explain the working of heart
Answers
The heart is a muscular organ. It works as a pump in the circulatory system. It is located in the middle of the chest and tilts towards the left.
The heart is made up of cardiac muscle. There are 4 Chambers in a heart. The 2 upper chambers (atria) are thin walled and 2 lower chamber (ventricles) are thick walled. Right and left side of the heart is separated by the septum. Between atria and ventricles is an aperture which remain closed by valves. Valves prevent the back flow of blood. Oxygenated blood is separated from deoxygenated blood to allow an efficient supply of O2 to the body of the high energy needs as in bird and mammals.
Amphibians and reptiles have 3 chambered heart - oxygenated and deoxygenated blood are not completely separated because body temperature varies with environment.
Fishes have 2 chambered heart and blood is deoxygenated in the gills heart pumps the blood only once.