31. The α-amino acids have a carboxyl group with a pK around __________ , and an amino group with a pK near __________ .
A. 1.1, and 12.1
B. 6.5, and 8.0
C. 3.3, and 10.5
D. 2.2, and 9.4
32. Coomassie Blue stains the proteins by reacting with
A. arginine residues
B. free c-termini
C. peptide bonds
D. aromatic ring
33. Which amino acid when exposed to ninhydrin produces a brown color?
A. Asparagine
B. Proline
C. Alanine
D. Valine