Cardiovascular system Flashcards
1
Q
As you inhale and expand the rib cage, what happens to the air pressure in the lungs?
A
Decrease in pressure because expanded rib cage increases the volume with the same amount of air, therefore movement of air is all about pressure difference
2
Q
Blood composition
A
Formed elements and plasma
3
Q
Formed elements
A
erythrocytes, leukocytes, platelets
4
Q
erythrocytes
A
Red blood cells
5
Q
Leukocytes
A
white blood cells
6
Q
Platelets
A
activated in immune defense mechanisms to form a plug to prevent blood loss
7
Q
arterial blood
A
blood leaving the heart, oxygenated except the artery that goes into the lungs
8
Q
venuous blood
A
blood returning to the heart, generally less oxygenated except the blood going from lungs to heart
9
Q
Blood is
A
8% of body weight
10
Q
How many liters of blood is there?
A
~5L
11
Q
plasma
A
straw-colored liquid consisting of water and dissolved solutes, major solute, in terms of concentration is Na+
12
Q
Functions of the blood
A
- Transportation all of the substances essential for cellular metabolism are transported by the circulatory system.
*Respiratory- RBC, transport O2 from inhaled air attaching itself to hemoglobin molecules within the RBC during aerobic respiration. CO2 produced by cell respiration is carried by the blood to the lungs for elimination in the exhaled air.
*Nutritive- digestive system is responsible for the mechanical and chemical breakdown of food so that it can be absorbed through the intestinal wall into the blood and lymphatic vessels. Blood carries these absorbed products of digestion through the liver to the cells of the body
*Excretory-metabolic wastes (like urea), excess water and ions, and other molecules not needed by the body are carried by the blood to the kidneys and excreted in the urine. - Regulation
*Hormonal- blood carries hormones from their site of origin to distant target tissues where they perform a variety of functions
*Temperature-aided by the diversion of blood from deeper to mores superficial cutaneous vessels or vice versa.
Hot outside- blood is diverted from deep to superficial to help cool the body.
Cold outside- blood is diverted to deeper vessels to help warm - Protection
*Clotting- the clotting mechanism protects against blood loss when vessels are damaged
*Immune- WBC protect against many disease causing agents (pathogens)
13
Q
Hematopoiesis
A
process by which blood cells are being formed constantly, making about 500 billion RBC/day
14
Q
Hematopoietic stem cells originate where, and end where in the fetus and then migrate where shortly after birth?
A
In the yolk sac of the human embryo and then migrate in sequence to regions around the aorta, to the placenta, and then to the liver of the fetus. But then migrate to the bone marrow shortly after birth.
15
Q
Erythropoiesis
A
Formation of erythrocytes (RBCs)
16
Q
Leukopoiesis
A
Formation of leukocytes (WBCs)
17
Q
Myeloid tissue
A
Red bone marrow of the long bones, ribs, sternum, pelvis, bodies of the vertebrae, and portions of the skull
18
Q
Lymphoid tissue
A
Lymph nodes, tonsils, spleen, thymus,
19
Q
Bone marrow produces
A
all the different blood cell types
20
Q
Process of differentiation of a blood cell
A
As the cells become differentiated during erythropoiesis and leukopeisis, they develop membrane receptors for chemical signals that cause further development along particular lines
21
Q
Earliest cells that can bbe distinguished under a microscope
A
erythroblasts, myeloblasts, lymphoblasts, and monoblasts
22
Q
Erythropoietin
A
Secreted by the kidneys, stimulates erythropoiesis, increasing the number of RBCs
23
Q
stimulates erythropoietin production from kidneys
A
tissue hypoxia
deprivation of oxgygen, or low blood oxygen levels
24
Q
At high altitudes
A
Lower pO2 in the air, so this stimulates the production of erythropoietin from the kidneys, leading to more RBCs
25
Process of erythropoeisis
The erythropoietin-stimulated cell undergoes cell division and differentiation, leading to the production of erythroblasts, which transform into normoblasts, which lose their nuclei to become reticulocytes, and which change into fully mature erthrocytes, takes 3 days
26
Type A Blood
Has A antigens, and anti-B antibodies
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Type B Blood
Has B antigens, and anti-A antibodes
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Type AB Blood
Has both A and B antigens, and no antibodies, making them the universal recipient
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Type O Blood
Has neither A nor B antigen, and both anti-A and anti-B antibodies, making them the universal donor
30
Lymphocytes in the immune system
Secrete a class of proteins called antibodies that bond to specific antigens
31
Rh factor
Another group of antigens found on the RBCs of most people (Rh + or Rh -)
32
Hemostasis (Clotting)
Vasoconstriction, platelet plug, production of fibrin
33
Clotting and vasoconstriction
to cause regional blood constriction, local immediate response to injured vessel
34
Platelet plug
Platelet activation by vessel injury and adhere to von Willebrand factor, secreted by endothelial cells
35
What does the Von Willebrand factor do?
