The Transport System in Human

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The transport system in human is called circulatory system. The human circulatory system is a called double circulatory system because the blood flows through the heart twice in a complete circuit. The human double circulatory system consists of the pulmonary circulation which transports blood between the heart and the lungs and the systemic circulation which transports blood between the heart and all other parts of the body.

A circulatory system has four basic characteristics, Circulating fluid, pumping device, blood vessel and valves. The circulating fluid is called blood which transports useful and waste materials. Pumping device is the heart; blood is moved through the body by muscular contractions of the heart. Blood vessels are a complex network of blood vessel carries materials to the tissue and back to the heart. There are three main types of blood vessels; arteries, veins and capillaries. Valves are present in some blood vessels to prevent backflow and ensure that bloods flows in one direction only.