问题 阅读理解

阅读理解。

     MSG (monosodium glutamate) is a food additive (食品添加剂), which has been widely used by many

food factories all over the world since it appeared first in Japan in 1909.

     MSG is a substance that is added to some food to improve its original (原先的) taste and colour. It is

used in foods around the world such as cakes, bread, frozen meats, fish and vegetables. In the beginning,

people thought MSG was safe just like salt and sugar. However, in 1968 some people reported they seemed

to have bad reactions (反应) to MSG after having had a meal at a restaurant. They included headaches and

quick heartbeat (心跳). It was also reported that MSG excited a person's brain and caused his death in Japan.

Scientists think that MSG may lead to many neurological disorders (神经紊乱). In mice studies done by a

university, the evidence showed the mice didn't want to eat the food including MSG.

     Today many food companies"hide" MSG on food labels (标签) by using different names. If you see

"natural flavorings", "hydrolyzed protein" and "spices" in a food label, you are probably seeing a hidden way

to "report" MSG in a food label. Every time we have a meal in a restaurant, we always feel the food very

delicious to taste, but sometimes it is dangerous for our health because some poisonous food additives have

been added to the food.

     To protect people's health, our governments, from central to local, are taking actions to stop factories

producing poisonous food additives.

1. Monosodium Glutamate is _______.

A. a food

B. an additive

C. a factory

D. a country

2. MSG is often used in _______.

A. frozen meats

B. cups

C. clothes

D. book covers

3. The examples in the second paragraph tell us ________.

A. the food including MSG is delicious

B. people like to eat in a restaurant

C. mice like eating the food including MSG

D. MSG is not safe sometimes

4. If you see "natural flavorings", "hydrolyzed protein" and "spices" in a food label, you will know—________.

A. you must eat the food in a hidden way

B. the food label must be hidden

C. MSG is probably added to the food

D. you must report the food to your parents

5. The underlined word "substance" in the article means __________.

A. colour

B. material

C. taste

D. food

答案

1-5     BADCB

填空题
问答题

(1)用游标为20个小等分刻度的游标卡尺测量一工件的宽度,得到如图1所示中的游标卡尺的读数,图中游标卡尺的读数为______cm.

(2)为测定一节干电池的电动势和内阻,用如图2所示电路.除干电池、开关、导线外可供使用的实验器材还有:

A.电流表(量程0.6A   3A)

B.电压表(量程3V  15V)

C.滑动变阻器(阻值范围0~10Ω  额定电流2A)

D.滑动变阻器(阻值范围0~200Ω  额定电流1A)

请你完成下面的选择:电流表量程选______,电压表量程选______,滑动变阻器选______.(填器材前面的字母代号)

(3)某实验小组为测量一只微安表G1的内阻,采用了以下的方法:

实验器材:一只待测的微安表G1;一只标准电流表或量程较大(或与待测表相同)的标准微安表G2;一节干电池;0~9999Ω的电阻箱一只;单刀双掷开关一只;导线若干.

实验步骤一:将开关S断开,按图3所示连接电路.

实验步骤二:使开关掷向b端,此时电路中通过微安表G1的电流较小,调节电阻箱R使微安表G1的示数接近满偏,记下此时电阻箱R的阻值R1和标准微安表G2的读数I.

实验步骤三:将开关掷向a端,并调节电阻箱R使标准微安表G2示数维持电流I不变,记下此时电阻箱R的阻值R2

由以上步骤可以测得微安表G1的内阻为Rg=______.

请指出该同学在实验中的疏漏:______.