Degradation in Vertebrate Animals
When red cells reach the end of their life due to aging or defects, they are broken down in spleen, the hemoglobin molecule is broken up and the iron gets recycled. This process also produces one molecule of carbon monoxide for every molecule of heme degraded. This is one of the few natural sources of carbon monoxide production in the human body, and is responsible for the normal blood levels of carbon monoxide even in people breathing pure air. The other major final product of heme degradation is bilirubin. Increased levels of this chemical are detected in the blood if red cells are being destroyed more rapidly than usual. Improperly degraded hemoglobin protein or hemoglobin that has been released from the blood cells too rapidly can clog small blood vessels, especially the delicate blood filtering vessels of the kidneys, causing kidney damage. Iron is removed from heme and salvaged for later use, it is stored as hemosiderin or ferritin in tissues and transported in plasma by beta globulins as transferins. When the porphyrin ring is broken up, the fragments are normally secreted as a yellow pigment called bilirubin, which is secreted into the intestines as bile. Intestines metabolise bilirubin into urobilinogen. Urobilinogen leaves the body in faeces, in a pigment called stercobilin. Globulin is metabolised into amino acids which are then released into circulation.
Read more about this topic: Hemoglobin
Famous quotes containing the words degradation and/or animals:
“Why, since man and woman were created for each other, had He made their desires so dissimilar? Why should one class of women be able to dwell in luxurious seclusion from the trials of life, while another class performed their loathsome tasks? Surely His wisdom had not decreed that one set of women should live in degradation and in the end should perish that others might live in security, preserve their frappeed chastity, and in the end be saved.”
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