39. Which enzyme is defective in patients with maple syrup urine disease?
(A) branched-chain a-amino acid aminotransferase
(B) branched-chain a-amino acid dehydrogenase
(C) branched-chain a-keto acid dehydrogenase
(D) branched-chain a-keto acid decarboxylase

35. Which of the following statement is wrong about alternative splicing? (A) Alternative splicing is a process that exons of a gene are differentially joined or skipped (B) Multiple protein isoforms can be encoded by a single gene during the process (C) The process can produce two or more proteins that differ in their function (D) The alternatively splicing events are often differentially regulated among individuals and populations, but not across tissues

36. Which buffer molecule does NOT carry a positive charge?(A) Tris(B) phosphate(C) imidazole(D) none of the above

37. Which of the following enzymes is NOT responsible for assimilation of ammonia?(A) glutamine amidotransferase(B) glutamate dehydrogenase(C) glutamate synthase(D) carbamoyl phosphate synthetase

38. Which symptom is a consequence of vitamin B12 deficiency?(A) anemia(B) homocysteinemia(C) neurological disorder(D) all of the above

40. 2',3'-dideoxycytidine (ddC), can serve as a drug for HIV infections because of the absence of a_____group which is required for______.(A) 2'-hydroxyl; transcription(B) 3'-hydroxyl; replicative chain elongation(C) 5'-hydroxyl; translation(D) 2'-hydroxyl; replicative chain elongation

1. 屏選孔中雀 (A) 雀 (B) 孔 (C) 選 (D) 中

2. 柳無蔭心柳成插秧 (A) 柳 (B) 蔭 (C) 插 (D) 秧

3. 天息君行子喘以自強不健 (A) 喘 (B) 健 (C) 息 (D) 君

4. 載覆舟亦運能能舟水 (A) 運 (B) 能 (C) 水 (D) 覆

5. 花明暗又一柳村樹 (A) 暗 (B) 柳 (C) 樹 (D) 一