What is the functions of heart explain theirs functions and mechanism?

Dear student
Functions of the heart:
(i) It helps in the circulation of oxygen rich blood throughout the body by the pumping.
(ii) It receives oxygenated blood from the lungs.
(iii) It also pumps back the blood carrying carbon dioxide to the lungs.
(iv) It shows rhythmic contraction and relaxation for movement of blood.

Heart is the organ in our body which belongs to circulatory system. 1) It pumps the blood (not purifies). 2) The deoxygenated blood from the body reaches the heart through the veins in the left auricle. 3) The blood then passes to left ventricle through contraction and relaxation. 4) The blood is then transferred into lungs through the pulmonary artery. 5) The lungs purifies the blood by making it oxygenated. 6) Through pulmonary veins the blood again enters heart in right auricle. 7) The blood is then passed into right ventricle. 8) Then finally through the Aorta (largest artery) oxygenated blood is pumped into the body. 9) This is the whole mechanism and this mechanism is known as DOUBLE CIRCULATION OF BLOOD.