题型：阅读选择 题类： 难易度：困难
广东省深圳市南山育才教育集团2024-2025学年九年级上学期期中试卷
Blue is a very common color in our lives-the sky, the sea and even face masks are often blue. But this color is not frequently(经常) seen in plants. Why is that?
A. Because blue plants would blend in(融合) with the sky and sea.
B. Because animals prefer to eat blue plants.
C. Because the material that gives plants a blue color is rare(稀有的)
D. Because blue isn't a beneficial(有助的)color for plant growth.
The correct answer is D
There is no true blue pigment(色素)in nature. When light hits an object(物体), the object absorbs(吸收)some colors and reflects(反射)others. For example, plants look green because they reflect green light and absorb other colors. Blue light offers more energy than other colors. However, if a plant has blue leaves, according to scientists from the University at Adelaide in Australia, it must absorb(吸收) very small amounts of energy while reflecting high-energy blue light. This is not a good strategy(策略) for growth.
Less than 10 percent of plants are blue. Plants make blue flowers by mixing pigments. For example, anthocyanins(花青素)can turn into a blue-likes color with a certain amount of acidity(酸度). Plants may make use of this unique color to attract pollinators(传粉者), such as bees.
Kate and her friends play hide-and- seek(捉迷藏) at her home. Where are her friends? Canshe find them?
Who | Where is he/ she? | How does Kate find him/ her? |
Linda | She is in Kate's grandmother'sroom. | There is only a bed in the room. ThenKate sees her behind the door. |
Mike and Paul | They are under the bed. | Jack's bag is on the bed. He likes thebag very much. |
Jenny | She is under the table. | Kate sees her green hat. |
Frank | He is not under the desk. He isnot under the sofa. | Kate can't find him. Where is he? |
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