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芽孢杆菌生长到一定阶段，菌体内一端形成芽孢，另一端形成一种被称为伴孢晶体的蛋白质晶体。菌体破裂后释放出芽孢和伴孢晶体，伴孢晶体本身并无毒性，是毒素的前体。当昆虫吞食伴孢晶体后，在肠道内碱性环境条件和特定的蛋白酶的作用下，伴孢晶体变成毒素分子，能使小肠上皮细胞萎缩退化，昆虫停食，最后脱水死亡。科学家利用芽孢杆菌的这个特性，在实验室大量培养，制成生物农药，洒在农作物上，让害虫吃后中毒死亡。或利用基因工程技术，把芽孢杆菌的抗虫基因转到农作物体内，培育出抗虫品种。请根据上述材料回答下列问题： 芽孢杆菌的抗虫基因转到农作物体内后，也能产生伴孢晶体蛋白，说明（）
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B.
【简答题】（11·西宁）如图9是三种化合物的结构式及分子式，则按其规律第4个化合物的分子式为 _ ▲ ．
【单选题】In recent years many cabinetmakers have been winning acclaim as artists. But since furniture must be useful, cabinetmakers must exercise their craft with an eye to the practical utility of their produ...
A.
Some furniture is made to be placed in museums, where it will not be used by anyone.
B.
Some cabinetmakers are more concerned than others with the practical utility of the products they produce.
C.
Cabinetmakers should be more concerned with the practical utility of their products than they currently are.
D.
An object is not an art object if its maker pays attention to the object's practical utility.
E.
Artists are not concerned with the monetary value of their products.
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A.
div:hover{transform:rotate(45deg)}
B.
div:hover{transform:translate(50px)}
C.
div:hover{transform:scale(1.5)}
D.
div:hover{transform:skew(45deg)};
【单选题】Grand Opening Celebration! Mill Creek Company 20 Queens Street(Opposite Jacksons Furniture) Salem, OR 23698 356-276-3698 Free meal coupon with purchase of $ 30 or more(Harding Store Only) Grand Openin...
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Apparel
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Books
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Food
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