题干

某生物兴趣小组的同学做了“探究玉米种子萌发的环境条件”的实验:在甲、乙、丙、丁四个烧杯中分别放等量的棉花,再将相同数量的玉米种子放在上面,在不同条件下进行培养,数日后记录发芽情况如下:

装置

种子所处环境

实验结果

干燥的棉花,置于25℃的橱柜中

种子不萌发

潮湿的棉花,置于25℃的橱柜中

种子萌发

潮湿的棉花,置于冰箱冷藏室(4℃)

种子不萌发

棉花和种子完全浸没在水中,置于25℃的橱柜中

种子不萌发

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    Joseph Francis Charles Rock (1884–1962) was an Austrian-American explorer, botanist, and anthropologist(人类学家). For more than 25 years, he travelled extensively through Tibet and Yunnan, Gansu, and Sichuan provinces in China before finally leaving in 1949.

    In 1924, Harvard sent Joseph Francis Rock on a treasure hunt through China's southwestern provinces—the Wild West of their day. But gold and silver weren't his task: Rock, a distinguished botanist, sought only to fill his bags with all the seeds, saplings, and shrubs he could find. During his three-year expedition, he collected 20,000 specimens for the Arnold Arboretum(阿诺德植物园).

    Botany, though, was just one of Rock's strengths. As an ethnologist(民族学者), he took hundreds of photographs of the Naxi, a tribe in Yunnan province, recording their now-lost way of life for both Harvard and National Geographic, and took notes for an eventual 500-page dictionary of their language. His hand-drawn map of his travels through China's “Cho-Ni” territory, in the Harvard Map Collection, includes more than a thousand rivers, towns, and mountains indicated in both English and Chinese, and was so well made that the U.S. government used it to plan aerial missions in World War II.

    Scientist, linguist, cartographer, photographer, writer—Rock was not a wallflower in any sense. Arrogant and self-possessed, he would walk into a village or warlord's place “as if he owned the place,” said Lisa Pearson, the Arboretum's head librarian.

    In declaring his successful return under the headline “Seeking Strange Flowers, in the Far Reaches of the World,” the Boston Evening Transcript ran a large photo of the daring explorer wearing in a woolly coat and fox-skin hat. “In discussing his heroism including hair-raising escapes from death either from mountain slides, snow slides and robber armies, he waves the idea away as if it is of no importance.”

    The Arboretum and Rock parted ways after 1927, mainly because his trip cost Harvard a fortune—about $900,000 in today's dollars. Fortunately, many of his specimens, many of his amazing photos, and his great stories remain.