Cancer is the general name for a group of more than 100 diseases in which cells in part of the body begin to grow out of control. Although there are many kinds of cancer, they all start because abnormal cells grow out of control. Untreated cancers can cause serious illness and even death.
Normal cells in the body
The body is made up of trillions of living cells. Normal body
cells grow, divide into new cells, and die in an orderly fashion. During the
early years of a person’s life, normal cells divide faster to allow the person
to grow. After the person becomes an adult, most cells divide only to replace
worn-out or dying cells or to repair injuries.
How cancer starts
Cancer starts when cells in a part of the body start to grow out
of control. There are many kinds of cancer, but they all start because of
out-of-control growth of abnormal cells.
Cancer cell growth is different from normal cell growth. Instead
of dying, cancer cells continue to grow and form new, abnormal cells. Cancer
cells can also invade (grow into) other tissues, something that normal cells
cannot do. Growing out of control and invading other tissues are what makes a
cell a cancer cell.
Cells become cancer cells because of damage to DNA. DNA is in
every cell and directs all its actions. In a normal cell, when DNA gets damaged
the cell either repairs the damage or the cell dies. In cancer cells, the
damaged DNA isn’t repaired, and the cell doesn’t die like it should. Instead,
this cell goes on making new cells that the body doesn’t need. These new cells
all have the same damaged DNA as the first cell does.
People can inherit damaged DNA, but most DNA damage is caused by
mistakes that happen while the normal cell is reproducing or by something in
our environment. Sometimes the cause of the DNA damage is something obvious,
like cigarette smoking. But often no clear cause is found.
In most cases the cancer cells form a tumor, also called a mass or
a lump. Some cancers, like leukemia, rarely form tumors. Instead, these cancers
involve the blood and blood-forming organs, and the cancer cells circulate
through other tissues where they grow.
This document is provided for reference purposes only and not necessarily reflect the opinion of bynaturael’s team . Train your mind to test every thought and keep on searching the final truth that satisfies the conscience inside you.
No comments:
Post a Comment