题干

下列有关生物学实验中的说法正确的是(    )

A:发芽的种子研磨液中含有还原性糖,加入斐林试剂,试管内立即呈现砖红色沉淀

B:用苏丹Ⅳ鉴定含油多的细胞,显微镜下可见染成橘黄色的颗粒

C:观察叶绿体的实验制作临时装片时,先在载玻片中央滴一滴健那绿染液

D:“观察DNA和RNA在细胞中的分布”实验中需要用甲基绿吡罗红的混合液染色

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D

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    Paying a higher price than usual for a ticket to see a film in 3D is the annoyance of many a cinema-goer's life.

    But there may be a benefit to doing so, as a study has found that 3D films exercise the brain and improve short-term functioning in a similar way to brain-training tests.

    The research found that people who watched a movie in 3D improved cognitive (认知) skills, compared to those who watched it in 2D.

    The research was led by neuroscientist(神经学家) Dr Patrick Fagan from Goldsmiths University in London. More than 100 people took part in the experiment, where participants watched Disney film Big Hero 6 in either standard format or RealD 3D.

    They also carried out a brain-training-style test before and after seeing a section from the film. The test covered memory, reaction times and cognitive function and the results were compared later.

    According to the research, which was carried out in partnership with science group Thrill Laboratory, participants experienced a 23 percent increase in cognitive processing, as well as an 11 percent increase in reaction times.

    Dr Fagan said that the results showed enough of an improvement in brain function to suggest that 3D could play a part in improving brain power in the future.

    "These findings are more significant than you might think," he said. "It is a fact that people are living longer and there is a noticeable decline in cognitive brain function in old age which can worsen future quality of life. There has never been a better time to look at ways to improve brain function. The initial results of this study show that 3D films may potentially play a role in slowing this decline."

    A second part of the experiment involved those watching the film being fitted with headsets that scanned brain activity and this too showed heightened (加强的) activity when watching 3D. According to the results, participants were seven percent more engaged with what they were watching, adding to argument that 3D movies are more like watching real-life—something Professor Brendan Walker from Thrill Laboratory agreed with.

    "As Professor Brendan Walker's test concluded, 3D films are more attractive and heighten the senses — this, in turn, makes the brain run at quicker speeds," Dr Fagan said.