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问题 选择题

利用酵母菌发酵生产酒精时，投放的适宜原料和在产生酒精阶段要控制的必要条件分别是（   ）。

A．玉米粉和有氧

B．大豆粉和有氧

C．玉米粉和无氧

D．大豆粉和无氧

答案

答案：C

根据酿酒的操作步骤进行分析回答．

解：白酒的酿造过程为：制曲---淀粉原料与霉菌混合，糖化---霉菌把淀粉分解成葡萄糖，发酵---在厌氧条件下，酵母菌把葡萄糖转变成酒精，蒸馏---将发酵液中的酒精进行分离、浓缩．玉米粉的主要营养物质为淀粉，大豆粉的主要营养物质为蛋白质，故投放的适宜原料是玉米粉，酵母菌只有在无氧的条件下才会把葡萄糖转变为酒精，故控制的必要条件为无氧．

故选：C

传统的酿酒原料是富含淀粉的谷物，白酒的酿造过程实际上是一个先后利用两类微生物进行发酵的酿造工艺．

单项选择题

A placebo is a chemically inert substance prescribed more for the mental relief of a patient than for its effect on the patient’s physical disorder. It is prescribed in the hope of instilling in the patient a positive attitude toward prospects for his or her recovery. In some cases, the placebo actually produces improvement in the patient’s condition. In discussing the use and effect of placebos, a well-known medical researcher recently paid physicians the somewhat offbeat compliment of saying that physicians were the ultimate placebo.
By comparing a physician to a placebo, the researcher sought to imply that

A．physicians should always maintain and communicate an optimistic attitude toward their patients, regardless of the prognosis.

B．the health of some patients can improve simply form their knowledge that they are under a physician’s care.

C．many patients actually suffer from imagined illnesses that are best treated by placebos.

D．physicians could prescribe less medication and achieve the same effect.

E．(E) it is difficult to determine what, if any, effect a physician’s behavior has on a patient’s condition.
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单项选择题

人身风险所致的损失一般有两种，即（）

A.物质损失和额外费用损失

B.收入损失和责任损失

C.额外费用损失和收入能力损失

D.物质损失和责任损失
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