Can some please give me the definition of systole and diastole?
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Cardiac cycle is the term used to describe the sequence of events that occur as a heart works to pump blood through the body. The frequency of the cardiac cycle is the heart rate.\n\nEvery single 'beat' of the heart involves three major stages: atrial systole, ventricular systole and complete cardiac diastole. The term systole is synonymous with contraction of a muscle. Electrical systole is the electrical activity that stimulates the myocardium of the chambers of the heart to make them contract. This is soon followed by Mechanical systole, which is the mechanical contraction of the heart.\n\nThe term diastole is synonymous with relaxation of a muscle.\n\nThroughout the cardiac cycle, the blood pressure increases and decreases.
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According to the site listed in sources:\n\n\nHow does a blood pressure gauge (sphygmomanometer) work? What exactly is blood pressure?\n &#92; \n     \nYour heart is an amazing pump. It works reliably for decades, and it safely pumps blood -- one of the trickiest liquids around. In the same way, your blood vessels are pipes. They take the output from the pump and distribute it throughout the body. A blood pressure gauge is simply a way to measure the performance of the pump and the pipes. \nThere are two numbers in a blood pressure reading: systolic and diastolic. For example, a typical reading might be 120/80. When the doctor puts the cuff around your arm and pumps it up, what he/she is doing is cutting off the blood flow with the pressure exerted by the cuff. As the pressure in the cuff is released, blood starts flowing again and the doctor can hear the flow in the stethoscope. The number at which blood starts flowing (120) is the measure of the maximum output pressure of the heart (systolic reading). The doctor continues releasing the pressure on the cuff and listens until there is no sound. That number (80) indicates the pressure in the system when the heart is relaxed (diastolic reading). \n\nIf the numbers are too high, it means that the heart is having to work too hard because of restrictions in the pipes. Certain hormones, like adrenaline (which is released when you are under stress) cause certain blood vessels to constrict, and this raises your blood pressure -- if you are under constant stress, your blood pressure goes up, and it means that your heart has to work too hard. Other things that can increase the blood pressure include deposits in the pipes and a loss of elasticity as the blood vessels age. \n\nHigh blood pressure can cause the heart to fail (from working too hard), or it can cause kidney failure (from too much pressure).
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look at this 3D pic then read\n\nhttp://library.thinkquest.org/C003758/rotate.htm\n\nIn the human body, the heart is normally situated slightly to the left of the middle of the thorax, underneath the sternum (breastbone). The heart is usually felt to be on the left side because the left heart (the left part of the heart) is stronger (it pumps the blood out). The heart is enclosed by a sac known as the pericardium and is surrounded by the lungs.Betwen the pericardium and the heart there is a serous fluid to reduce friction during heart contractions. The apex is the blunt point at the base of the heart. A stethoscope can be placed directly over the apex and count the beats. In normal adults, its mass is 250-350 g (8-11 oz), but extremely diseased hearts can be up to 1000 g (2 lb) in mass. It consists of four chambers, the two upper atria (singular: atrium ) and the two lower ventricles. On the right is a picture of a fresh human heart which was just removed from a 64 year old British gentleman. The mass for a thin white male is usually 270-300 grams (9-11 ounces) with little fat.\n\nA septum divides the right atrium and ventricle from the left atrium and ventricle, preventing blood from passing between them. Valves between the atria and ventricles (atrioventricular valves) maintain coordinated unidirectional flow of blood from the atria to the ventricles. The ventricular systole consists of the contraction of the ventricles and flow of blood into the circulatory system. Again, once all the blood empties from the ventricles, the pulmonary and aortic semilunar valves close. Finally complete cardiac diastole involves relaxation of the atria and ventricles in preparation for refilling with circulating blood.\n\nThe function of the right side of the heart (see right heart) is to collect deoxygenated blood from the body and pump it into the lungs (pulmonary circulation)so that carbon dioxide can be dropped off and oxygen picked up. This happens through a process called diffusion. The left side (see left heart) collects oxygenated blood from the lungs and pumps it out to the body (systemic circulation). On both sides, the lower ventricles are thicker than the upper atria.\nOxygen-depleted or deoxygenated blood from the body enters the right atrium through two great veins, the superior vena cava which drains the upper part of the body and the inferior vena cava that drains the lower part which drains the portal cyrculation too full with nutrients to nourish the body. The blood then passes through the tricuspid valve to the right ventricle. The right ventricle pumps the deoxygenated blood to the lungs, through the pulmonary artery. In the lungs gaseous exchange takes places and the blood releases carbon dioxide into the lung cavity and picks up oxygen which is called external respiration. The oxygenated blood then flows through pulmonary veins to the left atrium. From the left atrium this newly oxygenated blood passes through the mitral valve (also called the bicuspid valve) to enter the left ventricle. The left ventricle then pumps the blood through the aorta to the entire body. Even the lungs take some of the blood supply from the aorta via bronchial arteries.\n\nThe left ventricle is much more muscular, which is 1.3 - 1.5 cm (.5-.6 in) thick, than the right, 0.3 - 0.5 cm ( .1-.2 in) thick, as it has to pump blood around the entire body, which involves exerting a considerable force to overcome the vascular pressure. As the right ventricle needs to pump blood only to the lungs, it requires less muscle.\n\nEven though the ventricles lie below the atria, the two vessels through which the blood exits the heart (the pulmonary artery and the aorta) leave the heart at its top side.\n\nThe contractile nature of the heart is due to the presence of cardiac muscle in its wall which can work continuously without fatigue. The heart wall is made of three distinct layers. The first is the outer epicardium which is composed of a layer of flattened epi
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The sequence of events in the heart between the start of one contraction and the start of the next.
