Chapter 7, Problem 4E

Summary Introduction

To calculate: The p₅₀ value for hemoglobin if Y = 0.82 when pO2 = 25 torr.

Concept introduction: The fractional saturation is the partial fulfillment of the allosteric sites of the protein by the ligand. The ligand in hemoglobin is oxygen. The fractional saturation (Y) is the fraction at which the protein molecules are saturated with the ligand. At Y_50, half the protein molecules are bound to ligand and half to proteins, and ligands are free, thus the equilibrium is achieved. The concentration of gas is mentioned as partial pressure. Torr is the unit of measure for pressure.