在显微镜下观察用碘液染色的洋葱表皮细胞时，细胞染色最深的结构是[]A．细胞壁B．细胞膜C．细胞核D．细胞质-七年级生物

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• 将下面植物细胞的结构与相适应的功能用直线连接起来。①细胞壁A．保护细胞内部结构和维持细胞形态②细胞质B．控制细胞内外物质的进出③线粒体C．进行生命活动的重要场所④细胞膜D．能-七年级生物
• 阅读理解。 The kids at the top of the class get there by mastering (掌握) a few good ways that others can l
• 植物体内长成的细胞中，细胞里有[]A．一个大液泡B．许多大液泡C．一个小液泡D．许多小液泡-七年级生物
• 阅读理解。 A teacher from America visited a school in China. In one class, she watched sixty children lea
• 下图是植物细胞与动物细胞示意图，请据图作答：（1）植物细胞示意图是_____图，你的判断依据是该细胞有___________。（任写一项）（2）图中②④⑥是动植物细胞都有的结构，其中④的名称-七年级生
• 将名词与相应的功能对应起来。1．循环系统a．保护内部柔嫩部分2．细胞膜b．使光能变成化学能3．叶绿体c．控制物质进出4．上皮组织d．运输体内物质5．分生组织e．运输水和无机盐6．输导组-七年级生物
• 阅读下面的短文, 完成下面的任务。 A new study finds people in big cities walking faster than before. Is the pace (节奏
• 阅读理解。 Which of your hands do you use most? Very few of us use both of our hands well. Most of us are
• 阅读理解。 You may feel curious (好奇的) about students in other countries: Do they also have so much homewo
• 阅读理解。 Are you carrying too much on your back at school? You're not alone. Back experts (专家) in
• 阅读理解。 "How can I learn English well?" This is a question many students ask. In my opinion,
• 在普通光学显微镜下不易看清植物细胞的[]A．叶绿体B．细胞膜C．细胞壁D．细胞核-七年级生物
• 观察洋葱表皮细胞结构的实验步骤是[]A．制作标本、染色、画图、观察B．制作标本、观察、染色、画图C．染色、制作标本、观察、画图D．制作标本、染色、观察、画图-七年级生物
• 番茄中带有酸味的物质存在于[]A．细胞核B．细胞质C．液泡D．细胞壁-七年级生物
• 植物体中能把光能转化成化学能的结构是[]A．液泡B．线粒体C．叶绿体D．细胞壁-七年级生物
• 阅读理解。 The idea of daylight saving time started with an American named Benjamin Franklin (1706-1790).
• 阅读理解。 Now you've finished three years of English study. There's one way to demonstrate (展示
• 阅读理解。 Today people can use the phone to talk with others almost anywhere on earth. But when you use
• 阅读理解。 The Year of the Dog has gone and this year we have pigs. What words can we think of for pigs?
• 阅读理解。 Dr. Irene Pepperberg, a scientist at the University of Arizona, has worked with Alex for ninet
• 下图是植物细胞平面结构模式图，请据图回答。（1）图中[1]细胞壁的功能是____________细胞。（2）在光学显微镜下不易看到的结构是[]_________，它是保证细胞正常生活的一道屏障，-七年
• 生活在海水中的海带，其细胞中积累碘的浓度比海水中的浓度要高许多倍，而海带细胞仍能从海水中吸收碘，这一事实说明[]A．海带细胞的细胞壁有吸附碘的功能B．海带细胞的细胞质中-七年级生物
• 在植物细胞中，对细胞起保护和支持作用的是________，起控制物质进出的结构是________，细胞核中含有________物质，具有甜味和酸味的物质存在于________中。-七年级生物
• 下列细胞中有细胞壁的[]A．肌肉细胞B．番茄果肉细胞C．血细胞D．神经细胞-七年级生物
• 阅读理解。 WHY IS THE SUN IMPORTANT? The sun is a huge, hot, bright star. It is important because withou
• 完形填空。 Some years ago, Chinese high school students would show their new schoolbags, new clothes or n
• 切西瓜时流出的汁液是[]A．水B．细胞液C．细胞质D．糖水-七年级生物
• 阅读理解。 The spider is very little and clever. Its body is made up of two parts. It has four pairs of l
• 阅读理解。 All students need to have good study habits. When you have good study habits, you can learn th
• 能将光能转变成化学能，储存在它所制造的有机物中的能量转换器是[]A．叶绿体B．线粒体C．DNA和基因D．DNA和蛋白质-七年级生物
• 阅读理解。1. Before China, how many countries had already sent their astronauts into space? A. Only one.
• 完形填空。 There are four kinds of satellites. The first kind of satellite studies the1 of the earth. The
• 小草幼茎是绿色的，是因为茎的皮层细胞中含有[]A．线粒体B．叶绿体C．液泡D．细胞壁-六年级生物
• 阅读理解。 There are over 800 boarding (寄宿) schools in the United Kingdom with students from home and for
• Cloze test. Now, people use satellites (卫星) to do many things. So far, man has invented four kinds o
• 阅读理解。 We all dream although we remember only a few of our dreams. Some people train themselves to re
• 阅读理解。Thumbs Down to Texting 屈指发短信Do you have a mobile phone? Do you send text messages to your frien
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• 阅读理解。 Is it hard for you to get up early and get ready for classes? Some students at Winter Park Hig
• “停车坐爱枫林晚，霜叶红于二月花”，从细胞知识看，引起枫叶颜色变化的物质存在于哪种结构中[]A．叶绿体B．细胞核C．液泡D．细胞-七年级生物
• 下图是植物细胞结构模式图，请填写图中各部分名称：①__________②__________③_________④_________⑤_________-七年级生物
• 下图是一个细胞的结构图。（“[]”内填标号，“_____”上填文字）（1）这是一个________细胞（填植物或动物），其依据是细胞中有[]。（2）如果去掉[]_________，细胞的形态会发生改变
• 阅读理解。 Is it time to get MP3?Your computer has been playing music for years, one CD at a time. Now hu
• 阅读下面短文，按照句子结构的语法性和上下文连贯的要求，在空格处填人一个适当的词或使用括号中词语的正确形式填空。 The two-way radio is very1______ (use) to pe
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• 吃柿子时总会感到有点涩，这是因为它含有单宁，这种物质它存在于细胞的[]A．细胞核B．细胞壁C．细胞膜D．液泡-七年级生物
• 阅读理解。 Penguins lie together, but each pair has a little piece of ground of their own. When a penguin
• 阅读理解。 Imagine this: a television screen has the size and thickness of a piece of paper. You carry it
• 下图是细胞结构模式图，请按图回答以下问题：（1）对细胞起_______作用的是[①]细胞壁。（2）保护细胞并控制物质进出的是[]___________。（3）是细胞进行生命活动的重要场所的是[]__-
• 阅读理解。 "USA? Britain? Which country is better to study in?" We often hear such discussions.