Question

Explain the flow of blood in the heart.

Answer 1

The size of heart is approximately the size of a closed fist and is located between lungs in the middle compartment of lungs. Heart is made up of cardiac nucleus. The heart is a dark red to brown colored muscular organ in most animals which pumps blood through blood vessels of the circulatory system.

Complete answer:
Heart is a muscular organ that continuously undergoes contraction and relaxation to pump blood through blood vessels. In mammals such as humans, the heart is divided into four chambers. The upper portions of the heart are called as atria or auricles and are differentiated into left and right auricles of atria. The lower chambers of the heart are called ventricles and are differentiated into left and right ventricles.

The blood is carried by certain pathways called as blood vessels inside our body; they are arteries and veins. Arteries carry oxygenated blood and veins carry deoxygenated blood. Heart along with blood vessels constitute the circulatory system.

a) The right atrium receives deoxygenated blood from the body and transfers it to eight ventricles through a tricuspid valve. The right ventricle pumps deoxygenated blood to lungs through the pulmonary valve.
b) The left atrium receives oxygenated blood from lungs and pumps it to the left ventricle through the mitral valve or bicuspid valve. The blood is then pumped through an aortic valve to rest the body.
c) The right ventricle pumps the blood to the lungs where it is reoxygenated via the pulmonary arteries. The right semilunar valves are closed in order to prevent blood from flowing back into the heart.
d) The left ventricle helps in pumping of oxygen - rich blood which it receives from the left atrium and it pumps the oxygenated blood through the ventricle throughout the body.

Note: Since blood passes through the heart twice, it is called double circulation. Left ventride is strongest as it pumps blood out to the entire body. pumping of blood is an involuntary activity. A few facts about heart are,
i) In one day around 5.7 litres of blood in a day throughout the body.
ii) An adult heart which beats around 60 to 100 times per minute.
iii) The heart is present slightly tilted towards to the left side.