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Describe the mechanism of breathing in human. Being |
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Answer» Breathing consist of inhalation and exhalation. Inhalation means taking air in, to get oxygen and exhalation means expelling air out to release carbon dioxide. A breathe means one inhalation and one exhalation. It involves the movement of ribcage and diaphragm. Diaphragm is made up of muscles which form the floor of chest cavity, where lungs are situated.Steps of breathing mechanism in humans:i) Inhalation:\xa0During inhalation rib cage moves up and out and, diaphragm contracts and move down. This leads to increase in space of chest cavity and decrease in pressure of lungs. Then air goes into lung to fill the space with air.ii) Exhalation: Exactly reverse of inhalation occurs in exhalation. Rib cage moves down and inwards, whereas diaphragm relaxes and moves up. This reduces the size of chest cavity and increase in pressure, so air is pushed out of the lungs. When we inhale air,it passes through our nostrils into the nasal cavity. from the nasal cavity,the air reaches our lungs through the wind pipe.lungs are present in the chest cavity.this cavity is sorrounded by ribs.a large muscular sheet called diaphram forms the floor of the chest cavity.breathing involves the movement of the diaphram and the rib cage.during inhalation,ribs moves up and outwards and diaphram moves down.this movement increases space in our chest cavity and air rushes into the lungs.the lungs get filled with air.during exhalation,ribs move down and inwards while diaphram moves up to its former position.this redues the size of the chest cavity and air is pushed out of the lungs. |
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