Term
| meaning of the word cardiovascular |
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Definition
| Cardio- heart; vascular- blood vessels |
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Term
| some of the transport roles of blood |
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Definition
| -O2 and CO2 (together with the respiratory system)
-Nutritive functions – transport of the digested products
-Excretory substances – metabolic wastes (urea), water & ions |
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Term
| some of the regulatory roles of blood |
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Definition
-hormonal regulation
-temperature regulation |
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Term
| some of the protective roles of blood |
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Definition
-Leukocytes (WBC) and body defense
-Blood clotting mechanism |
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Term
| some things that can happen as a result of lack of oxygen |
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Definition
| -Interruption of blood to brain for 8 sec – unconsciousness
-Lack of O2 (cardiac arrest) for 6 min – brain death |
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Term
|
Definition
4 chambers
-2 atria
-2 ventricles
[image] |
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Term
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Definition
receive venous blood pump it into ventricles
[image] |
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Term
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Definition
receive atrial blood pump it into arterial systems
[image] |
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Term
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Definition
systemic circulation
[image] |
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Term
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Definition
pulmonary circulation
[image] |
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Term
| The cardiac cycle (contraction & relaxation) |
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Definition
-When pumps contract (systole) – ejection of blood to arteries
-When pumps relax (diastole) – filling of blood
-Intermittent (on & off) pattern of blood flow in the heart – during relaxation (filling), no blood flow to blood vessels |
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Term
| diagram of the pulmonary and systemic circulation of the circulatory system |
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Definition
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Term
| the pathway for systemic circulation |
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Definition
| left atrium (oxygenated blood, high PO2) --> ventricle --> aorta --> arteries --> arterioles --> peripheral capillaries --> (deoxy blood, low PO2) --> … --> veins --> vena cava --> right atrium |
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Term
| the pathway for pulmonary circulation |
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Definition
| right atrium (deoxy blood) --> ventricle --> pul artery --> pul arterioles --> pul capillaries for gas exchange (oxygenated blood) --> … --> pul vein --> left atrium |
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Term
| how the pulmonary and systemic circulations relate to each other |
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Definition
Pulmonary + systemic circulations = one close-type circulatory system --> flow rate through systemic circulation = flow rate through pulmonary circulation
[image][image] |
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Term
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Definition
| the part of the circulatory system that does gas exchange in the lungs |
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Term
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Definition
| the part of the circulatory system that delivers oxygen to the peripheral tissue |
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Term
| why the rates of pulmonary and systemic circulation have to be equal to each other |
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Definition
| because if they're not, there will be congestion of blood in either the lungs or the systemic circulation |
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Term
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Definition
-left pump: left atrium and left ventricle
-right pump: right atrium and right ventricle
[image] |
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Term
|
Definition
-aorta
-arteries
-arterioles
-capillaries
-venules
-veins
-vena cava
[image] |
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Term
| some components of the lymphatic system |
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Definition
-lymphatic vessels
-lymph nodes |
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Term
| the function of cardiac valves |
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Definition
| they allow the circulation one-directional |
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Term
| Atrioventricular (AV) valves a.k.a. bicuspid (left) & tricuspid (right) valves |
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Definition
Allow blood to flow from atria to ventricles
[image] |
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Term
| Semilunar valves a.k.a. aortic (left) & pulmonic (right) valves |
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Definition
Allow blood leave ventricles --> pulmonary or systemic circulation
[image] |
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Term
| some details about the flow of blood |
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Definition
-based on pressure gradient
-blood flow from high pressure to low pressure
-relaxation sucks blood in
-cardiac contraction pushes blood out |
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Term
| basic structure of arteries and veins |
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Definition
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Term
| the layers of blood vessels |
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Definition
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Term
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Definition
endothelial cell layer present in all vessels (arteries, veins, capillaries)
-separates the lumen of the blood vessel from the rest of the structures in the blood vessel
[image] |
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Term
