农田生态系统中,假设有两条主要的食物链,如果有人大量捕杀青蛙,短期内对该生态系统

题型:选择题

问题:

农田生态系统中,假设有两条主要的食物链,如果有人大量捕杀青蛙,短期内对该生态系统造成的影响是(    )

A.有利于生态系统的平衡

B.水稻害虫严重

C.蛇的数量迅速增加

D.鼠的数量迅速增加

考点:生态系统的概念和组成食物链和食物网生态系统的多样性生态系统的自动调节能力生态系统的功能
题型:选择题

阅读理解。

     Mr. Smith works in an office. He is very busy and has no time to have a good rest.Every evening,when he

comes from his office, he's always tired and wants to go to bed early.But his wife often has a lot of interesting

things to tell him after supper.She doesn't stop talking until she falls asleep,but it's usually too late and Mr.

Smith has to get up in time in the morning when she is asleep.

     One day the man felt tirreble and couldn't go to work.He decided to go to see a doctor.And Mrs Smith went

to the hospital with him. Before her husband said what was the matter with him,the woman had told the doctor

all and the man understood why.He wrote out a prescription (处方). And when Mr. Smith brought the medicine

to the resulting room,the doctor said to her,"The bottle of medicine is for your husband and the pills are for

you.

     "For me?" the woman said in surprise,"I'm fine.I don't need anything medicine!" "I don't think so,madam,"

said the doctor."They are sleeping pills.Your husband will soon be all right if you take them." 

1. Mr. Smith is _______.

A. too busy to have a good rest.

B. too busy not to have have a good rest.

C. busy enough to have a good rest.

D. not busy enough to have a good rest.

2. The sentence "His wife doesn't stop talking until she falls asleep"means________.

A. she doesn't stop talking when she falls asleep.

B. she doesn't stop talking after she falls asleep.

C. She keeps talking until she falls asleep.

D. She likes talking as she falls asleep.

3. Why does Mr. Smith have to get up when his wife is asleep in the morning?

A. Because he can't fall asleep.

B. Because he has to go to work.

C. Because he doesn't want to sleep.

D. Because his wife ask him to get up.

4. Why couldn't Mr. Smith go to work one day?

A. Because he didn't want to work.

B. Because his wife didn't let hin go.

C. Because he fell ill.

D. Because he was too tired to go to work.

5. The sentence "Your husband will be all right if you take them."means Mr. Smith will

   soon be all right if ______.

A. Mrs Smith takes the bottle of medicine.

B. Mr. Smith takes the pills.

B. Mr. Smith takes the bottle of medicine.

D. Mrs Smith stops talking too much at night.

题型:选择题

由于子宫蜕膜层发育不良或完全缺如,胎盘绒毛直接植入子宫肌层

A.胎盘粘连
B.胎盘滞留
C.植入性胎盘
D.胎盘嵌顿
E.胎盘剥离不全

题型:选择题

单种培养

题型:选择题

雨点釉被称为()、();在日本被称为()。

题型:选择题

在隧道的超、欠挖测定中,______是用非接触法量测开挖断面的。

A.极座标法
B.使用激光束法
C.断面仪法
D.使用投影机法
E.直角坐标法

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