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Cancer |
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Cancer.
We've all heard of it. But what exactly is this strange disease? The
truth is, it is a mutation. Cancer starts when a cell mutates. A cell usually is a complete copy of the parent cell unless a mutation occurs during mitosis. This means that the hereditary material of the cell is different from that of the parent cell. In other words, the new cell will behave and possible look different from its parent cell. Sometimes a mutation also occurs when a cell is exposed to harmful materials like raditation. One of the most common mutations cause cells to reproduce when the two new cells are not needed. This causes the cell to reproduce rapidly, and the new, mutated cells quickly outnumber the old cells. The tumor will still be extremely small after ten years and a second mutation may have occurred. This may cause the cells to reproduce even more rapidly. Then another mutation may arise, such as disabling a cell's self-destruct (the self-destruct causes a cell to explode when it has been compromised). This causes the cell to reproduce even faster. Then a few more mutations may arise. Soon, however, the tumor will break through the cells' membrane, which provid a barrier. Now that the tumor has access to the blood vessels, angeogenisis, or the growth of new blood vessels, occurs. With the nutrients the blood vessels provide, the tumor grows faster still. The tumor also begins to send smaller tumor cells into the blood stream. By this time the tumor is now big enough to be detected, although not identified, where as it was previously small enough to avoid detection, it is about as big as a small grape. A tumor with the weight of a gram can discharge over a million tumor cells into the blood stream each day. There is a very small chance of the survival of these tumors. This is called metastasizing and it is what makes tumors so deadly. While only one in 10,000 cells survive, one more colony is all it takes to kill someone. The deaths are caused by the tumors eventual interference with the body's functions. |
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