Sickle cell anemia is an inherited blood disorder characterized by defective hemoglobin. It affects millions of people throughout the world and approximately 72,000 people in the US. It is present in 1 in every 500 African-American births. Sickle cell anemia is an inherited disord

er in which an abnormality occurs in the structure of hemoglobin. The disorder arises from a mutated gene for beta-globin, one of two kinds of polypeptide chains in the hemoglobin molecule. Hemoglobin is a substance found within red blood cells that is necessary for carrying oxygen. The chemical structure is known as hemoglobin A. Humans depend on the intake of oxygen for aerobic respiration. Oxygen in air flows into the lungs, then diffuses into the blood. There it binds to hemoglobin, which transport it through arteries, arterioles, and then capillaries threading past all living cells in the body. A steep oxygen concentration gradient exists between blood and the fluid within the surrounding tissues, so most of the oxygen diffuses into the tissues and into cells. With this extensive cellular uptake, the concentration of oxygen in blood declines. The abnormally formed hemoglobin allele is called hemoglobin S, or sickle hemoglobin. In the red blood cells of p

Some topics in this essay:
, blood cells, red blood cells, red blood, sickle cell, white blood cells, hemolytic anemia, white blood, carry carbon dioxide, oxygen carry carbon, cell anemia inherited, deliver oxygen, 2 red, oxygen carry, carry carbon, anemia inherited,