首页>雅思>雅思口语>正文
雅思口语考试话题素材积累_科学课

www.zige365.com 2012-10-9 10:29:44 点击:发送给好友 和学友门交流一下 收藏到我的会员中心

  This is very exciting to observe! What happened to the penny? It turned green.

  Coloured Flower 变色的花

  Materials you will need:

  Water

  Scissors

  Food Colouring

  Jar, Plastic Cup or Test Tube

  A Flower (light coloured-white carnation) or Celery Stalk (with leaves)

  This is a colour changing experiment.

  Steps:

  1. Fill the cup with water.

  2. Add a few drops of food colouring

  3. Cut the end off the stem (stalk)

  4. Put the flower in the water

  Watch and in time the food colouring will be sucked up the stem along tiny tubes (called vessels) and the petals of the flower will start to change in colour.

  Another way to try this experiment is to get a flower with a long, thick stem (or a celery stalk with leaves) and slit it carefully from the bottom and put one end in separate test tubes (with different food colourings). Your flower (or celery) should have petals (or leaves) in two different colours.

  Did you know that plants need water to live? As well as absorbing water from the atmosphere (air) through their leaves, they suck water up through their stems. If you used the celery stalk for the above experiment you could cut the stalk and see that the little holes inside are coloured.

本新闻共3页,当前在第3页  1  2  3  

我要投稿 新闻来源: 编辑: 作者:
相关新闻