叶片与外界环境之间进行气体交换以及水分散失的“门户”是[]A．表皮B．气孔C．保卫细胞D．叶脉-七年级生物

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• 植物叶片与外界环境之间进行气体交换的门户是[]A．气孔B．角质层C．表皮D．保卫细胞-七年级生物
• 关于叶片的结构和功能特点正确的是[]A．植物叶片上的气孔都分布在下表皮B．植物的蒸腾作用能促进植物体从土壤中吸收水分和无机盐C．夏日的正午蒸腾作用减弱，主要原因是保卫细胞-八年级生物
• —We were surprised to hear that the reason________ she gave for her absence was________ her mother w
• (2013·高考安徽卷)It’s said that the power plant is now ________ large as what it was.A．twice asB．as twice
• (2013·高考陕西卷)Let those in need________that we will go all out to help them.A．to understandB．understan
• 读图回答下列问题：（1）植物蒸腾作用的主要器官是__________。（2）图中③是________，有输导和支持的作用，⑥是________，它是气体交换的窗口。（3）⑧是__________，内含
• -I'm sorry I'm late again But I…．-It's 'no use_______. It's the third time
• 绿色植物叶片的主要功能是[]A．吸收水分，运输有机物B．制造有机物，蒸腾水分C．贮藏有机物，产生二氧化碳D．运输有机物和无机盐-七年级生物
• Our neighbor has ________ ours.A．as a big house asB．as big a house asC．the same big house asD．a hous
• 观察下图，回答下列问题。(1)上图是_________的展示图，其结构名称分别是：①____，②____，③_________，④_________。(2)①的形状_________排列，______
• —________ no ad during TV plays.—Great move! I cannot tolerate those annoying ads appearing every se
• As far as I am concerned，education is about learning and the more you learn，________.A．the more for
• -I've left my watch in the hotel. -I ______ and get it for youA．goB．am goingC．am to goD．will go
• 叶的下列结构中，能进行光合作用的是[]A．表皮B．气孔C．导管D．叶肉-七年级生物
• 绿色植物的叶片一般包括________、________和________三部分，叶的表皮细胞外壁上有一层_______，它可以保护叶片________________，并防止____________
• 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
• 下图是叶片结构模式图，请回答下列问题。（前面4空填标号）(1)对叶片起保护作用的结构是_________。(2)叶片对外界进行气体交换是通过_________实现的。(3)能够输导水和无机盐的-七年级
• 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．