ALLOSTERIC EFFECTS QUIZ

100-fold lower affinity for the last O2 bound than for the first

extensive protein conformational change

both (a) and (b)

100-fold higher affinity for the last O2 bound than for the first

both (b) and (c)

show a Hill coefficient (nH) of 0.0

show a Hill coefficient (nH) of n

only be found in either the unliganded form or the fully liganded form

to maximize oxygen delivery to the tissues

only in humans

for maintaining Fe in the Fe2+ state

to minimize oxygen delivery to the tissues

2.8 and 1.0

1.2 and 4.5

1.0 and 2.8

4.5 and 1.2

a linear Scatchard Plot

a sigmodial binding curve

both (b) and (c)

a hyperbolic binding curve

it is displaced from the heme by movement of the proximal histidine

BPG binds to the R state with the same affinity as the T state

its binding pocket becomes too small to accommodate BPG

it is displaced from the heme by oxygen

the absence of competing ligands

the presence of hydrating water molecules

the amino acid residues lining the binding site

the opposite chirality of the binding ligand

not defined

None of these

1

2

increases the binding affinity

both (a) and (c)

stabilizes the R state of the protein

decreases the binding affinity

movement of the proximal histidine towards the heme

binding of oxygen to the heme

reorganization of protein-protein contacts between the individual subunits

movement of the F-helix, which contains the proximal His