To transport oxygen from the alveoli to where it is needed-cells around the body, and this is achieved in the protein haemoglobin.
We need nutrients and oxygen to be supplied to our cells at a very fast rate as our cells need a lot of energy to keep us alive. Therefore we must have an efficient transport system to transport nutrients and oxygen to the billions of cells in our body. The transport system in man is known as the circulatory system. The human body needs iron for oxygen transport. Oxygen (O 2) is required for the functioning and survival of nearly all cell types (mature erythrocytes being one exception). Oxygen is transported from the lungs to the rest of the body bound to the heme group of hemoglobin in erythrocytes.  Haemoglobin [edit]. The main role of the transport system is to transport oxygen from the alveoli to where it is needed-cells around the body, and this is achieved in the protein haemoglobin. Each haemoglobin molecule can hold four oxygen molecules. The function of the arteries is to transport blood swiftly and at high blood pressure to the tissues. Look at the diagram on the right. It is of a artery and shows three things-the tunica intima, the tunica media and the tunica externa. Relevance. Rating Newest Oldest. Best Answer: Well, it's kinda complicated. We transport oxygen, food and waste through our blood supply with a four-chambered heart. The left half of the heart pumps blood to the lungs and back to the right half, which forces it through the rest of the body. If it's headed towards the heart it's a vein and if it's going away it's an artery.  Iron is required for the production of red blood cells (a process known as haematopoiesis), but it's also part of haemoglobin (that is the pigment of the red blood cells) binding to the oxygen and thus facilitating its transport from the lungs via the arteries to all cells throughout the body.  If we didn't have a transport system organs wouldn't get the oxygen, the nutrients and Glucose they require for the body to function properly. Rating Newest Oldest. Best Answer: We have a complictaed body where different parts (organs) do different jobs.. in the simplest organisms..every part of the organism can feed, breathe, excrete and so on. The human transport system is a system of tubes with a pump and valves to ensure one way blood flow. We need a transport system to deliver oxygen, nutrients and other substances to all our body cells, and take away waste products from them. The oxygenated blood (high in oxygen, red in color) comes to the heart from the lungs in the pulmonary vein; the heart pumps it to the aorta (an artery) to the rest of the body. The function of the red blood cells is to transport oxygen from the lungs to the body cells. A red protein called Haemoglobin, when the blood reaches the lungs, oxygen diffuses from the alveoli to the red blood cells and combines with haemoglobin forming an unstable compound called oxyhaemoglobin. The human body is about two-thirds oxygen. Oxygen's influence and its role in Human Body. Oxygen's influence and its role in Human Body. In the human body, the oxygen is absorbed by the blood stream in the lungs, being then transported to the cells where an elaborated change process takes place. Oxygen plays a vital role in the breathing processes and in the metabolism of the living organisms. 
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why is it necessary that we have a transport system in the human body