11. Which of the following pairs of amino acids would carry a negative charge on their side chain at pH 8.0?
A. Asparagine & Glutamine
B. Leucine & Glycine
C. Histidine & Lysine
D. Aspartate & Glutamate
12. In a polypeptide average mass of an amino acid residue is
A. 110 daltons
B. 118 daltons
C. 80 daltons
D. 150 daltons
13. Which pair of amino acids absorbs the most UV light at 280 nm?
A. Threonine & Histidine
B. Trp & Tyrosine
C. Cystein & Asparagine
D. Phenylalnine & Proline
14. Which of the following is a nonstandard amino acid?
A. Cysteine
B. Isoleucine
C. Hydroxyproline
D. Histidine
15. Which of the following is an essential amino acid?
A. Tryptophan
B. Methionine
C. Lysine
D. All of these