Myoglobin and hemoglobin Flashcards
When oxygen binds to a heme-containing protein, the two open coordination bonds of Fe2+ are occupied by:
Select one:
a. two O2 molecules.
b. two O atoms.
c. one O2 molecule and one heme atom.
d. one O2 molecule and one amino acid atom.
e. one O atom and one amino acid atom.
d. one O2 molecule and one amino acid atom.
In the binding of oxygen to myoglobin, the relationship between the concentration of oxygen and the fraction of binding sites occupied can best be described as:
Select one:
a. random.
b. sigmoidal.
c. linear with a positive slope.
d. linear with a negative slope.
e. hyperbolic.
e. hyperbolic
Myoglobin and the subunits of hemoglobin have:
Select one:
a. no obvious structural relationship.
b. very similar primary structures, but different tertiary structures.
c. very similar primary and tertiary structures.
d. very different primary and tertiary structures.
e. very similar tertiary structures, but different primary structures.
b. very similar tertiary structures, but different primary structures.
In hemoglobin, the transition from T state to R state (low to high affinity) is triggered by:
Select one:
a. subunit dissociation.
b. oxygen binding.
c. Fe2+ binding.
d. heme binding.
e. subunit association.
b. oxygen binding
Which of the following is not correct concerning 2,3-bisphosphoglycerate (BPG)?
Select one:
a. It is normally found associated with the hemoglobin molecules that are extracted from red blood cells.
b. It decreases the affinity of hemoglobin for oxygen.
c. It binds to the heme groups of hemoglobin.
d. It is an allosteric modulator.
e. It binds with lower affinity to fetal hemoglobin than to adult hemoglobin.
It binds to the heme groups of hemoglobin.
The amino acid substitution of Val for Glu in Hemoglobin S results in aggregation of the protein. Which interactions are formed between the molecules in this case?
Select one:
a. hydrophobic
b. ionic
c. hydrogen bonding
d. covalent
e. disulfide
a. hydrophobic
