能量流动和物质循环是生态系统的两个密切相关、不可分割的过程。[]-八年级生物

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• 下图是自然界碳循环的简图，图中甲、乙、丙各代表[]A．生产者、分解者、消费者B．消费者、分解者、生产者C．分解者、生产者、消费者D．生产者、消费者、分解者-八年级生物
• If I went to the moon,I _____ bring something unusual back to school.[ ]A.willB. canC. wouldD. shall
• 在“草→昆虫→食虫鸟→鹰”这条食物链中，全部昆虫消耗的能量比全部狼所消耗的能量[]A．多B．少C．相等D．大约相等-八年级生物
• —Could I use your pen? —Of course, you _______.[ ]A. must B. may C. can -九年级英语
• 在生态系统的碳循环中，二氧化碳进入生物体内是通过[]A．呼吸作用B．光合作用C．蒸腾作用D．扩散作用-八年级生物
• —Let's go to the movies tonight.—Sorry.I__ . I have to help my mother wash clothes.[ ]A. mustn&
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• 古书《说苑．正谏》中有这样一段记载：“园中有树，其上有蝉，蝉高居悲呜，饮露，不知螳螂在其后也；螳螂委身曲附欲取蝉，而不知黄雀在其傍也；……”这是比喻社会现象的寓言，但却反-八年级生物
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• 在生态系统中，能量流动的起点是[]A．从生产者固定太阳能开始B．阳光照射到绿色动植物体上时C．生产者被动物所食时D．分解者分解动植物遗体时-八年级生物
• Return home quickly. Your parents _____ be worried about you now.[ ]A. canB. may C. must D. could-九年
• 下图是有关生态系统中碳循环的示意图，请分析回答下列问题。（1）写出①②③④的生理过程及⑤产生C02的方式：①_________、②_________、③_________、④_________、⑤__
• 小华同学说：“爷爷讲在他小时候，村边的小河里有许多鱼、虾，稻田中有不少黄鳝和泥鳅。现在河里和稻田中几乎没有鱼、虾了。”这是什么原因呢？（1）请对上述情况做出假设：_______-八年级生物
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• 下图是珠江三角洲的农民充分利用自然条件，建立的该地特有的蔗基鱼塘和桑基鱼塘示意图。请据图回答：（1）这种人工生态系统最基本的生物因素是___________。要使它长期稳定发展-八年级生物
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• 一般地说，在输入到一个营养级的能量中，只有的能量能流入下一个营养级。-八年级生物
• 在生态系统内，与碳循环始终结合在一起进行的是[]A．氮循环B．水循环C．能量流动D．能量循环-八年级生物
• —Would you like to see Beijing Opera with me tonight?—I'd like to, but I'm afraid I ______
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• 从物质循环的观点看，生物体内碳元素的最终来源是[]A．食物所含有机物中的碳B．非生物界中的碳酸盐C．大气中的二氧化碳D．生态系统中的生产者-八年级生物
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