The two sides of the heart work together. The relaxed or resting period of the heart chambers, especially the ventricles, is known as diastole.
While the period when the chambers, especially the ventricles, contract is known as systole.
The two auricle relax at the same time to receive blood from the respective veins. The blood entering the auricles is at low pressure. The auricle contract causing the biscupid and triscupid valves to open, and the opening of the vein to close. The blood then flow into the relaxed ventricles. Almost at once, the ventricles contract. Backflow of blood into the auricle is prevented by the sudden closing of the biscupid and triscupid valves.
We hear the closing of these valves as a loud 'lub' sound in a heartbeat. Blood from the ventricles enters the arteries. After fully contracting, the ventricles start to relax. The blood in the arteries tend to flow back into the ventricles. This is prevented by sudden closing of the semi-lunar valves. We hear the closing of these of this valves as a soft 'dub' sound in a heartbeat. Thus, one complete heartbeat consists of one contraction (systole) and one relaxation (diastole) of the ventricles, and lasts for about 0•8 seconds.
Pulse: Each time the ventricles contract, they force blood into the arteries (already filled with blood) at high pressure. When this happens, the elastic walls of the arteries dilate suddenly. Then when the ventricles relax and the semi-lunar valve close, the walls of the arteries recoil, and at the same time the muscles in these wall contract. These two force cause blood to flow away from the heart in a series of waves. Each wave is called pulse. We can feel it by placing a finger over an artery which lies near the surface of the skin, such as the arteries at the wrists and neck.
While the period when the chambers, especially the ventricles, contract is known as systole.
The two auricle relax at the same time to receive blood from the respective veins. The blood entering the auricles is at low pressure. The auricle contract causing the biscupid and triscupid valves to open, and the opening of the vein to close. The blood then flow into the relaxed ventricles. Almost at once, the ventricles contract. Backflow of blood into the auricle is prevented by the sudden closing of the biscupid and triscupid valves.
We hear the closing of these valves as a loud 'lub' sound in a heartbeat. Blood from the ventricles enters the arteries. After fully contracting, the ventricles start to relax. The blood in the arteries tend to flow back into the ventricles. This is prevented by sudden closing of the semi-lunar valves. We hear the closing of these of this valves as a soft 'dub' sound in a heartbeat. Thus, one complete heartbeat consists of one contraction (systole) and one relaxation (diastole) of the ventricles, and lasts for about 0•8 seconds.
Pulse: Each time the ventricles contract, they force blood into the arteries (already filled with blood) at high pressure. When this happens, the elastic walls of the arteries dilate suddenly. Then when the ventricles relax and the semi-lunar valve close, the walls of the arteries recoil, and at the same time the muscles in these wall contract. These two force cause blood to flow away from the heart in a series of waves. Each wave is called pulse. We can feel it by placing a finger over an artery which lies near the surface of the skin, such as the arteries at the wrists and neck.
quite educating
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