binds to both collagen and the platelets, which help form the platelet plug during the clotting process.
36
Fibrin
Produced from plasma chemical cascade that involves thrombin converting fibrinogen to fibrin
37
Fibrin is degraded by
Plasmin (enzyme derived from Plasminogen
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Plasmin is derived by
Plasminogen
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Plasmin degrades
Fibrin
40
tPA (tissue Plasminogen activator), when given at the very beginning of a stroke, can reduce the extent of brain damage due to blockage of blood flow. Explain how tPA works.
tissue Plasminogen activator, turns on plasmin which degrades fibrin. Fibrin helps join platelets together and strengthen platelet plug, so by turning off fibrin, this turns off the platelet plug mechanism thus minimizing the blockage and leading to less brain damage because this leads to a less blockage of blood flow.
41
Blood clotting general mechanism
When a blood vessel is injured and the endothelium is broken, glycoproteins in the platelet’s plasma membrane are now able to bind to the exposed collagen fibers. The force of blood flow might pull the platelets off the collagen, however, were it not for another protein produced by endothelial cells known as von Willebrand’s factor, which binds to both collagen and the platelets, activating a signaling cascadeto produce a platelet plug in the damaged vessel.
42
arteries
largest vessels leading away from the heart, made up of smooth muscle
43
arterioles
a bit smaller, at the beginning of organs branch into capillaries, made up of smooth muscle
44
Capillary beds
play a role in exchanging nutrients, help regulate blood pressure, and play a role in thermoregulation. Exchange of O2 and CO2 and other nutrients and waste products occurs here.
Lined with endothelial cell walls, because they're smooth and frictionless, allowing blood to flow easily
45
Venuoles
the smallest vein component that suck blood out of the capillaries, merge into the larger veins, has valves that don't prevent gravity to change direction of blood flow
46
Veins
carry back deoxygenated blood, contain most of the blood volume, low pressure, has valves that prevent the blood from flowing backwards leading to vericose veins or hemmorhoids
47
Kidnery has
fenestrated capillary beds to filter larger and bulk flow
48
Kidnery has
fenestrated capillary beds to filter larger and bulk flow
49
How many capillaries
40 billions, surface area 1000mi^2
50
Lymphatic system components
Vessels, ducts, nodes
51
lymphatic system basic functions
1. it transports interstitial (tissue) fluid, initially formed as a blood filtrate, back to the blood
2. transports absorbed fat from the small intestine to the blood
3. its cells- called lymphocytes- help provide immunoogical defenses against disease-causing agents (pathogens)
52
What happens when the circulation of the lymphatic system is blocked by a tumor in a lymph node?
You get lymphoma, edema- localized gathering of fluid, because can't be filtered and returned. You have to remove the whole node.
53
Cardiac muscle
striated, skeletal muscle, organized array of actin & myosin, each cell has it's own nucleus, and connected with a gap junction, acts as one functional syncytium
54
Gap junctions
intercalated disks, described before names, connect cells end to end
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desmosomes
knit them together cardiac tissue is strong, sturdy, and solid
56
Cardiac muscle
striated, skeletal muscle, organized array of actin & myosin
57
myocardial cells
each has it's own nucleus connected with a gap junction
58
Pacemaker cells
SA node, AV node (bundle of His) and Purkinje fibers
59
Sympathetic activity
increases rate of diastolic depolarization via cAMP
60
Parasympathetic activity
decreases rate of diastolic depolarization via opening Ca2+ channels
61
AV node
atrioventricular node, located on the inferior portion of the interatirial septum
62
Conducting tissues of the hert
Action potentials that originate in the SA node spread to adjacent myocardial cells of theright and left atria through the gap junctions between these cells. Because the myocardium of the atria is separated from the myocardium of the ventricles by the fibrous skeleton of the heart, however, the impulse cannot be conducted directly from the atria to the ventricles. Specialized conducting tissue composed of modified myocardial cells is thus required. These specialized myocardial cells form the AV node, bundle of His, and Purkinje fibers.
