Divisions Of Circulation:
Blood flows through two divisions of circulatory system:
- Systemic Circulation
- Pulmonary Circulation
1- Systemic Circulation:
Systemic circulation is otherwise known as greater circulation. Blood pumped from left ventricle passes through a series of blood vessels, arterial system and reaches the tissues. Exchange of various substances between blood and the tissues occurs at the capillaries.
After exchange of materials, blood enters the venous system and returns to right atrium of the heart. From right atrium, blood enters the right-ventricle. Thus, through systemic circulation, oxygenated blood is supplied from heart to the tissues and venous blood returns to the heart from tissues.
2- Pulmonary Circulation:
Pulmonary circulation is otherwise called lesser circulation. Blood is pumped from right ventricle to lungs through pulmonary artery. Exchange of gases occurs between blood and alveoli of the lungs at pulmonary capillaries. Oxygenated blood returns to left atrium through the pulmonary veins.
Thus, left side of the heart contains oxygenated or arterial blood and the right side of the heart contains deoxygenated or venous blood.