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This is a three-part question about a tripeptide. Answer all three sub- questions. The pKR of side chains of Tyr, and Lys is 10.46 and 10.54 respectively. The molecular weight of amino acids Ala, Lys, and Tyr in neutral form is 89.1, 146.2, and 181.2 Da, respectively. 1) Draw the chemical structure of the dominant form of tripeptide AKY at pH = 11.5, ensure you have the correct stereochemistry and ionization state of each functional group (Hint, lysine has a C-epsilon as the furthest carbon from C-alpha). (6 Marks) 2) Calculate the pl of tripeptide AKY, assuming the terminal amino group has a pka of 8.0, and the terminal carboxyl group has a pKa of 3.5 (3 marks) 3) Calculate the molecular weight of AKY at pl (2 marks)