the heart valves
65
What does the fibrous skeleton of the heart serve as an attachment point to?
the myocardium
66
what kind of barrier does the skeleton of the heart provide?
an electrical barrier between the myocardium of the atrium and of the ventricles
67
what are the two largest veins in the body?
The superior and inferior venae cavae
68
In the first step of blood flow through the cardiovasular system, what happens?
the superior and inferior venae cave empty their contents into the right atrium
69
In the second step of blood flow, what happens to the blood that is in the right atrium?
the blood passes via the right atrioventricular valve into the right ventricle
70
In the third step of blood flow, what happens to the blood in the right ventricle?
it is pumped into the pulmonary artery or trunk
71
What is the only artery in the body that carries deoxygenated blood?
the pulmonary artery or trunk
72
what is the opening of pulmonary artery guarded by? what is it made of
the pulmonary valve formed by three semilunar cusps
73
In the fourth step of blood flow, where does the blood go after the pulmonary artery?
the pulmonary artery leaves the heart and divides into the left and right pulmonary arteries which carry the deoxygenated (venous) blood to the lungs
74
In the fifth step of blood flow, what happens to the blood in the lungs?
the exchange of gasses takes place CO2 is excreted and O2 is absorbed
75
In the sixth step of blood flow, what happens to the blood after the gasses exchange?
Two pulmonary veins from each lung carry oxygenated blood back to the left atrium
76
In the seventh step of blood flow, what happens to the blood when it is in the left atrium?
blood passes through the left atrioventricular valve into the left ventricle
77
In the eighth step of blood flow, what happens to the blood once it is in the left ventricle?
it is pumped into the aorta, the first artery of general circulation
78
Which artery branches off the aortic artery to supply the heart with oxygen? what do they form?
the right and left coronary arteries that form into smaller branches to alternate routes
79
what do the small coronary veins that supply the heart do?
drain the deoxygenated blood directly into the right atrium via the coronary sinus
80
When there is a clot or thrombus in the smaller branches of the arteries that supply the heart what happens?
a heart attack
81
What are the symptoms of a heart attack? (5)
chest pain
sweating
shortness of breath
fatigue
syncope (fainting)
82
What side of the heart returns oxygenated blood to the lungs?
right side
83
what side of the heart delivers oxygenated blood throughout the body?
left side
84
in the conduction system of the heart, what are the four major structures?
sinoatrial node
atrioventricular node
bundle of His
Purkinje fibres
85
What is the role of the sinoatrial node?
pacemaker, it initiates action potential that results in an electrical impulse that spreads through the left and right atria, causing it to contract
86
in the conduction system of the heart, what is the sinoatrial node?
a bundle of hundreds of cells situated in the right atrial wall near the opening of the superior vena cava
87
in the conduction system of the heart, what is the role Atrioventricular node?
the gatekeeper between the atria and ventricles located in the right atrium at the interatrial septum
88
in the conduction system of the heart, what is the atrioventricular node made of?
a small mass of special cardiac fibres
89
in the conduction system of the heart, What is the role bundle of His?
a collection of cells
90
where does bundle of his extends to?
it extends from the AV node in two branches on the sides of the inter ventricular wall
91
what does the bundle of His do?
carries electrical signals from the AV node to the bundle branches
92
what do the purkinje fibres do?
send signals to the ventricles so they rhymically contract
93
where are the purjinke fibres located?
they are continuous with AV bundles and attach to the apex of the heart.
94
what do the bundle branches do in the conduction system?
they spread the electrical signals throughout the left and right ventricles which causes the ventricles to contract
95
Which of the nodes in the conduction system initiates the action potential?
the sinoatrial node
96
Where does the action potential travel once the sinoatrial node initiates it?
it travels to the atria and then to the AV node
97
where does action potential go once it reaches the AV node?
down to the ventricles via the bundle of his and punjinke fibres
98
When there is a problem with the senatorial node, how can the heart compensate via the AV node?
the AV node can take over as a secondary pacemaker, although it is slower (bradycardia)
99
What is slow heart rate called?
bradycardia
100
When the sinoatrial node has a problem, how can the atria or ventricles compensate?
the atria or ventricles can generate their own electrical impulses to sustain rhythm however they are often less efficient
101
When there is a problem with the sinoatrial node, how can the nervous system compensate?
the sympathetic nervous system can increase the nervous system activity to simulate the heart and increase heart rate
102
when the sinoatrial node has a problem, how can medical intervention help?
a pacemaker can be used if the body cannot compensate well enough
103
What is systole?
a single heart contraction
104
What is diastole?
a single heart relaxation
105
what are the 5 steps of the cardiac cycle (one heartbeat)?
1. atrial systole (contraction)
2. Isovolumetric ventricular contraction
3. Ejection
4. Insovolumetric ventricular relaxation
5. Passive ventricular filling
106
what happens in atrial systole?
the atria contracts and empties, the relaxed ventricles fill with blood
107
What happens in isovolumetric ventricular contraction?
the initial contraction of the ventricle and the opening of the semilunar valves, blood volume remains the same
108
What happens during ejection?
ventricle pressure is higher than artery pressure so blood passes through the semilunar valves
109
What happens during is-volumetric ventricular relaxation?
semilunar valves close and AV valves open
110
What happens during passive ventricular filling?
There is an increase in atrial pressure due to the influx of venous blood which causes the ventricles to fill with blood
111
what is blood pressure?
the force of your blood pushing against the walls of your arteries and your heart pumps it around your body
112
what is systolic blood pressure?
The higher number that measures the pressure in the arteries when the heart beats (ventricular systole) so the 120/
113
What is Diastolic pressure?
This is the lower number and measures the pressure in your arteries when your heart is resting (ventricular diastole) between beat so the /80
114
What is normal blood pressure?
120/80
115
What is hypertension blood pressure?
120-139/80-90
116
what is high blood pressure in hypertension stage 1?
140-159/90-99
117
What is high blood pressure is hypertension stage 2?
160+/100+
118
What is blood pressure in hypertensive crisis?
180+/110+
119
what is the unit measurement of blood pressure?
mmHG (millimetres of mercury)
120
what are three things that affect blood pressure?
cardiac output
resistance of the vessels
hormones
121
which nerve can affect heart rate?
the 10th cranial nerve
122
what are the carotid reflexes?
pressure reflexes in the neck which communicate with the brain
123
How do carotid reflexes affect blood pressure?
they detect a rise in blood pressure and send nerve impulses that activate the parasympathetic nervous system (calms us) so lowers BP
124
how does the aortic reflex affect blood pressure?
it detects a rise in BP and communicates with the brain to decrease heart rate
