题干

植物体细胞在生长过程中,液泡的变化是()

A:数目增加,体积增大

B:数目减少,体积增大

C:数目增加,体积不变

D:数目减少,体积不变

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B

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       An environmental group called the Food Commission is unhappy and disappointed because of the sales of bottled water from Japan. The water, it angrily argues in public, has traveled 10,000 “food miles” before it reached Western customers. Transporting water halfway across the world is surely the extremely stupid use of fuel when there is plenty of water in the UK. It is also worrying that we were wasting our fuel by buying prawns from Indonesia (7,000 food miles ) and carrots from South Africa (5,900 food miles).

        Counting the number of miles traveled done by a product is a strange way of trying to tell the true situation of the environmental damage due to industry. Most food is transported around the world on container ships that are extremely energy efficient. It should be noticed that a ton of butter transported 25 miles in a truck to a farmers' market doesn't necessarily use less fuel on its journey than a similar product transported hundreds of miles by sea. Besides, the idea of “food miles” ignores the amount of fuel used in the production. It is possible to cut down your food miles by buying tomatoes grown in Britain rather than those grown in Ghana. The difference is that the British ones will have been raised in heated greenhouse and the Ghanaian ones in the open sun.

       What is the idea of “food miles” does provide, however, is the chance to cut out Third World countries from First World food markets. The number of miles traveled by our food should, as I see it, be regarded as a sign of the success of the global trade system, not a sign of damage to the environment.