4. Which of the following refers to particularly stable arrangements of amino acid residues in a protein that give rise to recurring patterns?
(A) Primary structure
(B) Secondary structure
(C)Tertiary structure
(D) Quaternary structure
(E) None of the above

( )10. 依據最新版「性別平等教育法」，學校接獲調查申請或檢舉時，應於___內以書面通知申請人或檢舉人是否受理；承上，若確認受理申請或檢舉後，應於___內交由所設之性別平等教育委員會調查處理。請問空格內應填 (A)十日、24 小時 (B)三日、十日 (C)二十日、三個工作日 (D)二十日、三日。

1. Which amino acid does not have a primary α-amino group? (A) glutamine (B) arginine(C)lysine (D) proline (E) glutamate

2. Which tripeptides carry a net positive charge at pH 7.0? (A) Ala-Thr-Asn (B) Gln-Val-Ser(C)Arg-Glu-Met(D) Pro-Ile-Leu (E) Leu-Lys-Gly

3. Of the 20 standard amino acids, only ______ is not optically active. The reason is that its side chain ______. (A) alanine； is a simple methyl group (B) glycine； is a hydrogen atom (C)glycine； is unbranched (D) lysine； contains only nitrogen (E) proline； forms a covalent bond with the amino group

5. All of the following are considered “weak” interactions in proteins, except: (A) hydrogen bonds. (B) hydrophobic interactions. (C)ionic bonds. (D) peptide bonds. (E) van der Waals forces.

6. Which of the following best represents the backbone arrangement of two peptide bonds? (A) Cα-N-Cα—C—Cα-N-Cα-C (B) Cα-N-C—C—N-Cα (C)C-N-Cα—Cα—C-N (D) Cα-C-N-Cα-C-N (E) Cα-Cα-C-N-Cα—Cα—C

7. Thr and/or Leu residues tend to disrupt an α helix when they occur next to each other in a protein because: (A) an amino acids like Thr is highly hydrophobic. (B) covalent interactions may occur between the Thr side chains. (C)electrostatic repulsion occurs between the Thr side chains. (D) steric hindrance occurs between the bulky Thr side chains. (E) the R group of Thr can form a hydrogen bond.

8. The tripeptide glycylarginylglutamate contains four ionizable groups with pKas of 2.1, 4.1 9.8, and 12.5. Calculate the pI for this molecule. (A) 3.1 (B) 6.4 (C)7.0 (D) 7.3 (E) 8.3

9. The quantitation of proteins due to their absorbance at ~280 nm (UV region) is due to the large absorptivity of the ______ amino acids. (A) anionic (B) dansylated (C)cleaved (D) polar (E) aromatic

10. When oxygen binds to a heme-containing protein, the two open coordination bonds of Fe2+ are occupied by: (A) one O atom and one amino acid atom. (B) one O2 molecule and one amino acid atom. (C)one O2 molecule and one heme atom. (D) two O atoms. (E) two O2 molecules.