To measure the effective affinity of a protein target for an inhibitor (K₁), one does NOT need to know the equilibrium dissociation constant (KD) for the protein's native substrate. TRUE FALSE To measure the equilibrium binding constant (KD) of a protein-ligand interaction using Scatchard analysis, one needs to have an accurate estimate of the total protein concentration in the binding reaction. TRUE FALSE The statin drug, atorvastatin (Lipator), binds to the HMG-COA reductase with greater affinity than the natural substrate HMG-CoA, due to the presence of a bulky hydrophilic group on the drug that makes polar contacts near the enzyme active site. TRUE FALSE The 'induced fit' model for protein-ligand interactions suggests that proteins are rigid and can NOT undergo conformational changes upon ligand binding. TRUE FALSE