叶脉是叶片的“________”，有________作用，其内还有________和________（输送有机养料），因此，叶脉还有________作用。-七年级生物

更多内容推荐

• In recent years travel companies have succeeded in selling us the idea that the further we go, _____
• With the help of the high technology, this year the factory has produced ________ it did last year.
• 植物体吸收水分的主要部位，运输水分的通道以及水分散失的“门户”依次是[]A．气孔、导管、根毛B．根毛、气孔、导管C．根毛、导管、气孔D．导管、气孔、根毛-七年级生物
• 在叶的结构中，保卫细胞存在于[]A．表皮B．栅栏层C．海绵层D．叶脉-七年级生物
• (2013·厦门质检)Hardly ________ twelve when they realized that it was too late to catch the last train.A．
• 下列物质进入植物体内不需要通过气孔的是[]A．水蒸气B．氧气C．二氧化碳D．无机盐-七年级生物
• ---The manager finally agreed to our new marketing proposals. ---It never occurred to me you could
• 下列四种细胞中为死细胞的是[]A．导管B．叶表皮的细胞C．筛管D．根毛细胞-七年级生物
• 叶肉由许多_________组成，细胞内部的许多绿色颗粒结构是____，____中含有_________等多种色素，它是_________的场合。-七年级生物
• He was________rude________she refused to reply.A．so；thatB．very；thatC．too；thatD．such；that-英语
• Transit, a car made in Jiangxi Province, was sold nearly 50 000 units in 2012, with the total value
• 叶肉栅栏层的特点是[]A．细胞圆柱形，排列疏松，含叶绿体多B．细胞圆柱形，排列整齐，含叶绿体多C．细胞形状不规则，排列疏松，含叶绿体少D．细胞形状不规则，排列整齐，含叶绿体-七年级生物
• AIDS is said_______ the biggest health challenge to both men and women in the earth over the past f
• _______是植物蒸腾失水的“门户”，也是气体交换的“窗口”，它的开闭可由___________控制。-七年级生物
• Kimi is ________ that everyone wants to play with him.A．such lovely a boyB．so a lovely boyC．a such
• 叶脉的功能是[]A．气体通道B．支持和输导C．专用于输导有机物D．专用于输导水分和无机盐-七年级生物
• 下列对气孔的描述中，错误的一项是[]A．气孔是一对保卫细胞之间的孔隙B．气孔的开闭，由保卫细胞控制C．气孔只有下表皮具有，上表皮没有D．气孔是叶片与外界进行气体交换的门户-七年级生物
• —What is the new bridge like?—Well，it is now________of the old one.A．more than the width twiceB．more
• What a table! I've never seen such a thing before. It is ________ it is long.A．half not as wid
• This classroom is __________ that one.A．three times bigger asB．three times as bigC．three times the
• This is the last time I ______ Shanghai. I still remember the first time I ______ there was in 2005.
• 在植物叶片横切面模式图中，D是________，E是_________。-七年级生物
• Mum likes this old house in downtown better than the huge one in the country, but it costs almost .A
• Nowadays we take___ exercise a day as we need because of widely used automobiles.A．less than halfB．l
• Jack has been working hard and _____ is no doubt that he will do a good job in the entrance exam. A．
• ______ your teacher the problem with learning, theoretically, and they will help you.A．TellingB．To t
• We should give the disabled encouragement to live _____ as we do．A．as a rich and full lifeB．as rich
• — What impresses you most about your hometown?— The street, the length of which is four times ______
• 下图为气孔结构图，请据图回答问题（1）其中图A表示气孔_______，图B表示气孔______（2）填出图A中各部分名称①__________②_______③_______（3）气孔的张开和闭和主要
• 在观察叶片的下表皮永久装片时，看到的有叶绿体的细胞是[]A．保卫细胞B．上表皮细胞C．保卫细胞和表皮细胞D．下表皮细胞-七年级生物
• 对气孔的描述不正确的是[]A．是植物蒸腾失水的“门户”B．气体交换的“窗口”C．是由一对半月形的细胞围成的空腔D．白天闭合，晚上张开-七年级生物
• The house rent is high. I've got about half the space I had at home and I'm paying ______
• ----- What a beautiful day! ----- Yes, it’s _____ that I’d like to take a walk.A．too nice weatherB．
• (2012·陕西高考)I ________ thank you too much for all your help to my son while we were away from home.A．
• ________him that she would fail as she was so able and worked so hard.A．It never occurred toB．That
• I _____ the truth of your remarks, although they go against my interests.A．cannot but admitB．cannot
• —How many times have you been to China? —In fact, it is the first time I __________ here.A．have been
• Do you have any idea when the project will be carried out?—No, but I have heard that it was not unt
• _______ is no possibility________ the engineer can complete the project within two weeks.A．There; th
• 截几何图形（a）用刀将马铃薯、萝卜等切出正方体、长方体、圆柱、圆锥、圆台．（b）用刀出截正方体、长方体、圆柱、圆柱．讨论：（1）的截面各有几种形状？（2）截面是圆的几何体有哪些？-七年级数学
• is no need.A．It; complainingB．That; complainingC．There; to complainD．This; to complain-高三英语
• 用平面截一个正方体，可能截出的边数最多的多边形是[]A．七边形B．六边形C．五边形D．四边形-七年级数学
• .Much__________he has a good taste, he can’t avoid being influenced by advertisements.A．that he clai
• _____ playing dumb with teachers. They know very well their students.A．It’s no useB．There is no dou
• 下图为一个三棱柱，用一个平面去截这个三棱柱，截面形状可能为下图中的（）（填序号）．-七年级数学
• ，please start the work tomorrow.A．If you are convenientB．If it is convenient for youC．If it is conve
• Both she and her friends liked travelling. She traveled a great deal, ________.A．nor did most of her
• It is almost five years_______ we saw each other last time.A．beforeB．sinceC．forD．when-高二英语
• ---I had practiced my spoken English, but still failed in the oral test. ---Don’t be discouraged. __
• ______for a long time, but he tried his best to make up for what he missed.A．Being ill staying in ho