by Garrett Grisham
When oxygen binds to heme, the oxygen forms a hydrogen bond with ___ - answer-His E7
In the ___ state of hemoglobin, the iron ion is out of the plane of the porphyrin ring - answer-T
The conversion of hemoglobin from the T to the R state requires breaking of ___ involving C-
terminal residues - answer-ion pairs
Hemoglobin's subunits bind oxygen in a ___ manner - answer-Positively cooperative
An increase in pCO2 causes hemoglobin's affinity for oxygen to ___ - answer-decrease
The absence of 2,3-BPG causes hemoglobin's affinity for oxygen to______ - answer-increase
The ______ model of allosterism requires subunits to change conformation simultaneously -
answer-Symmetry
Sickle cell hemoglobin does not form fibers in the ______ form - answer-R
When unstable hemoglobin is degraded; degradation products often cause cell lysis, leading to
a condition called ______. - answer-Hemolytic Anemia
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, Mutations that favor the oxidation of the heme iron(II) to iron(III) can cause ______ - answer-
Cyanosis
Which of the following is not a ligand to the porphyrin ring Fe(II) ion in oxymyoglobin?
A) His E7
B) His F8
C) Nitrogen atoms in the porphyrin ring
D) Oxygen
E) all are ligands - answer-A) His E7
Which gas does not bind to the porphyrin ring Fe(II) ion in myoglobin?
A) NO
B) CO
C) CO2
D) O2
E) H2S - answer-C) CO2
Which of the following statements does not apply to the K value in the equation for the oxygen
binding curve of myoglobin?
A) It is numerically equal to p50.
B) It is defined as that oxygen partial pressure at which half of the oxygen binding sites are
occupied.
C) It is a measure of the affinity of myoglobin for oxygen.
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