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1问题李尉军[湖北省黄冈中学]、郑长军[黑龙江省大庆市林甸县第一中学]两位老师在“互动平台”栏目网上讨论区提出了以下话题:人教版高中《生物·必修1·分子与细胞》P.31认为“淀粉不易溶于水”。这一说法准确吗?上述教材配套的教师用书(P.47)认为:天然淀粉一般含有两种组分:直链淀粉和支链淀粉,多数淀粉所含的直链淀粉与支链淀粉的比例为(20%~25%):(75%~80%)。蜡质玉米和糯米等几乎只含支链淀粉……纯的直链淀粉仅少量地溶于热水,溶液放置时重新析出淀粉晶体。支链淀粉易溶于水形成稳定的胶体,静置
1 question Li Weijun [Hubei Huanggang Middle School], Zheng Changjun [Daqing City, Heilongjiang Province, Lindian County middle school] two teachers in the “interactive platform” column online forum put forward the following topics: PEP high school “Biology compulsory 1 · molecules and cells ”P.31 that “ starch is not soluble in water ”. This statement is accurate? The textbook supporting teacher (P.47) that: natural starch generally contains two components: amylose and amylopectin, amylum starch contained in most starch amylopectin ratio (20% ~ 25%) :( 75% ~ 80%). Waxy corn and sticky rice contain almost only amylopectin ... Pure amylose is only slightly soluble in hot water and the starch crystals are re-precipitated when the solution is placed. Amylopectin soluble in water to form a stable colloid, standing