从蝌蚪发育到青蛙，呼吸器官的变化是[]A．鳔、鳃、肺B．外鳃、肺C．内鳃、肺D．外鳃、内鳃、肺-八年级生物

更多内容推荐

• 两栖类动物的生殖与发育过程（1）两栖类概念：幼体在水中生活，用腮呼吸；成体在潮湿陆地上生活，有时下水，用肺呼吸，皮肤辅助呼吸。（2）蛙的发育经历_______________________四-八年级
• 下图为青蛙的发育过程，请据图回答：(1)青蛙的个体发育起点是[]________。从整个发育过程来看，青蛙的发育属于________。(2)从图中可以看出[]最像鱼，从外形上看像鱼的特点是-八年级生物
• 鱼类受精卵的孵化受水温影响很显著，下列表格和曲线图是某种鱼的受精卵在不同水温中孵化的实验结果：水温（℃）1418222630343842平均孵化率（%）0557092845660请根据图表数据分析回-
• “黄梅时节家家雨，青草池塘处处蛙。”春末夏初，青蛙的叫声此起彼伏。如果寻声找去，你会发现池塘中的青蛙正在抱对；不久后再来，会在水中看到小蝌蚪；如果继续观察下去，会看-八年级生物
• 下面是青蛙变态发育的过程，请将其按正确的顺序排列①尾和鳃逐渐消失，形成肺②同鱼的形态十分相似③长出前肢④长出后肢⑤有尾，也有后肢[]A．①③②④⑤B．④③⑤①②C．②③④⑤①D．②④③⑤①-八年级生物
• 个体发育属于变态发育的是[]A．大鲵B．鲫鱼C．蜥蜴D．蛇-八年级生物
• 蝌蚪用________呼吸，青蛙用________呼吸。-八年级生物
• 下列关于动物生殖和发育方式的描述中，错误的是[]选项生物种类受精方式发育方式A金鱼体外受精体外发育B青蛙体外受精体外发育C家鸡体内受精体外发育D蝴蝶体外受精体外发育-八年级生物
• 两栖动物的幼体一般都生活在______中，成体营________生活。-八年级生物
• ________ the delayed flight will take off depends much on the weather.A．WhyB．WhenC．ThatD．What-英语
• I will carry out the plan _____ there is much difficulty ahead.A．as ifB．even ifC．ifD．unless-高一英语
• 两栖类的代表动物青蛙，其生殖和发育过程包括如下几个阶段：①蛙的卵块；②雌雄蛙抱对；③蝌蚪；④成蛙；⑤雄蛙鸣叫。请指出正确的排列顺序。[]A．⑤④②①③B．②⑤①③④C．⑤②①③④D．②①⑤③④-七年级
• 下列对两栖动物的描述，错误的是[]A．既能生活在水中，又能生活在陆地上的动物是两栖动物B．两栖动物变态发育，幼体为蝌蚪，成体具有四肢C．两栖动物幼体生活在水中，成体一般在-八年级生物
• 青蛙的生殖发育特点是[]A．雌雄同体、体内受精、体内发育B．雌雄同体、体外受精、体外发育C．雌雄异体、体内受精、体内发育D．雌雄异体、体外受精、体外发育-八年级生物
• “黄梅时节家家雨，青草池塘处处蛙。”春末夏处，青蛙“呱、呱、呱”的叫声此起彼伏。如果寻声找去，你会发现池塘中的青蛙正在抱对。不久，如果你再来，会在水中看到小蝌蚪。如果-八年级生物
• 青蛙的变态发育大约经历多少天[]A．30多天B．40多天C．50多天D．60多天-八年级生物
• Please send us all the information _________ you have about the candidate for the position.A．thatB．w
• Half an hour later, Lucy still couldn’t get a taxi _______ the bus had dropped her. A．untilB．whenC．a
• The professor had no sooner finished his speech ________ the students started cheering.A．sinceB．whe
• -What are you going to do this afternoon?-I'll probably go for a walk later on＿＿＿it stays fine．
• （2014年北京市西城区高三5月二模试题）22. ______ Stephon Marbury is an American, he has become a role model among Bei
• 青蛙的生殖方式是[]A．卵生、体内受精B．卵生、体外受精C．胎生、体外受精D．胎生、体内受精-八年级生物
• 每年春末夏初，池塘边传来阵阵蛙鸣，这是雄蛙在[]A．唱歌B．求偶C．捕食D．呼吸-八年级生物
• Cathy had quit her job when her son was born _______ she could stay home and raise her family.A．now
• “Every time you eat a sweet, drink green tea.” This is _____ my mother used to tell me.A．whatB．howC．
• Was it on a lonely island ________ he was saved one month after the boat went down？(2011·四川)A．where
• our manage objects to Tom’s joining the club, we shall accept him as a member. A．UntilB．UnlessC．IfD．
• 下列受精方式属于体外受精的生物是（）A．青蛙B．蟾蜍C．家蚕D．鸡-八年级生物
• I toured the Great Wall，I was deeply impressed with the beautiful scenery．A．For the first timeB．At
• It’s uncertain ____ the fashion show will be held next week.A．whatB．whyC．whetherD．that-高一英语
• ________ parents say and do has a lifelong effect on their children.A．ThatB．WhichC．WhatD．As-英语
• I think _______ impresses me about his painting is the colours he uses.A．whatB．thatC．whichD．who-英语
• （2014年安徽省合肥市高三第三次教学质量检测）28. Let's take a bus or taxi to the park — ______ you'd prefer to
• Choosing the right dictionary depends on ________ you want to use it for.A．whatB．whyC．howD．whether-英
• _______ you start eating in a healthier way, weight control will become much easier.A．UnlessB．Althou
• ________ (assume) that we can't get the necessary equipment, we will have to give up the experi
• The news _____ the spaceship succeeded in returning to the earth spread everywhere.A．thatB．whichC．wh
• Having checked the doors were closed, and ________ all the lights were off, the boy opened the door
• The patient's son asked the doctor the question ________ his father could survive the big opera
• The boss refused to sell the car for ________ he thought was not satisfactory.-高三英语
• —The patient looks much better. ________ is it that has made him ________ he is today?—I think it is
• ---Could you please give the dictionary to Wang Feng?---Yes, of course! I’ll give it to him _______
• Give me a chance, ________ I’ll give you a wonderful surprise.A．ifB．orC．andD．while-英语
• ________ I really don't like art, I find his work impressive.-高三英语
• It is none of your business ________ other people think about you.Believe yourself.A．howB．whatC．whic
• You can only be sure of ________ you have at present; you cannot be sure of something ________ you m
• ____________ your father saw you, what would he say?A. IfB. Suppose C. Unless-英语
• I'm happy ________________ you are happy.A. if B. unless C. as long as-英语
• _________ I am, I will be thinking of you.A. Where B. Wherever C. Who-英语
• I'll be out for some time. ______ anything important happens, call me up immediately.A．In case