Causes of Human Diseases

Parasites Cause Diseases

Altogether there are more than 1700 known human diseases. Many of them are not serious. A few are serious, and widespread; they are responsible for millions of deaths each year. Among them are such diseases as pneumonia, influenza, tuberculosis, malaria, and yellow fever. Man must always be on guard against them.

Parasites are the causes of much human disease and suffering. Several hundred kinds are able to enter the human body and live in it. They may then be spread from one person to another. That is why the diseases which they cause are said to be communicable.

Disease Bacteria

            Bacteria make up one large group of such Parasites. As you know, they are microscopic plant which cannot make their own food. Parasite bacteria find the human body a good place in which to live. They multiply rapidly. Some kinds give off poisons in the body, which make us ill. Others attack and destroy body tissues, causing sickness in that way.

Certain kinds of microscopic plants live on the skin rather than in the body. Parasites of this type cause the skin disease known as ringworm; athlete’s foot is another disease caused by these parasites. Usually these may lead to dangerous infections.

Science and Health

_One hundred Years of Progress

Modern Life

Many of the things which you see every day were unheard of a hundred years ago. Suppose that by some miracle a man who lived then were to visit your home today. As evening came he would look for the oil lamps to be lit. Can you imagine his astonishment as you turned on the electric lights? After supper you might step to the radio, turn a switch, and tune in a station. Your guest would be bewildered upon hearing the jokes of a comedian or the music of an orchestra playing in a city a hundred miles away. He would be deeply puzzled as you changed from station to station by merely pushing a button. He might event think that some magic was involved.

Interesting Science Experiences

Interesting Science Experiences

1. Can you locate the star groups, such as the big Dipper, the Little Dipper, and others? If you can obtain a series of star maps, one for each season of the year, you may wish to study the night sky. Pick a clear, dark evening, and go as far away from any light as you can.
2. Have you ever tried taking photographs of the Milky Way, or of other groups of stars? An ordinary camera will do. Load the camera, set the shutter so that it is wide open and stays that way, and then put the camera on a firm box. Make sure it is pointing at a star or group of stars. Let the shutter stay open two hours or longer, if possible. What kind of pictures did you get? Be sure to do this on a moonless night, and away from electric lights.
3. Watch the newspapers and magazine for articles about the new telescope at Mt. Palomar. Your class might be interested in hearing you tell them what is in the articles that you find.