在生态系统中，物质和能量沿______和______流动，有毒物质也能够沿着它们进行积累．
在生态系统中，植食性动物（消费者）直接以植物（生产者）为食，它们又是肉食性动物的食物；这样生产者与消费者之间就形成了吃与被吃的关系，它们形成的食物结构，叫做食物链．在一个生态系统中，一种动物往往有多种食物，同时一种植物或动物又为多种动物所捕食，这样不同的食物链便彼此交错，构成食物网．生态系统中的物质和能量就是沿着食物链和食物网流动．
故答案为：食物链； 食物网
| 完形填空。 One of the most famous movie prizes in the world is the Oscar. 1 in the United States, the Academy of Motion Picture Arts and Sciences gives Oscars to people who have done 2 the movies. There is an Oscar for the best movies of the year, another for the best actor, and Oscars for doing many other things well in the movies. Oscars are very important 3 people want to see movies that won them. They want to see actors who have won Oscars, 4 . This means that movies that have won Oscars make a lot of 5 . The Academy first gave prizes to movies 6 1927, but they were not called Oscars. That happened 7 four years. Most people think that Oscar was someone famous in the movies, but he 8 . He was no one important. He was someone that a woman called Margaret Herrick knew. She worked for the Academy and one day she saw the 9 on a table. She said, "He 10 my friend, Oscar." From that time on the prizes were called the Oscars. | ||||
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