Explain the structure of human heart and function 0
Answers
Human heart is a mesodermaly derived muscular organ, present in thorscis cavity between the two lungs protected by a double membrane of pericardium.It is 4 chambered_ 2 auricles(upper) and 2 ventricles(lower).Interartrial septum seperates the left and rifht auricles.Interventrical septum seperates the right and left ventricle.The opening between right auricle and right ventricle is guarded by 3 mascular flap or cusps called tricuspid valve and the opening between the left auricle and ventricle is guarded by bicuspid or mitral valve.The opening of right and left ventricle to pulmonary artery and aorta respectively is controlled by three semilunar valve.The nodal tissue present on upper right corner of right atrium is called SAN(sino auricular node) and on lower left corner of right atrium is called AVN(auriculo ventricular node).From AVN arises a bundle of histone which consists of right and left branches called purkinje fibres.SAN generates action potential and is responsible for rhythemic contaction of heart.Therefore it is called pacemaker.
Answer:
Heart plays a very important role in the supply of oxygenated blood to different parts of the body. Deoxygenated blood is collected from various parts of the body and is transferred to the heart. The blood enters the heart through the pulmonary valve and enters the right atrium, then it goes to the right ventricle through the tricuspid valve. From here the blood then goes to the lungs for oxygenation. Oxygenated blood is then brought back to the heart with the help of pulmonary veins and enters the left atrium. The blood then goes to the left ventricle through the bicuspid valve and then transferred to the aorta through the aortic valve for further circulation of blood to different parts of the body.
The heart blood flow diagram (flowchart) given below will help you to understand the pathway of blood through the heart.Initial five points denotes impure or deoxygenated blood and the last five points denotes pure or oxygenated blood.
1.Different Parts of the Body
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2.Major Veins
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3.Right Atrium
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4.Right Ventricle
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5.Pulmonary Artery
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6.Lungs
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7.Pulmonary Veins
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8.Left Atrium
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9.Left Ventricle
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10.Aorta
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11.Different Parts of the Body
