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2. Red blood cells (also called
erythrocytes) give blood it's red color, but more importantly, carry oxygen from the lungs
to the rest of the body and return carbon dioxide to the lungs as waste.
3. Platelets (also called thrombocytes)
help the body form blood clots to control bleeding.
4. In addition to these three cell types,
the blood also contains a fluid called plasma.
All of these products are formed in the
bone marrow, a spongy area located in the center of bones. Larger bones have more bone
marrow, and therefore produce more cells. The larger bones include the femur (top part of
the leg), the hip bones, and parts of the rib cage. The bone marrow contains a small
percentage of cells that are in development and are not yet mature.
These cells are called blasts. Once the
cell has matured, it moves out of the bone marrow and into the circulating blood. The body
has mechanisms to know when more cells are needed and has the ability to produce them in
an orderly fashion.In the case of leukemia, one blood cell goes awry (in the majority of
cases this cell is a white blood cell) and the body produces large numbers of this cell.
When looked at under a microscope, these abnormally produced cells look different then the
healthy cells and do not function properly. The body continues to produce these abnormal,
non-functional cells, leaving little space for healthy cells. This imbalance of healthy
and unhealthy cells is what causes the symptoms of leukemia.
OR
Leukemia
is cancer of the blood cells. Normally, the blood produces new cells as needed and as
others die off. With leukemia, however, new and functionless cells form and replicate at
an uncontrollable rate, overloading the body. Although it begins in the bone marrow,
leukemia quickly spreads to the blood and eventually to the lymph nodes, spleen, brain,
spinal cord, spinal fluid, and other organs. What sets leukemia apart is that most other
forms of cancers start in bodily organs and spread to, not from, the bone marrow.
What are the
different types of leukemia?
The four major
types of leukemia are:
· acute myeloid leukemia
· acute lymphocytic leukemia
· chronic myeloid leukemia
· chronic lymphocytic leukemia
All leukemias are classified as either acute or chronic. Because blood cells can no longer
carry out their tasks, acute leukemia worsens quickly. Conversely, people with chronic
leukemia may experience relatively few symptoms early on in the disease, but the disease
progresses more rapidly as the number of leukemia cells increases.
What is
acute myeloid leukemia?
Acute myeloid
leukemia is marked by the uncontrolled growth of dysfunctional cells in the bone marrow
and the deficiency of red blood cells, platelets, and white blood cells-the latter of
which is caused by the ceased production of normal bone marrow cells. The decrease in
healthy red blood cells often causes anemia, while the drop in functional white blood
cells and platelets impairs the body's ability to fight infection. Acute myeloid leukemia
affects both children and adults.
What is
chronic myeloid leukemia?
Chronic myeloid
leukemia is very similar to acute myeloid leukemia, except that it does not typically
affect children and it develops at a much slower rate. The disease is caused by the
presence of too many underdeveloped white blood cells (called lymphoblasts) in the blood
or bone marrow.
What is
acute lymphocytic leukemia?
Acute
lymphocytic leukemia is a rapidly progressing disease that is marked by the overabundance
of immature or functionless white blood cells (called lymphoblasts) in the blood and bone
marrow. Although it is also found in adults, this is the most common type of leukemia to
strike children.
What is
chronic lymphocytic leukemia?
Chronic
lymphocytic leukemia is caused by the overbundance of mature white blood cells
(lymphocytes) in the body. The disease, which begins in the bone marrow but quickly
spreads to other organs, rarely affects children and instead typically strikes adults over
age 55.
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