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Hemoglobin

APCHEM-GG8QEV

Created for Albert.io. Copyright 2016. All rights reserved.

Adult hemoglobin (Hb) and fetus hemoglobin (HbF) molecules have slightly different properties, but both are in equilibrium with oxygen as seen in the chemical equations above.

A fetus maintains its own circulatory system, independent of its mother’s blood, and cannot breathe in any air in the womb to obtain oxygen. A fetus obtains oxygen from its mother's hemoglobin when fetal blood flows in close proximity to the mother's blood in the placenta.

Which of the following is the BEST explanation for the data presented in the graph above?

A

The equilibrium constant for Hb is larger than HbF; thus, the reaction is reactant-favored, and Hb loads oxygen at a higher oxygen concentration.

B

The equilibrium constant for HbF is larger than Hb; thus, the reaction is product-favored, and HbF loads oxygen at a lower oxygen concentration.

C

The equilibrium constant for Hb is larger than HbF; thus, the reaction is product-favored, and Hb loads oxygen at a higher oxygen concentration.

D

The equilibrium constant for HbF is larger than Hb; thus, the reaction is reactant-favored, and HbF loads oxygen at a lower oxygen concentration.