问题 选择题

青蛙生殖和发育的特点是

A.雌雄同体、体外受精、体外发育

B.雌雄同体、体内受精、体外发育

C.雌雄异体、体外受精、水中发育

D.雌雄异体、体内受精、水中发育

答案

答案:C

题目分析:青蛙是两栖动物。青蛙属于雌雄异体动物,青蛙生殖时,雌雄蛙抱,分别将精子与卵细胞排到水中,精子与卵细胞在水中结合,因此是体外受精,受精卵在水中发育成蝌蚪,蝌蚪继续发育成成蛙,所以青蛙是水中发育的。选项C符合题意。

阅读理解

阅读理解。

                                                                  Rainy Day Fun

     You wake up and the weather is all wet. What are you going to do today? Here are four ideas for you

to try when it's raining cats and dogs.

     Puppet (木偶) show

     You can create your own puppets with things your parents already have around the house. First, you'll

need some old socks or brown paper bags. Then get them decorated. Give your puppets names and funny

voices. You might want to make up a special story for them. Maybe one puppet lost his way home. Maybe

another puppet has superman powers. To make your show even better, use a cardboard box as a stage.

Build a castle Ask your parents for some old sheets, blankets, or comforters. Spread them over chairs or

other furniture to create a top-secret castle. Bring a flashlight, a good book to read, and maybe even a snack.

     Dress-up time

     Both boys and girls can have fun trying on old clothes. Ask your parents to let you try on old hats,

jewelry, shoes, and clothes. Do you want to be a doctor? You can pretend it in a doctor coat. Or maybe you

see yourself as a movie star. Ask your mom for her old dance dresses. Don't forget the earrings and high

heels!

     Say thanks

      Birthdays and holidays are chances for us to thank people who love us. But it can be a special treat to

get a gift or a card on an ordinary day. Think of the people who make you happy and then come up with

a way to show them your care. Use your arts and craft supplies to create a special card. Or ask your

parents to help you make cookies as a gift for that special person. You will be delivering sunshine on a

rainy day!

1. According to the passage, these activities can happen on ______.

A. sunny days

B. rainy days

C. cloudy days

D. windy days

2. When working on the puppet show, children can ______.

A. train their own imagination

B. learn to perform shows on stage

C. know how to deal with others

D. find new ways of creating puppets

3. Which of the following words can be used to describe the kids' castle?

A. Boring

B. Hot

C. Quiet

D. Noisy

4. What can we learn from the passage?

A. You can pretend to be a doctor by trying on your parent's clothes.

B. You can only give a gift or a card to show your care on birthdays or holidays.

C. You can use your own dance dresses to dress up.

D. You can make some gifts to show your care for special persons.

单项选择题 A1/A2型题