How Does The Respiratory System In Man Work?
A man can live without food for a few days, but without air he cannot live even for five minutes. The moment he is born he begins to breathe will continue to breath till he is alive. During the process of breathing he draws some are into his body and expels some. If this supply if air is cut off, he is suffocated and dies. The air we breathe in is taken into the lungs through the wind pipe. The lunge are situated in the chest-one in each side of the body. The air we breath in contains oxygen to the extent of one-fifth of the volume of air. The oxygen is dissolved in the blood and is carried to all parts of the body. The oxygen combines with the tissues and sets free the energy contained in them. The combination of oxygen with a substance is known as the process of oxidation, combustion or burning is going on in the human body every moment of the life of a man-whether he is awake or asleep. Heat is, of course, generated, but there is no fire. The whole system of respiration can be summarized as follows : (1) Pure blood received from the lungs is pumped by the heart into the large arteries. (2) Veins bring impure blood from various parts of the body and pour it into the heart. (3) The heart pumps it out into the lungs for purification. Thus a cycle is formed and the process is automatic. Lungs are the most important part of this system, because it is they that purify the impure blood and discharge waste products like carbon dioxide. The other parts of the respiratory system are : (a) the nose. (b) The upper part of the wind-pipe which is modified into the voice box known as larynx. (c) The wind-pipe. (d) The lungs.
