1. The torsion angles which describe the protein backbone are: a) Alpha, beta, gamma b) Phi, psi, omega c) Phi, psi, omega, chi
2. The phi angle is defined by the atoms a) C-N-CA-C b) CA-C-N-CA c) N-CA-C-N
3. The psi angle is defined by the atoms a) C-N-CA-C b) CA-C-N-CA c) N-CA-C-N
4. The omega angle is defined by the atoms a) C-N-CA-C b) CA-C-N-CA c) N-CA-C-N
5. The peptide bond is: a) A single bond b) A double bond c) A partial double bond
6. The nature of the peptide bond results from: a) Delocalization of a lone pair of electrons on the carbonyl oxygen resulting in a partial positive charge on the oxygen and a partial negative charge on the backbone nitrogen b) Delocalization of a lone pair of electrons on the backbone nitrogen resulting in a partial positive charge on the nitrogen and a partial negative charge on the carbonyl oxygen
7. The peptide bond is always: a) Close to +/- 90 degrees b) Close to 90 degrees c) Close to 180 degrees d) Close to 0 degrees e) Freely rotatable f) None of the above
8. Which direction corresponds to a positive torsion angle? a) Moving the near atom anti-clockwise or the distant atom clockwise b) Moving the near atom clockwise or the distant atom anti-clockwise
9. The peptide bond is often close to 0 degrees when the following amino acid is: a) Glycine b) Proline c) Alanine d) Tryptophan