| how the composition of arteries differs from that of veins |
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Definition
| arteries contain more smooth muscle and elastin than veins |
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Term
| compliance aka distensibility aka expansibility |
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Definition
how well this blood vessel can be expanded
[image] |
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Term
| Elasticity aka contractility |
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Definition
how well this blood vessel can bounce back to its original shape, original diameter, after expansion
[image] |
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Term
| the role of smooth muscle and elastin in arteries |
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Definition
| reduce the magnitude of bp fluctuation in the arteries |
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Term
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Definition
they prevent black flow, ensure uni-directional flow
-they need valves because they don't have as much smooth muscle as arteries do |
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Term
| type of blood vessel with no smooth muscle |
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Definition
| capillaries; they only have endothelium |
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Term
| function of skeletal muscle pump |
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Definition
-Rhythmic contraction & relaxation of skeletal muscles surrounding the veins --> ↑ blood return to right atrium
-“Second heart” of the body
[image] |
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Term
| Compliance/elasticity is mainly due to... |
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Definition
| elastic fibers (rubber bands) |
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Term
| the process of compliance (expansibility, distensibility) |
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Definition
↑ in BP during systole (ventricles are larger than aorta) --> ↑ lumen diameters --> BP? --> limits the magnitude of BP rise
[image] |
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Term
| the process of elasticity (contractility) |
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Definition
↓ in BP during diastole --> ↑ arterial elasticity (tendency to recoil to previous shape after deformation) --> sustains BP from dropping too low --> allows continuous blood perfusion to tissues
[image] |
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Term
| the distribution of blood in veins and arteries |
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Definition
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Term
| some functions of the lymphatic system |
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Definition
-Transports interstitial fluid (lymph)
-Transports absorbed fat from small intestine to blood
-Lymph nodes and lymphocytes –immune functions |
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Term
| the flow between the lymphatic system and the cardiovascular system |
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Definition
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Term
| structure of lymphatic vessels |
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Definition
Closed-ended lymphatic capillaries in systemic and pulmonary circulations
[image] |
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Term
| the path lymph takes in the lymphatic system to the circulatory system |
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Definition
| Lymphatic capillaries --> lymph ducts --> thoracic duct (lt.) and right lymphatic duct --> subclavian veins --> vena cava --> rt. atrium |
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Term
| how blood is separated into its components |
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Definition
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Term
| the components of blood and their percentages |
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Definition
-plasma: 55%
-buffy coat (leukocytes and platelets): <1%
-erythrocytes: 45% |
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Term
| dome substances found in blood plasma |
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Definition
| -Dissolved ions – Na+ (major) and others
-Plasma proteins (7-9% of plasma, gm/dl) --> colloid osmotic P
+Albumins
+Globulins |
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Term
|
Definition
-~60%-80% of plasma proteins
-produced by the liver
-for osmotic P and buffering blood pH |
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Term
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Definition
-alpha & beta globulins
-produced by liver
-transport of lipids & fat-soluble vitamins
-gamma globulins (immunoglobulins) |
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Term
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Definition
| the force that the fluid needs to overcome before fluid can go out of capillary pores, into the interstitial tissue |
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Term
| why the blood plasma needs plasma proteins |
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Definition
| to create colloid osmotic pressure to prevent the fluid from going out of capillary pores, into the interstitial tissue |
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Term
| the cause and effect of blood plasma concentration being too low in the blood plasma |
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Definition
-caused by liver problem
-edema results |
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Term
| composition of buffy coat component of blood |
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Definition
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Term
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Definition
flattened biconcave discs to increase surface area for the diffusion of oxygen
-No nuclei, no mitochondria
-Hemoglobin (Hb) – O2 & CO2 |
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Term
| the number of RBC (erythrocytes) produced each day |
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Definition
| Produce 300 x 109 RBCs each day |
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Term
| RBC (erythrocyte) levels in men and women and why it's different |
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Definition
| ♂ – 5.1-5.8; ♀ – 4.3-5.2 (106/mm3)
-the difference is because testosterone stimulates production of erythropoietin, which stimulates RBC production |
