2022-2023学年上海市嘉定区高二（下）期末英语试卷,以下展示关于2022-2023学年上海市嘉定区高二（下）期末英语试卷的相关内容节选，更多内容请多关注我们

1、2022-2023学年上海市嘉定区高二（下）期末英语试卷一、选词填空-句子（本大题共1小题，共10.0分）1.  A.appearances B.imitating C.distinguish D.isolate E.advantageous F.diverseG.identical H.criterion I.markings J.poisonous K.threateningWhy different species start looking exactly the sameIs it better to stand out from the crowd or be simil

2、ar to the background？For birds，the answer is complicated.While peacocks （孔雀） show off their brightly colored feathers to attract mates and ward off predators （捕食者），other birds find it （1） _ to hide themselves by imitating the looks of other birds. Groups of birds flying together often come from the

3、same species，making it hard to（2） _ one from another.However，some groups of birds including two or more species take on similar （3） _ ，which is an uncommon phenomenon. "They all share random features，like feathers on head or yellow bellies （腹部），which makes them almost （4） _ .You can't reall

4、y tell them apart without looking at their （5） _ ." says Scott Robinson，a famous scholar.His new study suggests（6） _ another bird's appearance is not a coincidence （巧合） but rather an evolutionary method to increase their chances of survival.Looking like a bird from a dominant specter helps

5、reduce attack from other members and appear more （7） _ to potential predators. "In imitation，you often want to look like something because there's an advantage to being that other thing.You want species to think you're（8） _ or low-profitable target" says Rebecca Kimball，a professor

6、 of biology. "In grouping birds，one idea is that this has more to do with a predator's ability to（9） _ a target.When there are a group of birds moving around，it may be easier for predators to identify an individual that has a distinct color pattern." While it may not seem like it at first，imitating other birds is helping to create more（10） _ species.Not only do birds imitate more than one species as they grow up，but their appearance varies over time.(1)(2)(

37.某学生观察洋葱根尖(2n=16)有丝分裂的永久装片,在显微镜下观察到如图细胞,下列有关叙述叙述正确的是A.该细胞处于分裂后期B.该细胞中没有纺锤体C.该细胞含有16条染色体D.该细胞中核DNA数目是染色体的2倍

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