Structure And Function Of The Heart Physical Education Essay

Structure And Function Of The Heart Physical Education try onThe cardiovascular arrangement is a very thickening and unique agreement. The principal(prenominal) structures of the cardiovascular scheme include the summation, farm animal, and agate line vass arteries, capillaries and venas. It is a system that entirelyows any nutrients such as aminic acids, electrolytes and lymph, b either upes, hormones, and argumentation cells to pass end-to-end the system, these all aid in the process of fighting diseases, stabilizing body temperature and primary(prenominal)taining homeostasis.Coronary, pulmonic and general circulations argon the systems that go out bank line to be pump by dint of and throughout the body, coronary circulation is the system that allows squanderer to be pumped through the kernel, pulmonary circulation is the system that pumps note through to the lungs and the systemic circulation which is the system that pumps the blood swell-nigh the rest of the body and to the remaining organs. As humans we have a closed cardiovascular system which means the blood never bequeaths the circulation of the blood vessels. The coronary circulation is part of the systemic circulation by definition it supplies blood to muscles- muscles of the meat (myocardium), moreover it is the only system to provide the summation with blood. The blood comes from the aorta and filters through into the by rights atrium. If the middle didnt receive the blood supply, it would cause severe thread damage.The pulmonary circulation uses the pulmonary artery to take de-oxygenated blood away from the heart through to the lungs which is where the blood is hence oxygenated. The de-oxygenated blood enters the right atrium of the heart and flows through the tricuspid valve and then from there it flows into the right ventricle, here it is then pumped through the pulmonary semilunar valve into the pulmonary artery to the lungs. In the lungs is where the gas ex change takes place, where the CO2 is released and the blood then absorbs oxygen. This is the stage when the pulmonary vein returns the freshly oxygenated blood to the heart.The systemic circulation on the other hand takes the oxygenated blood from the heart and violates it throughout the rest of the body except from the lungs. The system then provides all other organs with the oxygenated blood, the circulation then returns all of the de-oxygenated blood vertebral column to the heart for the process to start all over again. The systemic circulation is a very much lengthier system than the pulmonary circulation due to transporting blood all over the body.(1)The heart pumps oxygenated blood to the body and deoxygenated blood to the lungs. In the human heart there is one atrium and one ventricle for each circulation, and with both a systemic and a pulmonary circulation there ar four house in total left atrium, left ventricle, right atrium and right ventricle. The right atrium is the upper chamber of the right side of the heart. The blood that is returned to the right atrium is deoxygenated (poor in oxygen) and passed into the right ventricle to be pumped through the pulmonary artery to the lungs for re-oxygenation and removal of carbon dioxide. The left atrium receives newly oxygenated blood from the lungs as well as the pulmonary vein which is passed into the strong left ventricle to be pumped through the aorta to the different organs of the body.The blood circuit is flows in the shape of a figure of 8. There are two loopings to this circuit. The make loop carries the blood from the heart to the lungs and back (the pulmonary circulation). The bottom loop carries the blood from the heart all over the body (systemic circulation).The 4 main stages of the cardiac cycle areAtrial Diastole -which is where the snuff it chamber (atria) relaxes and fills with blood from the veinsAtrial Systole- where the atria contracts and blood is furiousness into the rel axing bottom chambers which are otherwise known as ventriclesVentricular systole- which is where the ventricles contract and blood is forced out of the heart in to the arteries.Ventricular diastole -when the ventricles relax and become coiffe for the next pump cycle.The circulatory system also consists of the lymphatic system this is a non-closed system that carries a clear liquid called lymph towards the heart and allows an add up of 20 litres of blood per day through capillary filtration which removes plasma plot of land leaving the erythrocytes. Around 17 litres of filtered plasma get reabsorbed into the blood vessels however 3 litres are then left behind in the interstitial fluid. The main role of the lymph system is to provide an auxiliary route for the unnecessary 3 litres to return to the blood. (4) The lymphatic system has multiple interrelated run shortsit is answerable for the removal of interstitial fluid from tissuesit absorbs and transports fatty acids and fats as chyle from the digestive systemit transports white blood cells to and from the lymph nodes into the bonesThe lymph transports antigen-presenting cells (APCs), such as dendritic cells, to the lymph nodes where an resistive response is stimulated.There are three main blood vessels in the cardiovascular system, these are the arteries, veins and capillaries arteries are amenable for carrying the blood away from the heart, they are made up of a thick elastic muscular environ, which is qualified of stretching as blood is being pumped through at a advanced pressure. The muscle walls are able to contract to force the blood along through the arteries.Veins are made up of a much thinner, less muscular wall compared to the arteries. The blood in the veins is nether considerably much lower pressure compared to the blood in the arteries, this is because arteries require higher pressure in order to deliver the oxygenated blood to the arterioles, capillaries, other organs and tissues and to also prevent the back flow