The venous system within the cardiovascular system

The venous system is an integral part of the cardiovascular system which is designed to circulate blood allowing gaseous and metabolic exchanges within the billions of cells making up the body.
The cardiovascular system is a closed circulatory system in which blood flows in one direction only. It is organised around a central organ – the heart pump – and is made up of three different types of blood vessels (arteries, veins and capillaries).

The arterial system carries blood from the heart to the tissues and organs and the venous system carries blood back to the heart (read more...)
The arteries and veins are linked by microscopic capillaries, where oxygen, carbon dioxide and metabolite exchanges occur.

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Blood travels on two different routes through the circulatory system :


  • The general arterial circulation, which originates from the left heart, carries oxygenated blood, nutrients, hormones and immune system messengers, etc. in the arteries, towards the organs and peripheral extremities. Oxygen-depleted blood and waste are then carried back to the heart through the venous circulation.

  • The pulmonary circulation, which originates from the right heart, takes oxygen-depleted blood to the pulmonary capillaries in the lungs where gaseous exchange takes place with the air contained inside the pulmonary alveoli, The now oxygenated blood returns to the heart via the pulmonary veins. These are the only veins which carry oxygenated blood.