To become bound to hemoglobin for transport in a mammal, ...

[luvbio]

To become bound to hemoglobin for transport in a mammal, atmospheric molecules of oxygen must cross
A)  zero membranesoxygen binds directly to hemoglobin, a protein dissolved in the plasma of the blood.
B)  one membranethat of the lining in the lungsand then bind directly to hemoglobin, a protein dissolved in the plasma of the blood.
C)  two membranesin and out of the cell lining the lungand then bind directly to hemoglobin, a protein dissolved in the plasma of the blood.
D)  four membranesin and out of the cell lining the lung, in and out of the endothelial cell lining the pulmonary capillary–and then bind directly to hemoglobin, a protein dissolved in the plasma of the blood.
E)  five membranesin and out of the cell lining the lung, in and out of the endothelial cell lining the pulmonary capillary, and into the red blood cellto bind with hemoglobin

[coco]

Choose E

GL