Medical Books and Lectures notes - Free downloads

1-  What is the reason of sickle cell anemia? A.         substitution of Val with Glu in beta-chain of hemoglobin B.       substitution of Lent with ILe in beta-chain of hemoglobin C.          substitution of Glu with Val in beta-chain of hemoglobin D.         substitution of Phe with Gln in beta-chain of hemoglobin 2- what is not correct answer for hemoglobin and myoglobin ? A.       myoglobin has low affinity to oxygen than hemoglobin B.       myoglobin has one site to bind oxygen C.       Low pH decrece the affinity of hemoglobin to oxygen D.       myoglobin  has one polipeptide chain 3- alanin is similar to serine in the same way that ? A.       Val is similar to thr B.       Phe is similar to tyr C.       Phe is similar to trp D.       Ser is similar to thr 4- Which one describes an allosteric interaction between a ligand and a protein? A.       binding of a molecule to a binding site affects binding of additional molecules to the same site