Question

explain the working of heart

Answer 1

Our Heart is around the size of a fist divided into four chambers namely two ventricles and two atria, as discussed above. There is one ventricle and one atrium on the left side and the other atrium and ventricle towards right side. The ventricles are the chambers that pump blood and atria are the chambers that receive blood. Deoxygenated blood is received by the right atrium from the superior vena cava that leaves blood from the veins of the upper arms and organs. The blood is also received via inferior vena cava that leaves blood from the veins of legs and lower organs. Also, the right atrium receives blood from the coronary sinus, that leaves deoxygenated blood from the heart.

The right ventricle pumps the blood to the lungs for re-oxygenation when it is filled through the pulmonary arteries. The right semilunar valves close and prevent the blood from the pulmonary veins, after blood passes through the pulmonary arteries. Then the oxygenated blood is received by the left atrium from the lungs via pulmonary veins.

Answer 2

The heart muscle contracts in two stages to squeeze blood out of the heart. This is known as systole.

In the first stage, the upper chambers (atria) contract at the same time, pushing blood down into the lower chambers (ventricles).Blood is pumped from the right atrium down into the right ventricle and from the left atrium down into the left ventricle.In the second stage, the lower chambers contract to push this blood out of the heart to either the body via your main artery (aorta) or to the lungs to pick up oxygen.

The heart then relaxes – known as diastole. Blood fills up the heart again, and the whole process, which takes a fraction of a second, is repeated.

The different sides of the heart have different functions.

On the right side, the upper chamber fills with oxygen-depleted blood from your body and pushes it via the lower chamber and the pulmonary artery back to the lungs. Here blood picks up oxygen and releases carbon dioxide.On the left side, the upper chamber fills with oxygen-rich blood from the lungs. This is pumped via the lower chamber into the aorta and out to the body to provide cells with the crucial oxygen they need.