ALLOSTERIC EFFECTS QUIZ

increasing [H+] and decreasing Hb affinity for O2

decreasing Hb affinity for O2

increasing [H+]

increasing Hb affinity for O2

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

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

extensive protein conformational change

both (a) and (b)

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

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

it is displaced from the heme by oxygen

its binding pocket becomes too small to accommodate BPG

2.8 and 1.0

4.5 and 1.2

1.0 and 2.8

1.2 and 4.5

decreases the binding affinity

stabilizes the R state of the protein

increases the binding affinity

both (a) and (c)

only in humans

to maximize oxygen delivery to the tissues

for maintaining Fe in the Fe2+ state

to minimize oxygen delivery to the tissues

binding of oxygen to the heme

movement of the proximal histidine towards the heme

reorganization of protein-protein contacts between the individual subunits

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

both (b) and (c)

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

show a Hill coefficient (nH) of n

show a Hill coefficient (nH) of 0.0

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

2

1

not defined

None of these