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Term
| the types of formed elements that can be found in blood |
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Definition
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Term
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Definition
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Term
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Definition
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Term
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Definition
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Term
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Definition
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Term
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Definition
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Term
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Definition
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Term
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Definition
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Term
| why erythrocytes (RBCs) are biconcave discs |
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Definition
| to increase surface area for the diffusion of oxygen |
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Term
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Definition
| white blood cells that have granules in the cytoplasm, such as basophils (fewest), eosinophils, and neutrophils aka polymorphonuclear cells (PMN) (50-70% WBC) |
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Term
| the types of granulocytes |
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Definition
-basophils (fewest)
-eosinophils
-neutrophils aka polymorphonuclear cells (PMN) (50-70% WBC) |
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Term
| why neutrophils are also called polymorphonuclear cells (PMN) |
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Definition
| because their nucleus divides into multiple leaflets; the older the neutrophil, the more leaflets |
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Term
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Definition
| white blood cells that do not contain granules in their cytoplasm, such as monocytes & lymphocytes (adaptive immunity) |
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Term
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Definition
| fragments of megakaryocytes |
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Term
| how Thrombocytes (platelets) are formed |
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Definition
liver and kidneys
produce thrombopoietin, which stimulates bone marrow to produce megakaryocytes, which then fragment into smaller pieces |
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Term
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Definition
formation of blood cells
-Erythropoiesis (production of RBC)
-Leukopoiesis (production of WBC)
-Thrombopoiesis (production of thrombocytes) |
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Term
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Definition
| production of RBC
-Stimulated by erythropoietin from kidney (low PO2)
-Site of production – bone marrow
-RBC life span – 120 days |
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Term
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Definition
| production of WBC
-Controlled by inflammatory cytokines
-Site of production – lymphoid tissues, such as the thymus, the lymph nodes, and spleen
-WBC conc. ~ 5-9x103/mm3
-life span – 100-300 days (agranular WBC, such as monocytes and lymphocytes), <3 days (granular WBC, such as neutrophils) |
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Term
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Definition
production of thrombocytes
-Thrombopoietin – produced by liver and kidneys
-Action site – bone marrow; life span - 5-9 days |
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Term
| what happens to old red blood cells after 120 days? |
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Definition
they get degraded by lymphoid tissue, plus the liver, and become bilirubin
-after being oxidized, part of that bilirubin becomes part of the feces and part of it becomes the color of the urine |
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Term
| the white blood cell that is the first line of defense |
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Definition
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Term
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Definition
| physically separates blood from collagen and other platelet activators
-secrete nitric oxide (NO) and prostacyclin (PGI2) for ↑ Vasodilation and ↓ platelet aggregation |
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Term
| how endothelial cells prevent blood clotting in intact vessels |
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Definition
| -they secrete nitric oxide (NO) and prostacyclin (PGI2) for ↑ Vasodilation and ↓ platelet aggregation
-Endothelial membrane contains CD39 to:
Convert blood ADP --> AMP + Pi, thus ↓ ADP --> ↓ platelet plug formation
[image] |
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Term
| what happens when the blood vessel is damaged? |
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Definition
| injury --> von Willebrand factor (VWF) from injured endothelial cells binds to collagen and platelets --> platelets adhere to subendothelial collagen --> Activated platelets release ADP and thromboxane (TxA2) --> Thromboxane & serotonin cause vasoconstriction --> ADP & thromboxane attract other platelets --> forms the platelet plug
[image] |
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Term
| how aspirin reduces blood clotting |
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Definition
| Aspirin --> ↓ formation of thromboxane --> ↓ formation of platelet plug |
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Term
| depiction of the intrinsic and extrinsic pathways of blood clotting |
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Definition
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Term
| Intrinsic pathway of blood clotting |
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Definition
activated by collagen of damaged b.v. (within)
[image] |
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Term
| Extrinsic pathway of blood clotting |
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Definition
activated by tissue thromboplastin (tissue factor) from the surrounding damaged tissue (outside b.v.)
