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12 臨床上為病患測量脈搏時,下列何種狀況會使病患出現心搏過慢的情形? (A)甲狀腺功能亢進 (B)嚴重貧血 (C)缺氧 (D)顱內壓升高

39. A researcher subjects four distinct biological structures (a functional globular protein, a segment of DNA, a cellulose fiber, anda molecule of amylopectin) to an environment where all non-covalent interactions (hydrogen bonds, ionic bonds, van der Waals forces, and hydrophobic interactions) are completely disrupted, but all covalent bonds (peptide bonds, glycosidic linkages, and phosphodiester linkages) remain intact. Which resulting observation is the LEAST accurate regarding the stable molecular components remaining after this treatment? (A) The globular protein, such as transthyretin, would be converted into a nonfunctional, linear polypeptide chain, retaining its unique amino acid sequence. (B) The secondary structure elements (such as a-helices and β-pleated sheets) within the polypeptide backbone of the globular protein would no longer exist. (C) The two complementary strands of the DNA double helix would separate entirely, resulting in two distinct, single polynucleotide strands. (D) The amylopectin molecule (a storage polysaccharide) would be cleaved into hundreds of individual glucose monomers. (E) A cellulose molecule would retain its straight, unbranched configuration, although it would no longer be grouped into strong microfibrils.

42. Pepsin is a digestive enzyme that functions optimally at a pH of 2, an environment highly concentrated with H* ions. In contrast, most enzymes found in the human body have optimal pH values ranging from 6 to 8. The extreme acidity of pH 2 would typically cause most enzymes to denature, leading to a sharp drop in activity, because the high concentration of H+ ions disrupts the weak interactions crucial for stabilizing the protein's functional shape. Which statement below best describes the mechanism by which Pepsin is specifically adapted to maintain its maximum catalytic activity in the stomach environment? (A) Pepsin uses strong covalent bonds (peptide bonds) to form its active site, which cannot be broken by H+ ions, unlike the weak bonds found in other enzyme active sites. (B) Pepsin's △G (Free Energy change) for its specific catabolic reaction shifts to a highly negative value at pH 2, thereby increasing the spontaneous rate of the reaction independent of structure. (C) The structure of Pepsin minimizes the use of the most electronegative elements. (Oxygen and Nitrogen) in its regulatory sites, making it insensitive to competitive inhibition by H+ ions. (D) Pepsin has evolved to significantly raise the overall activation energy (EA) barrier of its substrate at neutral pH, forcing the reaction to only proceed effectively when thermal energy is supplied by the acidic environment. (E) The amino acid sequence of Pepsin results in a unique three-dimensional configuration that prevents the high concentration of H+ ions from disrupting the crucial weak interactions (such as ionic bonds and hydrogen bonds) necessary for its active shape.

22.有關文中歸有光提及兒子之事,下列敘述何者正確? (A)兒子住在此處七年,父子之情深厚 (B)十二月八日為兒子獨自離家的時間 (C)明確交代兒子確切死因及死亡地點 (D)兒子生前喜與弟弟於思子亭中嬉戲

12. X1 年間,乙公司在長期投資方面發生下列事項: 4 月 6 日:以每股$3.25 購入丙公司股票 2,000 股,另支付$500 手續費。 7 月 7 日:收到丙公司發放的現金股利,每股$0.70。 12 月 31 日:丙公司報導本年度淨利為$50,000。丙公司共有 8,000 股普通股流通在外。 請問截至 X1 年 12 月 31 日,「採權益法之投資-丙公司股票」帳戶餘額應為多少? (A)$17,600 (B)$18,100 (C)$19,500 (D)$20,900