【名词&注释】
两性花(hermaphrodite flower)、社会必要劳动时间(social necessary labor time)、社会劳动生产率(productivity of social labour)、阅读文章、显微镜观察(microscope)、单性花(unisexual flower)、无花果属(ficus)、染色体。
[单选题]使用显微镜观察洋葱根尖细胞染色体的基本步骤包括：①调节细准焦螺旋；②转换高倍镜；③把分裂中的细胞移至视野中央；④将洋葱根尖永久装片放在低倍镜下观察。正确的操作顺序是
A. ①②③④
B. ②①④③
C. ③②④①
D. ④③②①
查看答案&解析
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举一反三：
[单选题]The third paragraph is developed mainly by __________.
A. providing different examples
B. following the order of space
C. making comparisons
D. analyzing causes
[单选题]无花果属(ficus)植物的隐头花序中，( )能结实。
A. 短花柱花
B. 长花柱花
C. 两性花
D. 单性花(unisexual flower)
E. 无被花
[单选题]阅读文章回答第69~72题D Andrew Ritchie, inventor of the Brompton folding bicycle, once said that the perfect portable bike would be “like a magic carpet…You could fold it up and put it into your pocket or handbag”. Then he paused: “But you’ll always be limited by the size of the wheels. And so far no one has invented a folding wheel.”It was a rare — indeed unique — occasion when I was able to put Ritchie right. A 19th-century inventor, William Henry James Grout, did in fact design a folding wheel. His bike, predictably named the Grout Portable, had a frame. that split into two and a larger wheel that could be separated into four pieces. All the bits fitted into Grout’s Wonderful Bag, a leather case.
A. Grout’s aim: to solve the problems of carrying a bike on a train. Now doesn’t that sound familiar? Grout intended to find a way of making a bike small enough for train travel: his bike was a huge beast. And importantly, the design of early bicycles gave him an advantage: in Grout’s day, tyres were solid, which made the business of splitting a wheel into four separate parts relatively simple. You couldn’t do the same with a wheel fitted with a one-piece inflated （充气的） tyre.
B. So, in a 21st-century context, is the idea of the folding wheel dead? It is not. A British design engineer, Duncan Fitzsimons, has developed a wheel that can be squashed into something like a slender ellipse （椭圆）. Throughout, the tyre remains inflated.
C. Will the young Fitzsimons’s folding wheel make it into production? I haven’t the foggiest idea. But his inventiveness shows two things. First, people have been saying for more than a century that bike design has reached its limit, except for gradual advances. It’s as silly a concept now as it was 100 years ago: there’s plenty still to go for. Second, it is in the field of folding bikes that we are seeing the most interesting inventions. You can buy a folding bike for less than £1,000 that can be knocked down so small that it can be carried on a plane — minus wheels, of course — as hand baggage.
D. Folding wheels would make all manner of things possible. Have we yet got the magic carpet of Andrew Ritchie’s imagination? No. But it’s progress.
E. 第14题：We can infer from Paragraph 1 that the Brompton folding bike .
F. was portable
G. had a folding wheel
H. could be put in a pocket
I. looked like a magic carpet
[单选题]假定2009年生产1件某种商品的社会必要劳动时间是20小时，价值用货币表示为2000元，A公司的劳动时间是10小时，产量为10万件。如果2010年生产该种商品的社会劳动生产率提高1倍，A公司的劳动生产率提高50％，则A公司2010年的收入与2009年相比（ ）
A. 增加3000万元
B. 减少5000万元
C. 增加5000万元
D. 不变
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