[image] |
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Term
| Intrinsic and extrinsic pathways of blood clotting working together |
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Definition
--> common pathway (factor X)
-Factor X activates prothrombin --> thrombin
-Thrombin activates fibrinogen (soluble) into fibrin (insoluble) |
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Term
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Definition
| platelet plug + fibrin meshwork + RBC |
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Term
| The clotting sequence requires... |
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Definition
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Term
| what happens to plasma after clot formation? |
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Definition
plasma --> serum
-plasma = serum + fibrinogen |
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Term
| the clot dissolution process |
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Definition
1: Plasminogen – produced by liver, inactive, in blood
2: Tissue plasminogen activator (tPA) from endothelial cells converts plasminogen → plasmin (bioactive)
3: Plasmin cleaves fibrin into split products → clot removed |
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Term
| how anticoagulants reduce blood clotting |
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Definition
| Endogenous heparin → ↑ plasma antithrombin III → ↓ clot formation |
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Term
| some examples of anticoagulants |
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Definition
| Sodium citrate & EDTA – chelate Ca2+
NOTE: they can only be used in vica levels in bloodtro, because you dont want to deplete |
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Term
| Function of vitamin K in clotting |
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Definition
| -Vit K convert glutamate into gamma-CO-glutamate in some clotting factors (II, VII, IX & X) → functional clotting factors
-gamma-CO-glutamate attracts Ca2+ to clotting factors |
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Term
| how Coumarin inhibits blood clotting |
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Definition
-inhibits vit K activities (slow)
-Warfarin as a rodenticide, clinically used as a blood thinner |
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Term
| how heparin is an anticoagulant |
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Definition
| Endogenous heparin → ↑ plasma antithrombin III → ↓ clot formation |
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Term
| something bad blood thinners can do to the brain |
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Definition
| sometimes cause microembolism in brain |
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Term
| the 2 major parts of the cardiac cycle |
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Definition
-Systole – contraction phase, for ejection
-Diastole – relaxation phase, for filling into ventricle |
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Term
| diagram of the sequence of the cardiac cycle for a cycle of 0.8 seconds (75 cycles per minute) |
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Definition
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Term
| the timing of the contraction of the atria and the ventricles and why |
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Definition
-Atria contract simultaneously; ventricles follow 0.1-0.2 seconds (second) later
-Atria contract first due to the location of pacemaker
-both atria have the same myocardium and both ventricles have the same myocardium |
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Term
| The end-diastolic volume (EDV) |
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Definition
-Also known as preload
-80% EDV is due to ventricular relaxation
-The final 20% EDV is due to atrial contraction |
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Term
| The end-systolic volume (ESV) |
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Definition
-Also known as afterload
-Ejection fraction – systole ejects about 2/3 (55-70%) of its blood vol, leaving about 1/3 as ESV |
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Term
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Definition
| the amount of blood ejected from ventricles during systole |
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Term
| the sequence of the cardiac cycle |
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Definition
1: atrial contraction during the final phase of ventricular relaxation
-conduction delay from atria --> ventricles = 0.1-0.2 seconds
2: atrial contraction --> ventricular contraction (systole)
3: atria relax during ventricular relaxation (systole)
4: ventricular relaxation during the 2nd half of atrial relaxation
5: atria contract in the last 0.1 second of (ventricular) diastole |
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Term
| depiction of how blood moves through the heart |
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Definition
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Term
| During diastole, the intra-ventricular pressure can be ______, whereas the systemic arterial pressure is... |
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Definition
as low as 0 mm Hg
~80 mm Hg
this is because of the smooth muscles tone in the vessels |
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Term
| chart of the systolic and diastolic phase of the cardiac cycle |
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Definition
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Term
| the systolic ventricular part of the cardiac cycle (ventricular relaxation) |
