Carbon monoxide oxyhemoglobin

Unfortunately, hemoglobin forms a complex with carbon monoxide that is considerably more stable than oxyhemoglobin. The equilibrium constant for the reaction... 

C20-0111. Oxyhemoglobin is bright red, but deoxyhemoglobin is blue. In both cases the iron is in the +2 oxidation state. Give a detailed explanation for the difference in color. How would you test your hypothesis Based on your explanation, what color would you predict for a sample of blood that is saturated with carbon monoxide ... 

These symptoms are caused by carbon monoxide s chemical properties, specifically its tendency to bond to hemoglobin in the blood. Hemoglobin is a protein found in red blood cells that transports oxygen from the lungs to cells. It contains an iron atom located at the center of the molecule to which oxygen bonds to form the complex known as oxyhemoglobin ... 

The bond between iron and carbon monoxide, however, is at least 300 times stronger than that between iron and oxygen. When carbon monoxide is present in the lungs, therefore, it displaces oxygen from oxyhemoglobin, forming carboxyhemoglobin instead ... 

PROBLEM 19.6 The equilibrium between oxyhemoglobin and carboxyhemoglo-bin suggests an approach to treating mild cases of carbon monoxide poisoning. Explain. 

Carbon monoxide enters the bloodstream through the lungs and reacts with oxyhemoglobin (02Hb) to produce carboxyhemoglobin (COHb) ... 

Carbon monoxide hemoglobin Oxyhemoglobin High-density lipoprotein Histidine... 

Carbon monoxide causes toxicity by binding reversibly to the hemoglobin molecule, forming COHb, which decreases the oxygen-carrying capacity of the blood. This capacity is further reduced because the presence of COHb alters the dissociation of oxyhemoglobin in the tissues. 

Hb-CO - hemoglobin-carbon monoxide compound, the compound formed by CO and blood hemoglobin, whereby the oxygen (Hb-02, oxyhemoglobin) becomes displaced. 

As mentioned previously, CO competes with 02 for binding of hemoglobin, but, in addition, it also binds other proteins such as myoglobin, cytochrome c oxidase, and cytochrome P-450. Carbon monoxide also impairs the facilitated diffusion of 02 to the mitochondria, shifting the oxyhemoglobin dissociation curve to the left. Alteration of oxyhemoglobin dissociation curve by COHb occurs in such a manner that 02 is released to tissues with great difficulty and at a lower 02 tension. 

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