5. Which of the following is incorrect to describe myoglobin (Mb) and hemoglobin (Hb)? (A) The R-form and T-form of the Hb differ at their salt bridges, H-bonds and covalent linkages between subunits (B) Oxygen binding curve of Hb becomes closer to that of Mb in the absence of CO2 and BPG. (C) Oxygen binds to a ferrous ion of the heme in both proteins. (D) At low pH values, the population of R-form is less than the T-from of Hb. (E) Hb can carry CO2 but at different site from the one that binds CO and O2.