题干

下列关于动物生殖发育的叙述正确的是(  )

A:所有的鸟卵在适宜的条件下都可以发育成雏鸟

B:青蛙为体内受精、变态发育

C:美国白蛾的发育过程是:受精卵→幼虫→蛹→成虫

D:“蚕茧”是家蚕的幼虫时期

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答案(点此获取答案解析)

C

同类题2

阅读短文,下列问题

 B

    Did you know that each day one person in the US throws away 4.4 pounds of rubbish? Almost every month, we throw away our own rubbish in packaging alone. Packaging (including boxes, bags, etc.) comes to our homes with the things we have bought. Several weeks ago, the TV news said that in a city in Italy tons of rubbish were piled up in the streets, and the smell was rather terrible. What can we do to help? We should get to know the following Rs.

Reduce  

    To reduce means to make less rubbish. That is one of the first things we all should do for the environment. Reduce your rubbish by doing things like packing your lunch in reusable containers (可再利用的容器), taking smaller portions (份) at dinner so you don't waste food when you have had enough, writing on both sides of paper, and using less water when taking a shower.

Reuse   

    To reuse is to use things again. Think about the bags you get from the store. They can be reused to carry your lunch, to hold your rubbish, or to collect used cans. You can even take them back to the store the next time to carry your things instead of getting a new bag!

Recycle(回收利用)  

    Recycling is an important part of keeping our planet clean and green. It can also save energy. Be sure that you don't throw things in the rubbish that can be recycled to make something else. Paper, plastic, cans and bottles can all be recycled, but food, electrical waste and mobile phones can't. When you are not sure whether something can be recycled, go to your parents and teachers for advice.

    Follow the three Rs, and every one of us can do something to save the earth. It is also the best way to save ourselves.

同类题3

Zhang Lili: The most beautiful teacher in China

    Zhang Lili is a teacher at No.19 Middle School in the city of Jiamusi, Heilongjiang province. These days, many people think she is the most beautiful teacher in China, because she saved her students from a traffic accident (交通事故) on May 8, 2012.

On that day, Zhang and her two students were crossing the road outside the school gate when a bus suddenly lost control (控制) and ran fast towards them. Zhang pushed both students out of the way, but she herself was hit (被撞倒) by the bus. As a result, the 29—year—old teacher lost her legs.

The principal of No. 19 Middle School, Jiamusi City, said, "Zhang is a great teacher in our school. She’s also the most popular teacher among the students. For the students, she is like a sister. They call her Beautiful Sister. After hearing about this accident, all the students in her class cried." But Zhang is more than a teacher and sister to the 53 students in her class. She cares about their studies and even their lives.

Zhang’s bravery and kindness moved (感动) a lot of people in China. Many people visited her and sent her beautiful flowers and cards. They all hope she can get better soon and live happily for the rest of her life.

The most ____teacher in China

____ 

May 8, 2012

Where

 ____  the school gate of No.19 Middle School in Jiamusi

Who

Zhang Lili and her two____ 

How

A bus lost control and ran fast ____  them.

Zhang pushed the students away and was hit by the bus.

Social influences (影响)

Zhang is ____  among the students because she cares about ____  their studies and lives.

Many people are moved because Zhang is brave and____ .

A lot of____  people came and sent her beautiful flowers and cards.

Everyone hopes the beautiful teacher can have a____ life until the end of her life.