问题 选择题

在制作洋葱鳞片叶表皮细胞的临时装片时,下列操作方法正确的是(  )

A.实验开始时要先在洁净的载玻片中央滴一滴清水

B.用小刀切下一块厚薄均匀的洋葱鳞片叶作为观察材料

C.用镊子撕取一小块薄而透明的洋葱鳞片叶内表面,然后浸入水滴中央即可进行观察

D.盖上盖玻片后,将碘液直接加在盖玻片上进行染色

答案

制作洋葱鳞片叶表皮细胞临时装片方法步骤:

(1)用洁净的纱布把载玻片和盖玻片擦拭干净.

(2)把载玻片放在实验台上,用滴管在载玻片的中央滴一滴清水.

(3)用镊子把洋葱鳞片叶内侧撕取一小块透明薄膜--内表皮,把撕下的内表皮浸入载皮片上的水滴中,用镊子把它展平.

(4)用镊子夹起盖皮片,使它的一边先接触载玻片上的水滴,然后缓缓地放下,盖在要观察的材料上,这样才能避免盖玻片下面出现所泡而影响观察.

(5)把一滴稀碘液滴在盖玻片的一侧.用吸水纸从盖玻片的另一侧吸引,使染液浸润标本的全部.

A、实验开始时要先在洁净的载玻片中央滴一滴清水是准备过程.故选项A正确;

B、用镊子把洋葱鳞片叶内侧撕取一小块透明薄膜--内表皮,而不是一块厚薄均匀的洋葱鳞片叶.故选项B错误;

C、用镊子把洋葱鳞片叶内侧撕取一小块透明薄膜--内表皮,把撕下的内表皮浸入载皮片上的水滴中,用镊子把它展平后,再盖盖皮片、染色.故选项B错误;

D、染色是把一滴稀碘液滴在盖玻片的一侧,用吸水纸从盖玻片的另一侧吸引,使染液浸润标本的全部.故选项B错误;

故选:A

填空题
阅读理解

Cittaslow has discovered China, and it is awarding a little village in Jiangsu the title of "slow city"

The bored teenagers of Gaochun are impatient with the leisurely pace of hometown life.For them there is no nightlife to speak of, no bright lights, no excitement and they cannot wait to grow up and leave for the urban attractions of the big cities.But it is this laid-back lifestyle that has attracted international attention.At least, a quiet village within Gaochun county has come under the spotlight.Yaxi village, population 20,000, is about to be designated China's first "slow city" by Cittaslow, the sustainable lifestyle movement that first surfaced in Italy 11 years ago.

At home, the residents at Yaxi are unfazed and pretty much unimpressed by the honor.To them, life has been like this for as long as they can remember.Here, growing old gracefully is natural.

Nobody living in this little county had heard of Cittaslow or the words "slow city" before this.

"The first time I heard the term was last July, when the vice-president of Cittaslow, Angelo Vassallo, visited Yaxi village," says Zuo Niansheng, the chief editor of local newspaper Gaochun Today.

"Vassallo was deeply impressed by this village's natural and cultural resources and said it perfectly fitted the requirements for a slow city," says Zuo."That was how Yaxi became connected with Cittaslow.

The Slow City must also be committed to protect and maintain the natural environment as well as promote a sustainable way of development ?all of which are the current strategies adopted in Gaochun."We've been doing this for years," adds Zuo.

Cittaslow was founded in Tuscany, Italy in 1999.It was a spin-off from the Slow Food movement which started, also in Italy, in 1986 as a protest against the first McDonald ' s opening near the Spanish Steps in Rome.The movement championed a return to healthy, nutritious home-grown, home -cooked food.

Slow Food has since expanded globally to more than 130 countries.Its mission has also broadened to include the promotion of sustainable foods and local small businesses, and the localization as opposed to globalization of food production.

Cittaslow is an expansion of the Slow Food movement, and it actively advocates a lifestyle that is sustainable, that will improve quality of life, and will preserve cultural and culinary (烹饪的)heritage.

小题1:According the passage, Cittaslow is a(n) ____.

A.organization

B.person

C.lifestyle

D.honor小题2:What' s the reaction of the residents at Yaxi to the award according the passage? They feel

A.very excited.

B.very shocked

C.indifferent

D.very happy小题3:Why is the village Yaxi awarded the title of “slow city”? Because          .

A.it is full of excitement and activities of nightlife

B.the residents at Yaxi enjoy a leisure life

C.it is very rich and has a lot of attractions

D.foreign people like small towns than big cities.小题4:It can be inferred from the passage that         .

A.young people at Yaxi enjoy their life very much

B.China is more and more popular with foreign people

C.the first McDonald’s in Europe was opened in Spain

D.the lifestyle of “slow city” will be good to environment and people