Jack M. Walter, age 11, of Allentown, Pennsylvania, for his question:
What exactly are corpuscles?
The word corpuscle is related to the words "corpse" and "corns." All three are descended from a Latin ancestor meaning body. A corpse is a lifeless body, a corps may be a body of soldiers. A corpuscle is a busy little midget of a body called a living cell.
A cell called a corpuscle lives a life of its own, but its duties are performed in teamwork with a large assortment of other living cells. It is free to float in the liquid plasma of the blood stream. But it must work with the fixed cells in tissues and organs throughout the entire body. These fixed and specialized cells carry on fabulous chemical activities. They need fuel and raw materials to perform these life activities. And such fuel consuming activities leave ashes in the form of waste chemical materials. Cells of tissues and organs are fixed in place which means they cannot shot around for their raw materials, or leave home to dispose of their trash. These toting duties are done by the mobile corpuscles.
Your blood stream circulates trillions of these traveling corpuscles throughout your body. There are several different kinds designed to perform different duties. Biologists usually call them all blood cells because they float in the blood stream. There are special names for each of the various types. Most of them are red blood cells called erythrocytes. This scientific term is coined from two words meaning "red" and "cell" and it is pronounced as if it were spelled ee rith row site. The various white cells are called leucocytes, meaning "light cells." The blood stream also carried a quota of miniature plate shaped cells called platelets.
Most of the blood cells are erythrocytes that perform the vital job of toting oxygen and nourishment to the tissues and removing their waste products. The various leucocytes act as armies to protect and defend the body against disease and invading bacteria. The tiny platelets rush to wounded tissues. They aid the blood in forming clotted wads to stop the bleeding. The red cells outnumber the other corpuscles by about 700 to one. But virus and bacteria invasions trigger the body to increase its armies of defending leucocytes. A patient may have a blood count taken that shows the ratio of erythrocytes and leucocytes. When the white blood cell count is higher than normal, the patient is coping with some sort of infection.
The corpuscles themselves are nourished by chemicals dissolved in the liquid blood plasma. Most of them are created in the soft marrow of the bones. After their tours of duty, they go to the body's disposal departments. The little red cells live the busiest lives, fetching and carrying without rest. In three to four months they are ready to be scrapped and replaced. Every second, many millions of your old erythro¬cytes are replaced by new ones. When you are sick, millions of new leucocytes are created and rushed into action. Their life expectancy ranges from a few minutes to several days.