Which of the Following Statements About the Binding of Oxygen

question 32

Multiple Choice

Which of the following statements about the binding of oxygen to deoxyhemoglobin is correct

• A) The binding of oxygen to Fe²⁺ in the first heme pulls the iron ion into the porphyrin ring, decreasing the affinity for the second oxygen.
• B) The binding of oxygen to Fe²⁺ in the first heme pushes the iron ion out of the porphyrin ring, decreasing the affinity for the second oxygen.
• C) The binding of oxygen to Fe²⁺ in the first heme pulls the iron ion into the porphyrin ring, increasing the affinity for the second oxygen.
• D) The binding of oxygen to Fe²⁺ in the first heme pushes the iron ion out of the porphyrin ring, increasing the affinity for the second oxygen.
• E) Oxygen does not bind to deoxyhemoglobin.