The body requires a precise atmospheric pressure to maintain its gases in solution and to facilitate respiration—the intake of oxygen and the release of carbon dioxide. Humans also require blood pressure high enough to ensure that blood reaches all body tissues but low enough to avoid
One importance is life because we cannot breathe without air pressure.
When we breathe in we expand the volume of our lungs; this lowers the air pressure of the air that’s in our lungs (we don’t breathe everything out, there’s a little left) and our open airway to the outside world (our windpipe, or trachea to give it its proper name, and nose and mouth) means the outside air, which is now at a higher pressure than the air pressure in our lungs, wants to equalise and therefore air is pushed in, by the atmosphere, into us. This is breathing in.
When we’re ready to breathe out the opposite happens: our breathing muscles go the opposite way, this squashes our lungs, thus the air within is squeezed, gas when squeezed has a higher pressure, we have an open airway (if we don’t i.e. we’ve closed our mouth and pinched our nose then at this point we can start to make our faces red) and therefore the air within our chest cavity is at a higher pressure than its counterpart outside of our body and again the two can equalise so the air in our lungs goes outside our body. This is breathing out.
Without the facility of air pressure, we could not breathe in and out. damage to blood vessels.
