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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

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.

43. During the mitotic phase, the enzyme separase is responsible for cleaving the cohesin proteins that hold sister chromatids together, a step crucial for the initiation of anaphase. If a cell possesseda dominant mutation causing separase to be constitutively active and begin cleaving all cohesins prematurely during prometaphase (before the M checkpoint criteria were met), which outcome is the most likely and immediate consequence? (A) The resulting daughter cells would skip the G1 phase and immediately enter the S phase due to premature activation of maturation-promoting factor (MPF). (B) The cell would successfully complete mitosis, but the spindle poles would fail to move apart due to inactive non-kinetochore microtubules. (C) The M checkpoint would fall, and the liberated chromatids would segregate randomly, resulting in genetically unequal daughter cells. (D) The nuclear envelope would reform immediately, triggering early telophase and preventing the remaining spindle microtubules from attaching to kinetochores. (E) Cytokinesis would initiate during prophase, leading to the formation of multiple, small nuclei within a single parent cell.

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