When oxygen is bound to myoglobin, the amino acid _____ is complexed to the iron ion of the heme group while _______ forms a hydrogen bound to the oxygen.
A)cysteine; serine
B)cysteine; histidine
C)serine; cysteine
D)histidine; histidine
E)histidine; cysteine

Question

Quizplus · Accepted Answer

Histidine is the amino acid that complexes to the iron ion in the heme group of myoglobin, and another histidine residue forms a hydrogen bond with the bound oxygen. This dual role of histidine is crucial for the function of myoglobin in oxygen binding and release.

When Oxygen Is Bound to Myoglobin, the Amino Acid _____