Hemoglobin system

Would you expect the blood-hemoglobin system to transport more moles of 02 or C02 Why ... 

The blood, for example, is protected by two important buffer systems the hemoglobin system and the bicarbonate system, which stabilize its pH between 7.37 and 7.43. The bicarbonate system is the most important buffer for plasma and interstitial fluids. Neutralizing the skin with sodium bicarbonate is the most natural method. 

Adair, G.S. 1925. The hemoglobin system. VI. The oxygen dissociation curve of hemoglobin. J. Biol. Chem. 63 529-45. 

Giardina, B., Corda, M., Pellegrini, M.G. Condo, S.G. Brunori, M. (1985). Functional properties of the hemoglobin system of two diving birds (Podiceps nigricollis and Phalacrocorax carbosinensis). Mol. Physiol, 7, 281-92. 

G. S. Adair, The Hemoglobin System. VI. The Oxygen Dissociation Curve of Hemoglobin. J. Biol Chem., 63,529-545,1925. 

Ulanowlcz, R.E, and G.C, Frazier. "The transport of oxygen and carbon dioxide In hemoglobin systems." Mathematical Blosclences 1 (1970) 111-129. 

Molecular Adaptation in Physiological Requirements The Hemoglobin System of Trout... 

The oxygen-hemoglobin system is but one of many examples of adsorption processes that occur in the human body. These are often irreversible in nature (i.e., involve chemisorption) and do not properly fall into the category of phase equilibria. All such events, however, do involve the transport of mass in one form or another, with both membranes and fluid barriers defining the mass transfer resistance. We will return to this topic in Section 8.2 dealing with membrane separation processes. 

In other words, repression may vary in its embryologic depth. For example, repression of the fetal hemoglobin system which takes place not long before birth is superficial repression of late type. In the same stem cells of the erythroid series ability to synthesize collagen or antibodies, for example, is repressed more and earlier. Syntheses characteristic of, for example,... 

A proposal will be made here that in some specific cases the GAE represents a suitable way for the study of the structure-function relationship in the hemoglobin system. Before proceeding to put forward this proposal a short critical account on the modeling usually used in discussions relating the structure and function of this system will be presented. 

Zal, F., Lallier, F.H., Wall, J.S., Vinogradov, S.N., and Toulmond, A. (1996a) The multi-hemoglobin system of the hydrothermal vent tube worm Riftia pachyptila 1. Reexamination of the number and masses of its constituents./. Biol Chem., 271,8869-8874. 

A system of internal iron exchange exists which is dominated by the iron required for hemoglobin synthesis. For formation of red blood cells, iron stores can furnish 10—40 mg/d of iron, as compared to 1—3 mg from dietary sources (74). Only ca 10 wt % of ingested iron actually is absorbed. 

The half life for NO in cellular systems ranges from 5—30 seconds. Superoxide, hemoglobin, and other radical trapping agents remove NO after it has been formed. 

Fig. 3. Schematic diagram of a dark field system for measuriag the light scatteriag by a spherical red blood cell where V = volume of sample and HC = hemoglobin concentration. Optical flow cell system having double-angular interval detection at angles 9 and 02.

The automated method differs from the ICSH method chiefly in that oxidation and ligation of heme iron occur after the hemes have been released from globin. Therefore, ferricyanide and cyanide need not diffuse into the hemoglobin and methemoglobin, respectively. Because diffusion is rate-limiting in this reaction sequence, the overall reaction time is reduced from approximately three minutes for the manual method to 3 —15 seconds for the automated method. Reaction sequences in the Coulter S + II and the Technicon H 1 and H 2 are similar. Moreover, similar reactions are used in the other Coulter systems and in the TOA and Unipath instmments. 

The second example of an air pollutant that affects the total body burden is carbon monoxide (CO). In addihon to CO in ambient air, there are other sources for inhalation. People who smoke have an elevated CO body burden compared to nonsmokers. Individuals indoors may be exposed to elevated levels of CO from incomplete combustion in heating or cooking stoves. CO gas enters the human body by inhalation and is absorbed directly into the bloodstream the total body burden resides in the circulatory system. The human body also produces CO by breakdown of hemoglobin. Hemoglobin breakdown gives every individual a baseline level of CO in the circulatory system. As the result of these factors, the body burden can fluctuate over a time scale of hours. 

The most conspicuous use of iron in biological systems is in our blood, where the erythrocytes are filled with the oxygen-binding protein hemoglobin. The red color of blood is due to the iron atom bound to the heme group in hemoglobin. Similar heme-bound iron atoms are present in a number of proteins involved in electron-transfer reactions, notably cytochromes. A chemically more sophisticated use of iron is found in an enzyme, ribo nucleotide reductase, that catalyzes the conversion of ribonucleotides to deoxyribonucleotides, an important step in the synthesis of the building blocks of DNA. 

For many years hemoglobin was the only allosteric protein whose stereochemical mechanism was understood in detail. However, more recently detailed structural information has been obtained for both the R and the T states of several enzymes as well as one genetic repressor system, the trp-repressor, described in Chapter 8. We will here examine the structural differences between the R and the T states of a key enzyme in the glycolytic pathway, phosphofructokinase. 

D. Agents which act on the blood or hematopoietic system Decreases hemoglobin function deprive body tissues of oxygen ... 

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