题干

下列关于细胞的分化、衰老、凋亡的叙述,正确的是(  )

A:在细胞衰老和凋亡的过程中,细胞核的体积不断变小

B:细胞分化的过程中遗传物质不发生改变,但mRNA的种类和数量会改变

C:高度分化的细胞不具有分裂能力,故细胞核中的DNA不存在解旋的现象

D:细胞生长过程中体积增大,与外界环境进行物质交换的速率增强

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B

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    It is made from grapes grown without pesticides (杀虫剂) and chemicals, is kind to the environment and rarely causes hangovers (酒后头痛). Sales of organic wine are booming in the UK.

    According to the organic food and farming group Soil Association, sales of organic beers, wines and spirits rose by 14.3% last year to reach nearly £6 million, driven by the demand from consumers who are increasingly seeking “natural” food.

    “It seems that people are rediscovering their link with the environment through organic food. Organic wines also taste better, perhaps due to less use of man-made chemicals.” said Finn Cottle of Soil Association. As well as the benefits of producing grapes without using pesticides, organic wine also contains less sulphur dioxide (二氧化硫), which can contribute towards hangovers.

    Supermarkets are increasing supplies on their shelves to meet consumer demand, while the switch to online shopping has also helped, as people are more easily able to find what they are looking for. Vintage Roots is now one of the UK's biggest online shops of organic wine, while Ocado provides more than 100 different organic wines and Daylesford, best-known for its organic vegetable boxes, has branched out into organic wine and spirits.

    The discount supermarket Aldi is set to start its first collection of so-called “green” wines this week, offering eight wines with organic certificates. Aldi expects the wines to appeal to the young shoppers who are increasingly concerned about the environmental influence of the produce that they are buying and consuming.

    English organic wine producer Oxney Estate's Noir Rosé recently won the Waitrose prize for the most outstanding rosé wine at the competition. A spokeswoman for Waitrose said: “Organic wine is a growing trend globally and we have seen sales increase by 16% in the last year”.

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