Platelets are components of blood produced in bone marrow. They are critical to blood clotting during what is called primary hemostasis -- the clotting that takes place immediately after an event that damages a blood vessel.
When the body's platelet count is depleted, severe bruising or uncontrolled bleeding can occur. Excessive bleeding and bruising can lead to anemia (a low red blood cell count), and if left untreated, death can result.
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