题干

如图为生态系统碳循环示意图.下列说法正确的是(  )(①②③是生物,a、b是生理过程)

A:①是生产者、②是消费者、③分解者

B:由图中的①②③就可以组成一个生态系统

C:a过程是呼吸作用

D:如果此生态系统是海洋生态系统,则①主要是原生生物中的藻类

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D

同类题4

A) 请认真阅读下列短文,并根据所读内容填入一个最恰当的单词。

注意:每个空格只填1个单词。

    More and more British people are deciding not to eat meat and animal products. As a result, vegetarianism(素食主义) is increasing in the UK. According to the Vegetarian Society, 2000 people are giving up meat and “going veggie(素食)” in Britain every week. There's even a National Vegetarian Week organized every year to encourage people to try a meat-free lifestyle.

Vegetarians and vegans

    Vegetarians are people who don't eat or use any animal products. They are becoming more and more common in the UK culture. A recent survey showed that 3 million people (5.7 percent of the country's population) were vegetarians.

A healthy diet

    So why are British people cutting out meat? Many are unhappy about the poor treatment of animals and the effects of meat and fish production on the environment. Worries about food safety, for example mad cow disease, also play a part. Others choose to change their eating habits to get healthier. According to the Vegetarian Society, a meat-free diet could help prevent the certain cancers, as well as heart disease and high blood pressure(压力).

Organic(有机的) farming

    Another rising trend appears in the UK's food production. They want their food to be organically produced. Organic farmers use very few or no chemicals. Organic meat is produced without the use of drugs. Organically farmed animals also have more living space and more good food. According to the Soil Association, three out of every four UK families now buy some type of organic food.

Vegetarianism is becoming____ in the UK

Vegetarianism is increasing in the UK ____ more and more British people are choosing to live a meat-free style.

The government ____ a National Vegetarian Week every year to encourage people to stop eating meat.

Vegetarians and vegans

Vegetarians don't eat or use any ____ products.

It is reported that the ____ of vegetarians in the UK is about 3 million .

A healthy diet

Three____ for cutting out meat

Some people think the production of meat and fish may harm both the animals themselves and the____

Some people are____ about food safety. They don't think the meat they eat are safe enough.

A meat-free diet could help reduce the ____ of the certain cancers, as well as heart disease and high blood pressure.

Organic farming

Organic farmers use very few or no chemicals. Organic meat is produced without ____ drugs.

At present, about 75% of UK families buy some type of organic food.