LEUKAEMIA
DEFINITION |
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Leukaemia is cancer of the
white blood cells. Blood cells are produced in the bone marrow from
cells called stem cells or blast cells. Bone marrow is found in the
long bones of the limbs (although the amount decreases with age), in
the skull, vertebrae, pelvis and chest bone (sternum).
Production of blood cells
Blast cells differentiate (mature and become specialised) to form
the different types of blood cells, i.e. red blood cells, white
blood cells and platelets. Mature cells are then released into the
circulation.
Red blood cells
carry oxygen around the body to all the organs and tissues. White
blood cells fight infection. There are several types of white blood
cell including:
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Granulocytes: There are three types of
granulocytes - neutrophils, eosinophils and basophils. They all
have granules in their cytoplasm (fluid inside the cell). The
granules contain enzymes and chemicals that help the cells to
fight infection. Eosinophils and basophils also play a role in
allergic reactions. |
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Monocytes: These remove foreign material, including bacteria,
from the blood. They have a role in the body's immune response. |
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Lymphocytes: There are two main types of lymphocyte - T cells
and B cells. These are the main cells of the immune system. B
cells are responsible for antibody production. T cells recognise
and attack cells that have been infected by viruses. Once they
leave the bone marrow, these cells mature further in the lymph
tissue, e.g. lymph nodes and thymus. |
Platelets play an
important role in clot formation. |
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| LEUKAEMIA RELATED ITEMS |
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