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Definition
-Isovolumetric contraction (#1) – ventricles contract → ↑ ventricular BP; when > atrial BP → close AV valves; arterial BP still > ventricular BP → semilunar valves remain closed → no ejection of blood (iso-volume)
-Phase of ejection (#2) – when ventricular BP > arterial BP → open semilunar valves → blood ejects to arteries until ventricular BP < arterial BP → semilunar valves close → diastole
[image] |
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Term
| Isovolumetric contraction |
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Definition
| ventricles contract → ↑ ventricular BP; when > atrial BP → close AV valves; arterial BP still > ventricular BP → semilunar valves remain closed → no ejection of blood (iso-volume) |
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Term
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Definition
| when ventricular BP > arterial BP → open semilunar valves → blood ejects to arteries until ventricular BP < arterial BP → semilunar valves close → diastole |
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Term
| the diastolic ventricular part of the cardiac cycle (ventricular relaxation) |
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Definition
-Isovolumetric relaxation (#3) – ↓ ventricular BP ventricular BP
-Phase of rapid filling (#4) – when atrial BP > ventricular BP → AV valves open → rapid filling
-Phase of the final filling (#5) – caused by atrial contraction (beginning of the next cardiac cycle)
[image] |
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Term
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Definition
| ↓ ventricular BP ventricular BP |
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Term
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Definition
| when atrial BP > ventricular BP → AV valves open → rapid filling |
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Term
| Phase of the final filling |
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Definition
| caused by atrial contraction (beginning of the next cardiac cycle) |
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Term
| the sequence leading to the 1st "lub" sound of the heartbeat |
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Definition
caused by closure of AV valves
At the beginning of systole, when ventricular BP exceeds atrial BP --> AV valves closure --> turbulent blood flow --> produces the first heart sound, or "lub" at beginning of systole |
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Term
| the sequence leading to the 2nd "dub" sound of the heartbeat |
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Definition
caused by closure of semilunar valves
At the end of systole (near the beginning of diastole), when arterial BP exceeds ventricular BP intra-atrial P --> semilunar valves closure --> turbulent blood flow --> produces the second heart sound, or "dub" |
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Term
| the sequence that leads to the 3rd heart sound |
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Definition
caused by turbulence
occurs just after S2 when AV valve open --> rapid passive filling of ventricles --> turbulent blood flow --> S3 |
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Term
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Definition
abnormal heart sounds produced by turbulent blood flow
-caused by valvular defects |
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Term
| how valvular insufficiency/incompetent valves lead to heart murmurs |
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Definition
a valve that does not close adequately --> retrograde flow
-Damage to papillary muscles
Valves do not close properly. Murmurs produced as blood regurgitates through valve flaps |
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Term
| how valvular stenosis leads to heart murmurs |
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Definition
a valve which does not open adequately (thickened or calcified) --> restricts flow
-Impairs blood flow from left atrium to left ventricle
-Accumulation of blood in left atrium may cause pulmonary hypertension |
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Term
| how infection can lead to heart murmurs |
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Definition
| Infection (rheumatic endocarditis) leads to valvular stenosis, which causes heart murmurs |
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Term
| Septal defects in the heart |
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Definition
-usually congenital
-Holes in septum between the left and right sides of the heart
May occur either in interatrial (ASD) or interventricular septum (VSD)
Blood passes from left to right
-can cause heart murmurs
[image] |
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Term
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Definition
desmosome (physical connection) + connexon (gap junction for ionic conductance)
this is between all adjacent heart cells |
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Term
| where the intercalated disc is located between adjacent heart cells |
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Definition
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Term
| how the action potential spreads through myocardial (heart) cells |
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Definition
| Action potentials spread through myocardial cells through intercalated discs (gap junctions) --> Cardiac muscle functions as syncytium (atria vs. ventricles) |
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Term
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Definition
| resting membrane potential |
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Term
