User1. Which of the following best describes the effect of 2,3-bisphosphoglycerate on the binding of oxygen to hemoglobin? A. The equilibrium dissociation constant of oxygen binding for hemoglobin is increased. B. 2,3-bisphosphoglycerate enables more oxygen to bind in the lungs at higher altitudes. C. The presence of 2,3-bisphosphoglycerate decreases the Hill coefficient. D. The binding of 2,3-bisphosphoglycerate enables heme to have decreased affinity for CO2 in the lungs, which allows more O2 to bind in the lungs. E. It has no effect on CO2 affinity, but it forces heme to adopt a state that has a higher affinity for oxygen.
2. Which statement regarding carbon monoxide binding to hemoglobin is incorrect? A. CO has a higher affinity for hemoglobin than O2. B. The binding CO to hemoglobin is a reversible reaction. C. The binding of one CO molecule to hemoglobin makes it more likely that O2 will bind at other sites in the protein. D. The distal histidine residue in hemoglobin increases the affinity of CO binding to heme. E. O2 binding competes with CO binding even when O2 partial pressures are high.
3. If the Hill coefficient is found to be equal to 1, we may infer which of the following. A. There is positive cooperativity in ligand binding. B. There are multiple ligand-binding sites. C. There is negative cooperativity in ligand binding. D. There is no cooperativity in ligand binding. E. There is only one ligand-binding site.