63
Action potential spreads
From the SA node, through the atria, pass into the atrioventricular node (AV node), which is located on the inferior portion of the interatrial septum. From here, action potentials ocntinue through the atrioventricular bundle or bundle of His, beginning at the top of the interventricular septum. This conducting tissue pierces the fibrous skeleton of the heart and continues to descend along the inter ventricular septum. The atrioventricular bundle divides into right and left bundle branches, which are continuous with the Purkinje fibers within the ventricular walls. Within the myocardium of the ventricles, the action potential spreads from the inner (endocardium) to the outer (epicardium) side. This causes both ventricles to contract simultaneous and eject blood into the pulmonary and systemic circulations.
64
blood flows
Deoxygenated blood flows from the organs through the valved veins through the superior and inferior venacava returning to the right atrium, through the tricuspid valve or the atrioventricular valve (AV valve) which
65
AV valve
tricuspid valve or the atrioventricular valve is located between the right atrium and right ventricle. Has three flaps. Allows blood to flow from the atria to the ventricle, butnormally prevent backflow of blood into the atra. Opening and closing of these valves occurs as a result of pressure differences between the atria and ventricles.
66
Ventricles are relaxed the blood flows where, due to the AV valve
the return of blood to the atria causes the pressure in the atria to exceed thatinthe ventricles, causing the AV valves to open, allowing blood to enter the ventricles
67
Ventricles contract AV valve does what?
the Intraventricular pressure rises about the pressure in the atria and pushes the AV valves close
68
Semilunar valves
pulmonary valve
| located at the origin of the pulmonary artery and aorta
69
When do the semilunar valves open?
They open during ventricular contraction, allowing blood to enter the pulmonary and systemic circulations.
70
When do the semilunar valves close?
During ventricular relaxation, when the pressure in the arteries is greater than the pressure in the ventricles, snapping them shut, preventing the backflow of blood into the ventricles.
71
Ventricular contraction
systole
72
Ventricular relaxation
Diastole
73
Mitral valve
Bicuspid valve prevents backflow of blood from the left ventricle to the left atrium.
74
Diastole, what valves are open?
tricuspid and bicuspid valves are opened, so blood flows from atrium to
75
Systole
SA node conducts
76
Ventricular systole begins when
ventricles are filled with blood
77
When do the semilunar valves open?
When blood in the ventricles are increasing the pressure causing the AV and the mitral valve to close, opening these valves so that blood flows thru the pulmonary artery and aorta
78
SA node
Sinoatrial node, where electrical impulses begin, causing your heart to contract. Sometimes referred to as your heart's "natural pacemaker"
79
What causes the heart to contract?
The beating of the heart is regulated by electrical impulses generated by your heart muscles.
80
What is the pathway of electrical impulse?
Sinoatrial node to the atrioventricular node, where signal is checked and then sent through the ventricles which causes them to contract. Your heart rate can changed based on diet stress or hormones.
81
What is the pathway of electrical impulse?
Sinoatrial node to the atrioventricular node, where signal is checked and then sent through the ventricles which causes them to contract. Your heart rate can changed based on diet stress or hormones.
82
Ventricular systole
relaxation of the atria
83
Ventricular diastole
Contraction of the atria occurs in the last 0.1 second of this period
84
End-diastolic volume
the total volume of blood i the ventricles as the end of diastole, so after contraction
85
Stroke volume
the volume of blood that comes out of one heart beat ~70-80 mL in a young man
86
Contraction of the ventricles in systole
ejects about 2/3 of the blood they contain, sv, leaving 1/3 of the intial amount left in the ventricles as the end-systolic volume
87
atrial fibrillation
insufficient cardiac output, ventricles not harmed. Electrical pathway to atria is not organized so depolarizing. Caused by damage to SA node or heart attack. AV node has taken over as pacemaker, no atrial contraction
88
Electrocardiogram
a record or display of a person's heartbeat produced by electrocardiography.
