| In today's modern world, we are products of a highly | | | | that scientists have really begun to gain even a |
| technological era, surrounded by machines designed | | | | rudimentary understanding of this valuable and |
| to serve every imaginable purpose. The list of | | | | intricate system. |
| mechanical wonders is endless: dishwashers, | | | | Two main components of the immune system |
| refrigerators, telephones, computers, automobiles - all | | | | include the bone marrow (which produces white |
| have become commonplace in our everyday lives. In | | | | blood cells or leukocytes, that circulate throughout |
| fact, it's difficult to imagine going without these | | | | the body to detect and destroy harmful substances) |
| modern conveniences. Unfortunately, when a machine | | | | and the thymus (a small organ located above the |
| breaks down, it does not have the capacity to repair | | | | heart that serves as a sort of training center for |
| itself, no matter how advance or well-designed it | | | | immune cells). Specialized cells of the immune system |
| may be. We must either replace the item, or seek | | | | include B cells (which produce antibodies against |
| out the help of someone with specialized knowledge | | | | infectious agents), T cells (which are specially trained |
| to fix the faulty machine. But one machine does exist | | | | by the thymus to recognize the specific invaders), |
| that comes with its own built-in and highly specialized | | | | natural killer cells (which wonder through the body |
| repair mechanism: The Human Body. | | | | and attack cancerous cells) and phagocytes such as |
| Through an organic rather than technological wonder, | | | | the monocyte and macrophage ; also known as |
| the human body is nevertheless an intricate and | | | | "eating cells" (which engulf and destroy |
| sophisticated machine, made all the more remarkable | | | | microorganisms and debris). Together, these various |
| because every human is different and unique. When | | | | cells create a strong defense against any substance |
| the body "breaks down", falling victim to illness and | | | | that threatens the health of the body. |
| disease, it is not possible to simply go out and replace | | | | In 1979, immunologist Edwin Blalock discovered that |
| it with a new one. Luckily, the body comes equipped | | | | immune cells manufacture several hormones which |
| with its own mechanism of defense and repair in the | | | | enable the immune system to coordinate its activities |
| form of an elaborate immune system. | | | | with the bodys' other systems. All of these systems |
| The immune system is a complex network of cells | | | | work in tandem to keep us healthy and protect us |
| and organs, not confined to any one area of the | | | | from threat of foreign substances. The human body |
| body. It is programmed to fight off any foreign | | | | is a marvelous but irreplaceable machine and the task |
| substance that threatens the health of the body. In | | | | of the immune system is to provide the body with |
| addition, the immune system clears away dead cells | | | | superior protection, helping this machine to last a long, |
| and destroys mutant or altered cells that could | | | | long time. |
| become cancerous. It is only within the past 30 years | | | | |