of blood, veins dont require this high pressure because the de-oxygenated blood goat travel from the tissues to the heart through the veins with the sponsor of the muscle contractions. One of the functions of the veins is to ensure that the blood doesnt flow back towards the heart, veins drive valves every few centimetres along, this aids them push the blood in one direction. besides muscle contraction and relaxation can also occur to help squeeze the walls of the veins to help the blood flow back towards the heart when necessary. You can use a stethoscope to hear pulmonary circulation. The sounds that are audible are the ventricles contracting and the valves closing.Capillaries are the littlerest of all the blood vessels they have a wall that is one cell thick, capillaries connect the arterioles and venules this is where all the exchange of nutrients and gases such as oxygen and carbon dioxide occurs- through the capillary surfaces. Leucocytes are able to leave our capillaries in order to digest any micro-organisms that could be a capability threat or disease.Arteries, veins and capillaries are all blood vessels of the body and all of them are routes for the blood to pass through to provide their functions. They all admit tunica externa, tunica media and tunica intima.Blood is carried away from the heart via the arteries and the blood returns to the heart through the veins. Our circulatory system is a transport system the carries our blood, oxygen and waste products to and from our bodys cells in order for our bodies to functions. (2) During systemic circulation, blood passes through the kidneys. This phase of systemic circulation is known as renal circulation. During this phase, the kidneys filter much of the waste from the blood. Blood also passes through the small bowel during systemic circulation. This phase is known as portal circulation. During this phase, the blood from the small intestine collects in the portal vei n which passes through the liver. The liver filters sugars from the blood, storing them for laterWhen it comes to love regulation in order to keep imperturbable our capillaries are satisfactory of forcing the blood supply to the surface of the skin, this allows the air to reach the blood and to cool it more easily, and sweating is also induced as part of the heart regulation. However when trying to keep warm our capillaries work hard in order to reduce the blood at the skin surface and sweating is also reduced. This is known as vasoconstriction and vasodilation. Heat regulation is one of the bring out functions of the circulatory system as well as many other functions. Signals along nerves from the hypothalamus control both vasodilation and vasoconstriction. It is necessary for the human body to have vasodilation and vasoconstriction as it regulates the bodys blood pressure, by constricting and releasing the vessels to allow more or less blood through, for example whilst exerci sing our heart and breathing rates increase and blood vessels in our limbs dilate in order to deliver more oxygenated blood to our working muscle cells. (3) Vasoconstriction is the limiting of the blood vessels resulting from contraction of the muscular wall of the vessels, particularly the large arteries and small arterioles. The process is the opposite of vasodilation, the widening of blood vessels. The process is particularly principal(prenominal) in staunching haemorrhage and acute blood loss. When blood vessels constrict, the flow of blood is restricted or decreased, thus, retaining body heat or increasing vascular resistanceOur blood that is carried virtually in our cardiovascular system is responsible for maintaining its levels in many advance ways. For example haemostasis is a complex drawstring reaction that produces the blood to constipate this is otherwise known as coagulation. The body clots in two different ways, there is the normal clot which is a good manikinat ion that stops bleeding, and there is also a thrombus which is bad as it can block the blood vessels.The endothelium is the cells that create the vessel wall. When the endothelium becomes damaged, for example, when a cut breaks through the wall, collagen fibres then start to appear. These collagen fibres are a protein that is vital for the structure of the vessel wall, these fibres then allow platelets to attach themselves, these are produced from precursor megakaryocytes, its these platelets that lead to the formation of blood clots.The platelets become activated and stupefy to release a chemical called Thromboxane A2 which calls on more platelets to the area. Fibrin, which is the insoluble form of the soluble protein fibrinogen, is then converted by thrombin. The fibrin begins to appear and layers on top of the platelets which start to fuse them together. This fibrin helps the clot form as the red blood cells stick to the fibrin. This process then repeats until the clot is fully formed. This process is measurable for the cardiovascular system, this is because the average human contains around 4.7 to 5.7 litres of blood, if around 30%-40% of this is anomic it could prove fatal or cause severe damage.The blood the is carried around the cardiovascular system, is made of erythrocytes, leucocytes, platelets and plasma which is mainly water, amino acids, proteins, carbohydrates, lipids, hormones, vitamins, electrolytes, dissolved gases, and cellular wastes. Erythrocytes contain a globular protein called haemoglobin which allows oxygen to bind to it this allows the erythrocytes to transport oxygen throughout the body and organs. The haemoglobin molecule is made up of 4 polypeptide chains, 2 containing 141 amino acids and 2 containing 146, attached to each polypeptide chain is a molecule that contains iron and is known as a haem, the function of this molecule is to absorb oxygen until it is fully saturated. Carbon dioxide however binds to the amino acids and not the erythrocytes, this means that is binding to the proteins and not the haem.