Arginine has a ________ group

Guanidino (A really strong base/ very high pKa)

Lysine has an _______ group

Amine

Histidine has an _______ group

Imidazole (Deprotonation occurs at a very low pH)

Can Zwitterions Act as Acids or Bases?

Yes they can

Which Amino Acids are ionizable?

Aspartate, Arginine, Tyrosine, Histidine, Glutamate, Cysteine, and Lysine

How do you calculate the Isoelectric point?

We need to find the pK values on either side of the Zwitterion. First, draw out all the ionizable amino acids. Then, write out their pKa values and rank them from 1 to however many. Then as you move through the number line of charges, note down which pKa takes the charge to 0 and from 0. Add those two values together and divide by 2 to find the isoelectric group.