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Definition
| -pacemaker, spontaneous depolarization --> automaticity
-Caused by Na+ inflow through hyperpolarization-activated cyclic nucleotide-gated (HCN) channels that opens when hyperpolarized, open faster with cAMP stimulation |
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Term
| how the pacemaker action potential works |
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Definition
| -Depolarization – (main) voltage-gated Ca2+ channels --> Ca2+ inflow; (secondary) voltage-gated Na+ channels
-Repolarization – VG K+ channels open --> K+ diffuses outward
[image] |
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Term
| Resting membrane potential of contractile cells |
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Definition
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Term
| sequence by which an action potential causes a heartbeat |
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Definition
| AP at SA node (auto-rhythmic cells) --> AP at contractile cells --> voltage-gated fast Na+ channels open --> Na+ inflow --> rapid depolarization |
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Term
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Definition
| -Rapid reversal in membrane polarity to –15 mV
-Voltage-gated slow Ca2+ channels open --> Ca2+ inflow --> Ca2+ --> release from sarcoplasmic reticulum (SR) through Ca2+ stimulated Ca2+ release channels
-lasts ~100 ms in atria; ~300 ms in ventricles
-the Ca getting into the cells maintains the plateau phase, causing the action potential to last longer
[image] |
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Term
| changes in action potential, heart vs. neuron |
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Definition
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Term
| the path of the action potential from the SA node to causing the atria to contract |
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Definition
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Term
| the path the action potential takes from atria to ventricles |
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Definition
| atria --> AV node (slow conducting) --> Bundle of His --> Purkinje fibers --> all ventricular muscle cells --> Ca2+ inflow --> Ca2+ ↑ release from sarcoplasmic reticulum --> contraction of both ventricles simultaneously
the contraction of the ventricle is caused by excitation-contraction coupling |
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Term
| chart showing the action potential compared to the contraction |
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Definition
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Term
| the path the action potential takes from sinoatrial (SA) node to the atria and then the ventricles |
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Definition
| SA node --> atria --> AV node (slow conducting) --> Bundle of His --> Purkinje fibers --> all ventricular muscle cells --> Excitation-contraction coupling
Ca2+ inflow --> Ca2+ ↑ release from sarcoplasmic reticulum --> contraction of both ventricles simultaneously |
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Term
| why summation (tetanus) soes not occur in the heart |
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Definition
Refractory Periods
-Refractory periods ~ contraction time ~ 300 msec in ventricles
-Summation cannot occur |
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Term
| electrocardiogram (ECG or EKG) |
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Definition
| records the electrical activity of the heart by picking up the movement of ions in body tissues in response to this activity |
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Term
| how the ECG/EKG measures the electrical activity outside the heart |
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Definition
Electrodes connect to outside of the heart muscle
-Heart is bathed in the interstitial fluid with electrolytes --> conductive to electric flow
[image] |
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Term
| what the ECG/EKG does NOT do |
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Definition
-does NOT record the movement of ions of individual cells (the electrodes don't insert into the inside of the cells)
-does NOT record action potentials, but results from waves of depolarization
-does NOT record contraction or relaxation, but the electrical events leading to contraction and relaxation |
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Term
| depiction of the stages of the heartbeat and the ECG/EKG reading |
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Definition
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Term
|
Definition
caused by depolarization of the atria, when the entire mass of atria is depolarized, ECG returns to baseline
[image] |
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Term
|
Definition
caused by depolarization of the ventricles; during this time atria repolarize, but the event is hidden by the greater depolarization in ventricles
[image] |
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Term
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Definition
produced by repolarization of the ventricles
[image] |
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Term
| the electrical path for the 1st heart sound |
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Definition
| QRS wave --> systole (ventricular contraction) --> rise of intraventricular P --> AV valves close (1st heart sound) --> S1 |
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Term
| the electrical path for the 2nd heart sound |
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Definition
