1. What explains the slight differences in the relative mobility of the polar amino acids SER and THR?

2. Despite its ring, HIS is listed with the basic amino acids. Does its mobility in our TLC system support this? How so?

3. Why is PROs reaction with ninhydrin very different from the other amino acids? (compare the structure of PRO to any of the other protein amino acids)

4. Cysteine is Serine with an S replacing the O. Why is Cys more mobile than Ser in this solvent system? (compare the electronegativitys of O and S).

5. Finally, evaluate the aspartame lane. What two amino acids make up Aspartame (aka NutraSweet)?_____________________________n