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Hemoglobin |
HemoglobinHemoglobin is a protein that is carried by red cells acting as a oxygen carrier.
It takes the oxygen from the lungs to the peripheral tissues to retain the feasibility of cells. They also aid in O2 scavenging in anaerobic environments. Hemoglobin is made from two similar proteins that are glued together. The hemoglobin is in solution inside the cell and is surrounded by a membrane that holds them intact.
Hemoglobin transports oxygen from the lungs or gills to the rest of the body, such as to the muscles, where it releases the oxygen load.
Low hemoglobin count result in anemia. Anemia is further classified based on the size of the red blood cells, which are the cells which contain hemoglobin in vertebrates. They are microcytic (small sized red blood cells), normocytic (normal sized red blood cells), or macrocytic (large sized red blood cells). The hemaglobin level is a typical test used for blood donation.
A comparison with the hematocrit values is made by multiplying the hemaglobin by three.
Decrease of hemoglobin, with or without an absolute decrease of red blood cells, leads to symptoms of anemia. Anemia has many different causes, although iron deficiency and its resultant iron deficiency anemia are the most common. Deficiency of iron reduces heme synthesis, red blood cells in iron deficiency anemia are hypochromic (lacks the red hemoglobin pigment) and microcytic (smaller than normal). Other types of anemia are not seen to a great extent.
During the accelerated breakdown of red blood cells (hemolysis), bilirubin causes jaundice and thereby, the hemoglobin in circulation can result in renal failure. Mutations in the globin chain are associated with sickle-cell anemia and thalassemia.
The normal hemoglobin levels are 11 to 12 g/dl in pregnancy, 12.1 to 15.1 g/dl for women, 13.8 to 17.2 g/dl for men and 11 to 16 g/dl for children. Complications or errors in metabolic pathways of heme synthesis results in a group of genetic disorders, known as the porphyrias.
Hemoglobin A slowly combines with glucose at a particular point in the molecule. The resulting molecule is termed as HbA1C. As the content of glucose in the blood increases, the percentage of Hb A that is converted into HbA1C also raises. In diabetics whose blood glucose levels are high, the percent HbA1C is also more.
The slow pace of Hb A combination with glucose, makes the fact clear that the Hb A1c percentage is an indicator of the blood glucose level averaged over a longer time (the half-life of red blood cells, is typically 50-55 days). High hemoglobin is usually due to an amplified number or anomaly of red blood cells. The causes for higher hemoglobin levels include smoking, dehydration due to diarrhea/sweating, carbon monoxide exposure, living at a high altitude, anabolic steroid use, congenital heart disease, Scarring and thickening of the lung tissue, failure of the right side of your heart, kidney disease and polycythemia vera.
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