问题 问答题 简答题

为什么蓝细菌能极其广泛地分布于自然界?

答案

参考答案:因为:为光能自养型微生物,能进行光合作用;有的具固氮作用;菌体外面包有胶质层,可保持水分,耐受干燥能力强;可与多种植物进行共生。

阅读理解

Can dolphins talk? Maybe they can’t talk with words, but they talk with sounds. They show their feelings with sounds.

Dolphins travel in a group. We call a group of fish a “school”. They don’t study, but they travel together.

Dolphins are mammals(哺乳动物), not fish, but they swim together in a school. Dolphins talk to the other dolphins in the school. They give information. They tell when they are happy or sad or afraid. They say“welcome”when a dolphin comes back to the school. They talk when they play.

They make a few sounds above water. They make many more sounds under water. People can’t hear these sounds because they are very, very high. Scientists make tapes of the sounds and study them.

Sometimes people catch a dolphin for a large aquarium.(An aquarium is a zoo for fish.) People can watch the dolphins in a show. Dolphins don’t like to be away from their school in an aquarium. They are sad and lonely.

There are many stories about dolphins. They help people. Sometimes they save somebody’s life. Dolphin meat is good, but people don’t like to kill them. They say that dolphins bring good luck. Many people believe this.

小题1:A school of dolphins means_____.

A.a zoo for dolphins

B.a show by dolphins

C.a group of dolphins

D.a library of dolphins小题2: A dolphin feels _____in an aquarium.

A.afraid

B.happy with people watching them

C.lucky

D.sad and lonely小题3:Which sentence is true?

A.Dolphins talk with words.

B.Dolphins always bring good luck.

C.Dolphins make more sounds above water.

D.Dolphins can’t breathe(呼吸) under the water.小题4:People can’t hear the dolphins’ sounds because they are         .

A.low

B.high

C.soft

D.quiet小题5:From the passage we know_____.

A.Dolphins travel together.

B.Dolphins talk with words when they play.

C.Dolphins like to live in aquariums.

D.All people want to catch dolphins and eat them.

单项选择题