31.Which statement best predicts the consequence of histone acetylation at promoterproximal nucleosomes?
(A) Tightened DNA wrapping via increased histone positive charge
(B) Recruitment of chromatin remodelers and increased transcriptional competence
(C) Direct inhibition of RNA polymerase II elongation by blocking carboxy-terminal domain (CTD) phosphorylation
(D) Preferential increase of RNA polymerase III transcription
(E) Stabilization ofnucleosome core leading to reduced transcription factor binding

32. What is the primary biochemical basis for the fidelity of amino acid incorporation? (A) Codon-anticodon hydrogen bonding (B) Ribosomal peptidyl transferase selectivity (C) Editing (proofreading) by aminoacyl-tRNA synthetases (D) EF-Tu GTP hydrolysis timing (E) Initiation factor discrimination

33. If the Shine-Dalgarno sequence were mutated but AUG remained intact, the most likely outcome would be: (A) Perfeetly normal translation (B) Increased initiation at incorrect downstream AUGs (C) Frameshifting during elongation (D) Failure of termination (E) Increased tRNA mischarging

34. Which kinetic parameter best reflects catalytic efficiency at low substrate concentrations? (A) Vmax (B) Km (C) kcat (D) Kcat/Km (E) 1/Km

35. A hypothetical organism uses DNA but replaces all cytosines with 5- methylcytosine. What major risk would increase? (A) Loss of replication (B) Higher mutation rate via deamination (C) Frameshift instability (D) Reduced transcription (E) Loss of helicity

36. Which combination of defects would be synthetically lethal (cell survives with either alone but dies with both)? (A) Proofreading exonuclease + mismatch repair (B) Ligase + helicase (C) Primase + ligase (D) Gyrase + helicase (E) Clamp + polymerase

37. Which defect would most strongly increase frameshift mutations in repetitive DNA? (A) Helicase defect (B) Ligase defect (C) Mismatch repair defect (D) Gyrase defect (E) Primase defect

38. An enzyme exhibits normal Michaelis-Menten kinetics at pH 7 but displays sigmoidal kinetics at pH 9. Which explanation is most plausible? (A) Enzyme concentration doubled (B) Competitive inhibitor formed (C) Product inhibition dominates (D) Substrate precipitation occurred (E) Subunit ionization alters allosteric cooperativity NTHU115

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.

40. The Na+/K+ pump is a critical electrogenic transport protein that uses ATP to actively move ions against their concentration gradients, contributing to the membrane potential of animal cells. This integral protein is synthesized in the Endoplasmic Reticulum (ER) and modified through the Golgi apparatus before insertion into the plasma membrane. The completed pump moves 3 Nat ions out of the cell and 2 K+ ions into the cell. Considering the required sidedness of the plasma membrane, which component of the Na+/K+ pump is exposed to the ER lumen during the initial stages of synthesis? (A) The segment of the protein that releases the terminal phosphate group derived from ATР. (B) The region of the protein that initially binds the three Nat ions. (C) The binding domain that triggers the release of the two K+ ion into the cytoplasm. (D) The nonpolar a-helical stretches that span the lipid bilayer. (E) The binding site that has a high affinity for K+ ions when the pump has been phosphorylated.

41. A highly active muscle cell is subjected to extreme mechanical work, causing a sharp, sustained acceleration in the rate of ATP hydrolysis. The initial free energy released by this process is used primarily for mechanical work, such as muscle contraction. Considering the subsequent shift in the concentrations of ATP, ADP, and inorganic phosphate (Pi) within the cell, which statement best describes the immediate, self-regulating response mediated by allosteric control mechanisms? (A) The accumulation of inorganic phosphate (Pi) acts as a competitive inhibitor, competing with substrate molecules for the active sites of catabolíc enzymes, thus slowing down ATP synthesis. (B) The reduction in ATP concentration stabilizes the inactive form of key catabolic enzymes, causing the overall pace of catabolism to decrease. (C) The remaining ATP binds to its specific regulatory sites on anabolic enzymes, inhibiting them, while simultaneously promoting the activity of catabolic enzymes. (D) The rising concentration of ADP functions as an allosteric activator, stabilizing the active conformations of key catabolic enzymes and thereby accelerating the overall rate of ATP regeneration. (E) The decrease in ATP concentration forces the cell's metabolic pathways closer to equilibrium, which increases the amount of work the cell can perform, according to the Free Energy principle (AG).

115年 - 115 國立中山大學_學士後醫學系招生考試試題：普通生物及生化概論#138369

115年 - 115 學士後醫學系招生考試試題：普通生物及生化概論#138357

115年 - 115 國立清華大學_學士後醫學系單獨招生試題：生物與生化#138208

115年 - 115 國立中興大學_學士後醫學系公費生招生考試：普通生物及生化概論#138023

114年 - 114 學士後醫學系招生考試試題：普通生物及生化概論#126681

114年 - 114 國立中興大學_學士後醫學系公費招生考試：普通生物及生化概論#126435

114年 - 114 國立中山大學_學士後醫學系招生考試試題：普通生物及生化概論#126236

114年 - 114 國立清華大學_學士後醫學系考試︰生物生化#126232

113年 - 113 國立中興大學_學士後醫學系公費招生考試：普通生物及生化概論#119946

113年 - 113 國立清華大學_學士後醫學系招生考試_學士後醫學系：生物及生化#119851