The cardiovascular system - Assignment Example

Consequently, blood goes to both directions in the body for each pump. The four major chambers of the heart are; the left atrium, left ventricle right atrium, and right ventricle. The deoxygenated blood that is from the body is usually pumped into the right ventricle and the right atrium through to the lungs (Evans & Sutton 2012, p. 13). On the other hand, from the lungs, the oxygenated blood is pumped into the left ventricle and the left atrium into the body. Both left and the right parts of the heart functions together to ensure the flow of blood all over the body.

From the right part of the heart, blood enters the heart via the main vena cava and the inferior vena cover hence emptying the deoxygenated blood coming from the body into the right atrium. While the right atrium contracts, blood flows from the right atrium to the left ventricle via an opening called the tricuspid valve. However, when the ventricle is filled with blood, the valve shuts hence prevents the backward flow of blood into the atria as the ventricle contracts. Due to the contraction of the ventricle, the heart releases blood via the pulmonic valve then to the pulmonary artery and eventually to the lungs where it gets oxygenated (Evans & Sutton 2012, p. 34). On the left side of the heart, pulmonary vein empties the blood rich in oxygen from the lungs to the left atrium.

Due to contraction of the left atrium, blood flows from the left atrium then into the left ventricle via an opening called mitral valve. The valve then shuts once the ventricle is filled preventing the flow of blood backward. With the contraction of the ventricle, blood flows out of the heart via the aortic valve through aorta then into the body. The rhythmic contraction of the heart occurs spontaneously, even though the rate of contraction may be changed by the hormonal or nervous influences.

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