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26. T4 噬菌體是一種雙股 DNA 病毒,其中一個可被宿主轉錄/轉譯的基因製造出一種酵 素,可以破壞宿主細胞本身的 DNA,但病毒的 DNA 卻無恙。這是因為病毒 DNA 上的哪一種鹼基已被修飾過? (A) 腺嘌呤 (adenine; A) (B) 尿嘧啶 (uracil; U) (C) 鳥糞嘌呤 (guanine; G) (D) 胞嘧啶 (cytosine; C) (E) 胸腺嘧啶 (thymine; T)

42 下列何者不是古典學派的主張? (A)物價變動造成名目工資等比率變動 (B)勞動邊際產量等於名目工資 (C)賽依法則 (D)貨幣需求是名目工資的一個固定比例

1. 一位工人不小心打翻了 溶液,污染他的皮膚 10 cm2,污染活度為 3700 Bq,則污染 皮膚的劑量率為多少 Gy/h? (  貝他粒子的平均能量 = 0.7 MeV,在組織之質量吸收係數為 9.18 cm2/g) (A) 6.42×(B) 1.28×(C) 6.42× (D) 1.28×

2. 一束準直良好的射束含有 105 個光子,而光子能量為 10 MeV,射束打在 20 cm 厚的碳 塊上(密度 2250 kg/m3)。10 MeV 光子與碳作用的質量衰減係數(μ/ρ)為 0.0196 cm2/g,質 量吸收係數( )為 0.0138 cm2/g。請問在碳塊裡的 10 cm 深處 1 mm 厚 (在 10.0 cm 到 10.1 cm 間) 碳層的吸收能量(MeV)? (A) 207 (B) 876 (C) 1993 (D) 2200

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.