89
P wave
atrial depolarization (contraction) increase in ventricular pressure due to the pressure of the blood inside the ventricle
90
QRS complex
depolarization of the ventricles mitral and tricuspid valves close, causing opening in semilunar valves and aortic valve to have blood ejected
91
T wave
ventricular repolarization
92
What is happening from the time the mitral valve closes and the aortic valve opens? What causes the aortic valve to open?
Big contraction. Pressure is building in the left ventricle. The aortic valve opens as the left ventricle contracts and blood flows into the aorta
93
Diastole ends with
atrial contraction
94
Exercising muscles
```
increase size of muscle fiber (hypertrophy)
increase enzymes of energy metabolism
increase mitochondria (esp endurance)
increase myoglobin
increase capillary density
```
95
Microdamage theory
triggering gene expression according to a proteomet
96
blood flows
right atria, thru AV valve, to right ventricle, thru semilunar pulmonary valve, to pulmonary artery, to lungs to get oxygenated and release CO2, back thru pulmonary veins to left atria thru mitral valve (bicuspid valve), to left ventricle, thru aortic valve, thru aotra to organs
97
first heart sound
closing of mitral and tricuspid valves at the start of systole (contraction)
98
Second heart sound
closing of semilunar valves (aortic and pulmonary valves) marking the end of systole (contraction)
99
Amount of blood eject in a beat
~60-80% so alwys some blood left in ventricles
100
Cardiac output
stroke volume * heart rate
101
Regulation of Stroke volume
the amount of blood at the end of diastole, relaxation .Atria have spewed blood, causing a stretch to the filaments in each aorta, determines how much/how strong the stretch/contraction
102
How much blood there is depends on
contraction
103
How much blood there is depends on
contraction
104
What would happen if a blood clot blocks flow in the right lung?
Less oxygenated blood would be able to flow from right lung back to the heart, leading to a build up of blood in capillary bed, leading to pulmonary edema. Fluid buildup in the lung, increasing pressure causing right ventricle to have to pump harder to overcome pressure in the lung. Body responds by sympathetic
105
What's happening in capillary bed?
Blood comes out of aorta to capilalry beds, fluid spreads out in capillary bed, allowing movement of blood through fenestrated tissues except in blood brain barrier
106
Capillary/Tissue fluid exchange
Passive process, depending on pressure differences
107
What's happening in capillary bed?
Blood comes out of aorta to capilalry beds, fluid spreads out in capillary bed, allowing movement of blood through fenestrated tissues except in blood brain barrier
108
Capillary/Tissue fluid exchange
Passive process, depending on pressure differences. Blood plasma contains water, ions, nutrient molecules (glucose, amino acids, protein, lipids), and waste molecules. These substances can be transported from the blood capillaries to the interstitial fluid to the cells and back again by diffusion, filtration, osmosis, and active transport.
109
πp
colloid osmotic pressure of plasma
110
πi
colloid osmotic pressure of interstitial fluid
111
πi
colloid osmotic pressure of interstitial fluid
112
πi
colloid osmotic pressure of interstitial fluid
113
Frank-Starling Law
Regulates stroke volume because it says
1. increase in end diastolic volume increases contraction because filaments overlap so increasing stroke volume so contract
114
ADH
antidiuretic hormone from the kidney works to retain more water which will bring that water into the blood volume, urination decreases, stimulates thirst, restores blood volume.
115
When is ADH stimulated?
If increase salt intake because more fluid in the
116
The three main drugs used to treat essential hypertension are: diuretics, B-adrenergic receptor blockers (beta-blockers) and calcium channel blockers. Explain how they work
essential hypertension- high blood pressure with no known cause
diuretics- act as
117
diuretics
increase urine volume, thus decreasing blood volume and pressure , allowing you to get rid of unneeded water and salt though the urine. ad
118
ADH
stimulates smooth muscle vasoconstriction, increasing resistance, therefore pressure increaes
119
ADH effects on kidney
Makes kidneys reabsorb more water, by adding more water channels, Increase stroke volume and bp
120
ADH
Increases blood pressure
