a. Write out the reaction equilibria for the sequential deprotonation of tyrosine and the equations for the corresponding Ka for each. (Hint: There should be three reaction equilibria.) You may abbreviate tyrosine as Tyr and indicate the appropriate number of hydrogens and charge (i.e., H3Tyr+ for fully protonated tyrosine). Also make sure you differentiate between the different Kas (Ka’, Ka”, etc). b. Draw out the full structures of tyrosine and indicate the order in which the hydrogens come off. c. On one graph, plot the fractional composition of each protonated/deprotonated form of tyrosine in aqueous solution as a function of pH. Note that the conjugated pairs are at equal concentration when the pH is equal to the pKa of the acid member of the pair. (See Table 8.6 of your book for pKa values.) Indicate pI on the graph d. What equation relates the pI of tyrosine to its pKas? e. Clearly indicate the pI on your graph in question 4b).