题型:阅读选择 题类:常考题 难易度:普通
江苏省永丰初级中学2020届九年级下学期英语开学考试试卷(含听力音频)
It may seem easy to say that plants and animals are different. Any child can tell the difference between a tree and a dog. But those differences are far deeper than just what they look like. The cells(细胞) that plants are made up of are different. In other words, the cell wall of plants has something special.
First of all, it's important to find that not all plant cells have a cell wall. Besides, there are many differences of a cell wall based on the kinds of plant. The following is meant to be what a plant cell wall is like.
The cell wall of a plant is on the outside of the cell membrane(膜). It is usually hard and cannot be bent easily, but the degree of flexibility(韧性) of the cell wall is different. It is based on the special use that the cell has in keeping the plant alive. Cells that make up the trunk of a tree are clearly less flexible than cells on a leaf.
Cell walls act in many ways. They serve to protect the plant. They provide support, as well as help in the movement of chemicals and wastes into and out of the cell. More importantly, they control the water that goes in and out. Plants must have good water controlling systems(系统), allowing them to keep water during dry seasons, and get rid of unnecessary water. Plants can't walk around to find water, so being able to control water is very important.
So there you have it —what a plant cell wall is. Of course, there are many other things that are not talked about here. Knowing more about plant cell walls requires further study and research.
How honey is made
{#blank#}1{#/blank#} The bee(蜜蜂) gets sweet juice from flowers with its mouth, which is shaped like a tube(吸管). Bees fly hundreds of times between flowers and their honeycombs(蜂巢). |
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{#blank#}2{#/blank#} In the country, some bees make their homes in places like the trunk of tree. Bees make honeycombs with wax (蜡) from their own bodies, The space in the honeycomb is where the honey is stored(储存). |
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{#blank#}3{#/blank#} In gardens or farms, beekeepers, keep bees in beehives(蜂箱) like this one so they can collect honey. About fifty thousand bees live in one beehive. |
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{#blank#}4{#/blank#} The beekeeper collects the honey from the beehives. He takes out the honeycomb which is full of honey. He wears special clothes so that he doesn't get bitten(咬). |
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{#blank#}5{#/blank#} Honey is used to make lots of different food. It is delicious when it is spread onto bread. |
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A. Where to store honey B. How to get flower juice C. Ready to eat D. How to collect honey E. Where to keep bees |
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