Oxygen-binding curve hemoglobin

We can determine quantitatively the physiological significance of the sigmoid nature of the hemoglobin oxygen-binding curve, or, in other words, the biological importance of cooperativity. The equation... 

Two quite different models were proposed about 25 years ago to explain the unusual nature of the hemoglobin oxygen-binding curve (fig. 5.14). These models can also be used as a starting point for discussing other allosteric proteins. The first model, introduced by Jacque Monod, Jeffery Wyman, and Pierre Changeux in 1965, is called the symme-... 

Fig. 1.1. (a) Fraction of occupied oxygen binding sites in hemoglobin and in a separated subunit as a function of partial oxygen pressure. The hemoglobin oxygen binding curve is... 

The qualitative relationship between the oxygen binding curves for hemoglobin and myoglobin. 

Thus, for hemoglobin (Hb) the oxygen binding curves are sigmoidal as is shown in the above figure. The fact that n exceeds the unit can be ascribed physically to the fact that attachment of O2 to one heme group... 

Figure 10.1 The oxygen-binding curves of (a) myoglobin and (b) hemoglobin.

Hemoglobin has been a favorite protein molecule for designing and testing various models of the molecular basis of subunit interactions in multisubunit proteins. In the 1960s, two mechanisms were advanced to account for the sigmoidal nature of the oxygen binding curve for Hb A, one proposed by Monod et al. (1965) based on a... 

The oxygen binding curve for hemoglobin is shown in Figure 1-12. In the presence of CO2, the partial pressure of 02 required for any given fraction of... 

Figure 7.9 Responding to exercise. The drop in oxygen concentration from 40 torr in resting tissues to 20 torr in exercising tissues corresponds to the steepest part of its oxygen-binding curve. Consequently, hemoglobin is very effective in providing oxygen to exercising tissues.

Figure 7.29 Oxygen-binding curves for several Hill coefficients. The curve labeled n = 2,8 closely resembles the curve for hemoglobin.

Oxygen binding curves of myoglobin and hemoglobin. Note the reduced hemoglobin saturation at low oxygen pressure that allows better delivery of oxygen to peripheral tissues. 

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