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AREA\n\nPressure (symbol: p) is the force per unit area acting on a surface in a direction perpendicular to that surface. Mathematically:    P=F/A\nwhere:\np is the pressure \nF is the normal force \nA is the area.
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The  heart.  I read about it in a book.  I forget the title.
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A sphygmomanometer (note spelling) works by completely cutting off the blood flow with high pressure, and then gradually decreasing that pressure until blood flows again.  The nurse determines this by listening with a stethoscope.  When she first hears blood begin to flow with a loud sound, that is the systolic blood pressure.  When the sound is no longer heard, that is the diastolic blood pressure.  So the cuff just reports how much pressure it is applying.  The nurse has to determine at what point the body responds.
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A pressure is defined to be a measurement of the amount of force acting on an object per unit area\n\nP = F / A   the S.I units for pressure are the N / m^2 which is also called a Pascal (Pa)
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Q1) True\nQ2) True\nQ3) True\nQ4) True\nQ5) True (so many cases)\nQ6) Heart pomps more than 3500 L/hour. This means 10 times more than the amount u said - false
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c) ventricular pressure falls below atrial pressure\n \nThe atrioventricular valves are the tricuspid and the mitral valves:\nThe tricuspid valve opens and the right ventricle fills with blood from the right atrium.\nThe mitral valve opens and the left ventricle fills with blood from the left atrium.\n\nSystole is when the heart muscle contracts diastole is when the heart muscle relaxes.
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The system of veins and arteries that moves (circulates) the blood around in your body.
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Blood pressure = Cardiac output * total peripheral resistance.\n\ncardiac output is the amount of blood pumped out by the left ventrical per minute~5L/min\n\nCardiac output= heart rate * stroke volume\n\nheart rate is number of times the heart beats per minute and stroke volume is End systolic volume - end diastolic volume. \n\nWhen your start to run, there will be a mass sympathetic discharge from your brain. So your hearts pumps harder and faster. Heart rate increases and heart contractility increases. so cardiac output increases from 5 L to say 8L or more. However BP does not increase as much because total peripheral resistance acturally decreases instead of incrases. As you run, the mucles that are oxygen starved release vasodilators into the blood vessels. These cause the smooth muscle around the arterioles to vasodilate. Therefore resistance to blood flow actually decreases. Hope this explains what you've been looking for.
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That blood pressure is perfectly safe.  The guidelines for blood pressure are systolic (top number) be below 140 and the diastolic (the bottom number) be below 90.  Of course everyone is different.  If you have had that reading for most of your life then that is a normal blood pressure for you.
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How much blood does your heart pump in one minute? This is called cardiac output. \n\nTo calculate cardiac output you need to know your body surface area in square meters and your cardiac index (how much blood is pumped per minute for every square meter of body surface area).
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overall system that's working with the heart. Cardio - heart, vascular- blood vessels.
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Pulmonary arteries\nPulmonary veins\nAorta (Arch)\nPericardial sac\nEpicardium\n\nThe contraction and relaxation of the heart chambers and the heart rate.
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Hypertension means high blood pressure. This generally means:\n\nSystolic blood pressure is consistently over 140 (systolic is the "top" number of your blood pressure measurement, which represents the pressure generated when the heart beats)\nDiastolic blood pressure is consistently over 90 (diastolic is the "bottom" number of your blood pressure measurement, which represents the pressure in the vessels when the heart is at rest)\nEither or both of these numbers may be too high.\n\nBlood pressure is determined by the amount of blood pumped by the heart, and the size and condition of the arteries. Many other factors can affect blood pressure, including volume of water in the body; salt content of the body; condition of the kidneys, nervous system, or blood vessels; and levels of various hormones in the body.\n\nEssential hypertension has no identifiable cause. It may be caused by genetics, environmental factors, or even diet, such as how much salt you use.\n\n"Secondary" hypertension is high blood pressure caused by another disorder. This may include:\n\nadrenal gland tumors\nCushing's syndrome\nkidney disorders\nglomerulonephritis (inflammation of kidneys)\nrenal vascular obstruction or narrowing\nrenal failure\nuse of medications, drugs, or other chemicals\noral contraceptives\nhemolytic-uremic syndrome\nHenoch-Schonlein purpura\nperiarteritis nodosa\nradiation enteritis\nretroperitoneal fibrosis\nWilms' tumor