Which of the following hemoglobin subunits is responsible for the initial binding of oxygen to the hemoglobin molecule?

A Alpha subunit ✓
B Beta subunit
C Gamma subunit
D Delta subunit

Explanation

The alpha subunit of hemoglobin is responsible for the initial binding of oxygen, which then facilitates the binding of oxygen to the other subunits.

Source

Biochemistry textbooks by Stryer or Berg
Hematology Hematology: Hemoglobin and Oxygen Transport Hematology: Hemoglobin and Oxygen Transport Hard MEDICAL Confidence: high