| T wave --> ventricular repolarization --> intraventricular P lower than arterial P --> semilunar valves close (2nd heart sound) --> S2 |
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Term
| the electrical path for the S-T segment |
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Definition
| AP transmission in ventricle --> plateau phase --> systole |
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Term
| how defective heart valves can lead to heart murmurs |
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Definition
| congenital defects or infection (rheumatic endocarditis) --> valves damaged |
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Term
| how mitral stenosis can lead to heart murmurs |
|
Definition
mitral valve becomes thickened and calcified
-narrows mitral valve such that it impairs blood flow from left atrium to right ventricle
-accumulation of blood in left atrium may cause pulmonary HTN (hypertension?) |
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Term
| LDL (low density lipoprotein) |
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Definition
| delivers cholesterol from liver to peripheral tissues, including blood vessel walls |
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Term
| HDL (high density lipoprotein) |
|
Definition
| delivers cholesterol from peripheral tissues to liver --> bile --> gut --> feces (eliminates excessive cholesterol from the body) |
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Term
| process by which atherosclerosis forms |
|
Definition
arteroial endothelial cells contain LDL R --> LDL-LDL R --> endocytosis --> oxidized LDL --> ... --> formation of atheroma (localized plaques of fat) --> atherosclerosis --> atherosclerosis --> reduce blood flow --> ↑ clot formation
[image] |
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Term
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Definition
| localized plaques of fat that protrude into the lumen of the arteries --> reduce blood flow --> ↑ clot formation |
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Term
| some nutrients that seem to reduce the risk of atherosclerosis |
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Definition
vit C, E, beta-carotene
-they reduce oxidation of LDL |
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Term
| meaning of the word atherosclerosis |
|
Definition
| sclerosis (hardening) of the artery due to atheromas |
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Term
| why the flow rate in pulmonary and systemic circulation has to be the same |
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Definition
| so that there's a smooth flow of blood through the big loop (analogous to traffic and traffic jams) |
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Term
| some structural components of the blood vessels |
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Definition
-Vascular lumen – hollow portion, allows blood flow
-Tunica interna (intima) – endothelium & elastic layer
-Tunica media – smooth muscle (more in arteries than in veins)
+this means veins have larger lumens
-Tunica externa (adventitia) – prevent overstretching
-Elastic fibers (elastins) are present in all 3 layers (interna, media & externa) of arteries, mainly in aorta & large arteries
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Term
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Definition
| Blood pressure (BP) = Force/Area |
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Term
| depiction of how the pressure gradient enables blood flow |
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Definition
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Term
| why the pressure for systemic circulation is higher than that for the pulmonary circulation |
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Definition
-because the syatemic circulation has to pump blood to the brain and the feet
-also, the level of the lung is very close to that of the heart, so doesn't need as high a blood pressure |
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Term
| the difference in blood pressure between the various parts of the circulatory system |
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Definition
Ventricular contraction generates ΔP → > arterial BP > capillary BP > venular BP > atrial BP
[image] |
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Term
| what happens if the compliance of a blood vessel = 0? |
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Definition
| can lead to hypertension or breaking of blood vessel or hemorrhage of weak blood vessel, such as stroke |
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Term
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Definition
| -Connect arterioles & venules
-Gas exchange (O2 & CO2)
-Fluid exchange (blood plasma <--> interstitial fluid)
-The exchange of nutrients, hormones, metabolic wastes etc.
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Term
| composition of capillaries |
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Definition
Smallest blood vessel
-Consist of endothelial cells (endothelium) & basement membrane
-Pores on endothelium
-Do NOT contain smooth muscle
[image]
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Term
| how the structure of veins and venules differs from that of arteries |
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Definition
-Thinner walls than arteries
-less smooth muscle
-larger lumen
-contain valves
[image] |
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Term
| Key functions of veins and venules |
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Definition
-adjust venous return of blood to right atrium
-valves inside veins at low BP (~6 mmHg), prevent black flow, ensuring uni-directional flow |
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