Respiratory System - Causes and problems

THE RESPIRATORY SYSTEM

 MAN CAN survive for weeks without food, for days without water, but for only a few minutes without air. Air must reach the lungs almost constantly so that oxygen may be extracted there and distributed via the blood to every body cell. Even in a relaxed state, you breathe in and out 10 to 14 times a minute, with each breath lasting 4 to 6 seconds. In the space of a minute, you take in 9 to 12 pints of air. The fact is that the body has small reserves of oxygen, all of it consumed within less than half a minute after the start of vigorous exertion. And with such exertion, the need for air increases many fold so that yours breathing rate may speed up to one second per breath and a total intake of 20 gallons of air a minute. 

You can figure roughly that in a normal day you will breathe in some 3,300 gallons of air-enough to occupy a space about 8 feet by 8 feet by 8 feet-and, in a lifetime, you will consume a prodigious quantity, enough to occupy 13 million cubic feet of space. The respiratory system is one, of course, that you will want to under- stand well. It is a system in particular that you can do much to guard through knowledge of how it functions, what can go wrong, and the preventive techniques available for you to use.

THE NOSE

Respiration begins with the nose, which is specially designed for the purpose, although there will be times when you breathe through the mouth as well. As you read this, you are quietly, with little or no awareness, breathing lightly through your nose. When you race for a bus or train, or perform any vigorous activity, and begin to puff and pant, you are breathing rapidly through the mouth to provide the blood with the extra oxygen needed. The mouth, however, is not designed for breathing. You may have noticed this on cold days when you make a deliberate effort to keep your mouth tightly closed, because if you take air in through the mouth you can feel its coldness.

Cold air passing through the mouth has no chance to become properly warmed. But cold as the air may be, you can breathe comfortably through the nose. The nose, acting somewhat like an air conditioning system, regulates the temperature and humidity of air passing through and filters out foreign particles as well. Air enters, of course, through the nostrils. Hairs around the nostril openings catch dust and other impurities. The nostrils are separated by a partition, the septum, which is made of cartilage-a flexible kind of bone -in the lower part of the nose, and of real bone in the upper part. Thus, while you can pull the bottom part of the nose from side to side, the top part is immovable.