237.WHAT IS ASTHMA?
Asthma is not a disease itself, but a symptom of some other condition. When a person has asthma, he finds it hard to breathe because there is an obstruction to the flow of air into and out of the lungs.
This barrier or obstruction may be caused by a swelling of the mucous membranes, or by a constriction of the tubes leading from the windpipe to the lungs. When a person has an attack of asthma, he develops shortness or breath, wheezing, and coughing. The attack may come on gradually or develop suddenly.
236.WHAT IS AN ANTIBODY?
Bacteria are the most widespread creatures in the world. Everything we touch, every breath of air contains millions of them. About 80 per cent of all bacteria are harmless. A small percentage is actually useful to us, and a small group of them are harmful to human beings.
Since man is constantly taking in bacteria of all kinds, it is obvious that our body and these bacteria form a kind of “working” relationship. Our body supports colonies of bacteria and in turn these bacteria may perform useful functions, such as helping to decompose food.
235.WHAT IS A POLLEN COUNT?
During the “hay fever season,” newspapers in many cities publish the day’s pollen count: What is pollen, what does it have to do with hay fever, and what is a pollen count?
A person is said to have hay fever when he is sensitive to pollen and some other sum stances that are present in the air. Pollen is the reproductive element of plants and is contained in the flowers of most plants. Usually, it occurs as a fine dust or grains.
