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33 Cards in this Set
- Front
- Back
what are the functions of blood? |
- transport needs; oxygen, nutrients, enzymes, hormones etc - transport waster; CO2 - regulate the body temperature - control of the osmolarity - maintain the composition of the extracellular fluid - control the distribution of hormones (endocrine system) - defense against infection (by white cells and immunoglobulins) |
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what is the circulation through the lungs called? via which side of the heart |
pulmonary circulation via right side of the heart |
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what is the circulation through the rest of the body called? via which side of the heart? |
the systemic circulation via left side of the heart |
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name the vessels of the circulation system |
Artery, arteriole, capillaries, venule, vein (O2 rich) (CO2 rich) |
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what are the physical differences between artery, capillary, and vein? |
artery- thicker muscles, resistance vessels capillary- one cell thick (endothelium) for rapid exchange vessels vein- thin walls, more distensible, storage or capacitance vessels with valves (most of the blood in the systemic circulation is located in the venous side of the circulation) |
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what is the name of the artery that connecting from the left ventricle to the body? |
aorta |
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what is the name of the vein that connecting to the right atrium? |
From the brain; superior vena cava from the body; interior vena cava |
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what is the name of the wall that divides the heart? |
intraventricular septum |
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what is the name of the artery that connecting from the right ventricle? |
pulmonary artery |
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what is the name of the vein connecting to the left atrium? |
pulmonary vein |
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what is the role of the valves in the vein? |
valves stop blood from flowing backwards. veins are often located in between the skeletal muscles and the muscle contraction compresses the veins as pump |
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what happen to the veins caused by poorly functioning valves? |
varicose veins; 静脈瘤 often found in legs valves are not closed properly, the blood can flow backwards |
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what is the simple equation that explains blood flow rate? |
Q= △P/ R Q= blood flow rate through any partof the circulation △P= perfusion pressure; differences between the arterial and venous pressure R= vascular resistance |
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what is the equation that explains the vascular resistance? |
R =8ηL/πr^4
The vascular resistance to blood flow within asingle blood vessel is essentially proportional tothe blood viscosity (η), the length of the vessel(L), and (inversely) to the vessel radius (r) tothe 4th power. In this way, small changes invessel diameter (=2r) (vasoconstriction,vasodilation) can produce large changes inresistance to flow |
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what is poiseuille's equation? |
Q = ΔPπr^4/ 8ηL describing idealised laminar flow of so-calledNewtonian fluids in long cylindrical straighttubes |
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what equation explains the velocity of the vascular blood flow? |
V=Q/A
V= velocity (cm/s) Q= blood blow (ml/s) A= total cross sectional area (cm^2) eg. capillaries has A=4500cm^2 and slow velocity V= 0.03 cm/s
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what is lymphatic system? |
The lymphatic system is part of the circulatory system and a vital part of the immune system, comprising a network of lymphatic vessels that carry a clear fluid called lymph directionally towards the heart.
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how much volume of fluid transported through the lymphatic per day? |
total plasma volume in the circulation |
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how much proteins returned by the lymphatics to the blood perday? |
between a quarter to one half of the circulating plasma proteins
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what is lymphatic system essentially composed of? |
closed-end lymphatic vessels, nodes,and lymphoid tissue.
lymph fluid only flows one direction lymph is filtered at the lymph nodes to remove foreign particles such as bacteria |
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How does left ventricular heart failure lead to oedema? |
The hydrostatic pressure in pulmonary capillaries build up high. therefore excessive plasma filtration > reabsorption via lymphatic system this situation may then lead to pulmonary oedema, a condition that can seriously interfere with gas exchange in the lungs |
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how does pregnancy and right heart failure lead to oedema? |
during pregnancy or in right heart failure, the elevation of venous pressure in the legswith prolonged standing, is transmitted back to the capillaries, and can again lead toenhanced capillary filtration which exceeds the capacity of the lymphatic system, causingoedema of the lower extremities and abdomen. (called pitting oedema)
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what does extremities mean? |
四肢
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what is starling equation? |
Qf = k[(Pc +πi )] - (Pi +πp)]
Qf= rate of fluid movement Pc= capillary hydrostatic pressure Pi= interstitial fluid hydrostatic pressure πp= plasma osmotic pressure (exerted by plasma proteins) πi= interstitial fluid osmotic pressure (exerted by smallamounts of albumin escaping from capillaries) k = filtration constant for capillary membrane |
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what is cardiac arrhythmia? |
the orderly sequence of cardiaccontractions becomes seriously disrupted either by ischaemic heart disease or other(hormonal?) factors, the therapeutic use of drugs (or even implanting an artificialpacemaker) may be necessary to restore normal rhythm.
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what is angina pectoris? |
the most common symptom associated with ischaemic (coronary)heart disease, manifested as a gripping or crushing central chest pain (or discomfort)that may radiate to one or both arms and the neck.
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how does angina cause pain? |
The pain arises due tomyocardial hypoxia, as a result of inadequate coronary blood flow; the latter mayresult from a partial occlusion of the coronary vessels by atheromatous (fatty) depositsor coronary artery spasm, again in association with atheromatous disease
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what is heart failure ? |
the basic problem in heart failure is ventricular dysfunction, with theresult that the heart cannot pump enough blood around the circulation to meet themetabolic demands of various body organs during exercise, (and ultimately also atrest).
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what are the causes of heart failure? |
It may be caused by disease of the heart muscle itself, or circulatory factors(valvular incompetence, hypertension).
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what is myocardial infarction? |
heart attack - usually due to a sudden coronary thrombosis in asegment of the myocardium, in patients with coronary atheroma. |
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what is coronary atheroma? cause? what does it consist of? |
coronary artery narrowed by atherosclerotic plaque initially due to the damaged endothelium and macrophages transformed into foam cells the atherosclerotic plaque consists of lipids, calcium and cellular debris |
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what is stroke? what might be the causes? |
a stroke occurs when the brain's blood supply is cut off
several reasons:- (1) atheromatous occlusion of arteries in the brain (2) a blood clot(thrombus) may form in the atheromatous vessel, leading to closing off of the artery(cerebral thrombosis). A travelling blood clot (embolus) can also block a small artery in the brain (3) a weak spot in a cerebral blood vessel may cause a rupture - cerebralheamorrhage, or bulging of the weak spot may cause a cerebral aneurism (4) rarely,a brain tumour could press on blood vessels and shut off their blood supply |
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what is rapture? |
血管の破裂
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