Structure and Properties of Peptides – Section 1

1. Hydrogen bonds in a-helices are

A. more numerous than Vander Waals interactions
B. not present at Phe residues
C. analogous to the steps in a spiral staircase
D. roughly parallel to the helix axis

2. The peptide bond in proteins is

A. only found between proline residues
B. usually cis unless proline is the next amino acid
C. usually trans unless proline is the next amino acid
D. is planar because of steric hindrance

3. The molecular formula for glycine is C₂H₅O₂N. What would be the molecular formula for a linear oligomer made by linking ten glycine molecules together by condensation synthesis?

A. C₂₀H₅₀O₂₀N₁₀
B. C₂₀H₃₂O₁₁N₁₀
C. C₂₀H₄₀O₁₀N₁₀
D. C₂₀H₆₈O₂₉N₁₀

4. Which of the following is an example of tertiary structure in a protein?

A. A multimeric protein
B. An a-helix
C. A P-pleated sheet
D. A globular domain

5. The peptide, Val-Lys-Glu-Met-Ser-Trp-Arg-Ala, was digested with cyanogen bromide (CNBr) to produce:

A. Val-Lys + Glu-Met-Ser + Trp-Arg-Ala
B. Val-Lys-Glu-Met-Ser-Trp + Arg-Ala
C. Val-Lys-Glu-Met + Ser-Trp-Arg-Ala
D. Val-Lys-Glu + Met-Ser-Trp-Arg-Ala