Anemia denotes a reduction in red blood cell count, hemoglobin content, or both. Oxygen (O2) transport capacity is decreased.
Erythropoiesis (A). Blood corpuscles develop from stem cells through several cell divisions. Hemoglobin is then synthesized and the cell nucleus is extruded. Erythropoiesis is stimulated by the hormone erythropoietin (a glycoprotein), which is released from the kidneys when renal O2 tension declines.
Given an adequate production of erythropoietin, a disturbance of erythropoiesis is due to two principal causes: 1. Cell multiplication is inhibited because DNA synthesis is insufficient. This occurs in deficiencies of vitamin B12 or folic acid (macrocytic hyperchromic anemia). 2. Hemoglobin synthesis is impaired. This situation arises in iron deficiency, since Fe2+ is a constituent of hemoglobin (microcytic hypochromic anemia).
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Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...