《The life cycle of the tadpole》
During the tadpole stage of the life cycle the tadpole breathes by means of autonomous external or internal gills. It does not have arms or legs or reproductive organs until later stages in its life, and has a finned tail with which it swims by lateral undulation, similar to most fish. As a tadpole matures, it metamorphoses by gradually growing limbs and then (in the case of frogs) absorbing its tail by apoptosis. Lungs develop around the time of leg development, and a tadpole late in development will often swim to the surface of the water to breathe air. During the final stages of external metamorphosis, the tadpole's mouth must change from a small round mouth at the front of the head, to a large mouth the same width as the head. The intestine will shorten to accommodate the frog's carnivorous diet.
青蛙英语怎么说
古时写作"科斗",是蛙、蟾蜍、蝾螈、鲵等两栖类动物的幼体，又称蛤蟆蛋蛋。刚孵化出来的蝌蚪，身体呈纺锤形，无四肢、口和内鳃，生有侧扁的长尾，头部两侧生有分枝的外鳃，吸附在水草上，靠体内残存的卵黄供给营养。以群居为主。当蝌蚪成熟了，它们开始脱变，渐渐长出四肢，然后(对于蛙和蟾蜍)则透过细胞凋亡(控制细胞死亡)逐渐退化了它们的尾巴。
生长初期：（1～10天）小蝌蚪孵化后3天内不求食，依靠卵黄带来的营养来维持生命。过早喂食反而会导致死亡。
3天后，蝌蚪的活动量明显增加，腮盖完全形成的时候开始寻找食物，按照每万蚪的标准定时喂食蛋黄，适当添加水中的自然浮游生物，如凿子藻类。新孵化的小蝌蚪身体虚弱，对外界环境敏感，尤其是水温、水质和光照。经过10天的生长发育，小蝌蚪的体长可以长到1~1.5厘米。
生长前期：（10～20天）小蝌蚪10天后，食量增加，生长发育加快。小蝌蚪开始寻找新的食物，但消化功能还不强。经过精心饲养，蝌蚪到20日龄时，体长可达2厘米，体色为淡棕色，背部有乳白色图案，尾部边界有明显的黑色v形图案。
中期成长：(20~50d)此时蝌蚪的消化功能越来越强，为促进蝌蚪消化道的快速发展，适应了两栖类特定蝌蚪时期的草生物特征。
生长期：(50~78天)这个时期是蝌蚪变成青蛙的重要时期，蝌蚪在这个时期生长后肢和前肢，从水生变成水陆两栖。大50岁，身体长4cm以上，后肢生长，后肢生长约2周(65岁)，前肢生长，后尾部开始吸收，此时青蛙蝌蚪停止寻找食物进入变态期。
扩展数据：蝌蚪(英语：tadpole)古代写的科斗是青蛙、蟾蜍的幼体，也称为蟾蜍蛋。刚孵化出来的蝌蚪，身体是纺锤形的，没有四肢、嘴和腮，有侧扁的长尾，头两侧有分枝的腮，吸附在水草上，体内残留的卵黄提供营养。以群居为中心。蝌蚪成熟后，开始脱落，四肢逐渐生长，然后通过细胞凋亡(控制细胞死亡)逐渐退化尾巴。
在自然条件下，雌蛙的总产卵量可达5000枚左右，孵化率约为50%，蝌蚪的存活率仅为20%~30%。在人工饲养条件下，小蝌蚪通常在母蛙产卵后人工孵化8-15天。
新孵化的小蝌蚪体呈棕**，体长6~8mm，头部有马蹄形吸盘，用于附着，口位于吸盘下，体弱多病，活动少，通过卵黄囊提供营养，不开口摄食，3天后，可投喂外源营养物质，满足其营养需求和生长需求。小蝌蚪培育的最佳温度为23~25℃，适合pH在6~8℃之间，生长缓慢，从小蝌蚪变态到幼蛙大约需要60~80天，一般分为初期、初期、中期和后期，小蝌蚪对营养的需求各不相同。
青蛙属于脊索动物门、两栖纲、无尾目、蛙科的两栖类动物，成体无尾，卵产于水中，体外受精，孵化成蝌蚪，用鳃呼吸，经过变异，成体主要用肺呼吸，兼用皮肤呼吸。那么，你知道青蛙的英语怎么说吗?
青蛙的英文释义：
frog
Dutch nightingale
青蛙的英文例句：
青蛙和蝾螈都是两栖动物。
Frogs and newts are amphibians.
魔术 师把青蛙变成了公主。
The magician transformed the frog into a princess.
青蛙英语怎么说
蝌蚪是青蛙的幼年形态。
Tadpoles are the infancy form of frogs.
青蛙跳进了沟里。
The frog jumped into the ditch.
你还记得我们解剖青蛙的那堂课吗?
Do you remember the lesson on the anatomy of a frog?
*青蛙青蛙被称作两栖类,因为它们可以生活在水里也可以生活在陆地。
Frogs are called amphibians because they can stay both in water and on land.
蟾蜍的腿比青蛙短，而且通常比青蛙丑。
Toads have shorter legs and are generally clumsier than frogs.
最后，除了这只小青蛙之外，所有的小青蛙都放弃向塔顶攀爬。
At the end everyone else had given up climbing the tower.
蟾蜍比青蛙脚短,一般说来没有青蛙灵活。
Toads have shorter legs and are generally more clumsy than frogs.
这个蝌蚪已长成青蛙。
The tadpole has become a frog.
青蛙在洼地里砰砰跳着。
The frogs plunked in the hollow.
一下雨青蛙就开始呱呱地叫起来。
Frogs began to croak with the rainfall.
蝌蚪会变成青蛙。
A tadpole metamorphoses into a frog.
再一次地，上面的那群青蛙对他喊叫，?别那么痛苦地尝试了，死了算了。?
once again, the crowd of frogs yelled at him to stop the pain and just die.
她真的很害怕这只冰冷的青蛙。
She was really of the cold frog.
她真的很害怕这只冰冷的青蛙。
She was really afraid of the cold frog.
我真的宁愿是一只青蛙，请把我变回去吧。
I?d really rather be a frog. Please change me back!
跳进湖里，和我的孩子在附近 游泳 ，向他们展示那些臭虫，青蛙和小动物，给他们摘草莓。
Jump in the lake, swim around with the kids, show them the bugs and frogs andcritters, pick raspberries with them.
她回答说：?哦，我会给你任何东西，亲爱的青蛙。
"Oh, I will give you anything, dear frog, " she replied.
一只青蛙和一只松鼠是邻居。
A frog and a squirrel were neighbors.
对女人而言，她的爱可以让一只青蛙变成一位英俊的男性，而对男人来说，他的爱则把女人降低为了精神分析所谓的?部分客体?，在你身上使我欲望你的东西。
For the woman, her love can turn a frog into a beautiful man, while for the manlove reduces the woman to what psychoanalysis calls a "partial object", that in youwhich makes me desire you.
所有的青蛙在一块石头边上排起了队来 潜水 。
All the frogs line up on the edge of a rock to dive.
然后，所有的青蛙悲伤地跳走了。
Then,all the frogs hopped sadly away.
野生动物、昆虫、青蛙、鸟类和土壤生物能够在生态环境的织锦中扮演他们的角色，而我们可以做好我们的事情，两者不受干涉或不需妥协。
Wildlife, insects, frogs, birds, and soil organisms are able to play their roles in thetapestry of ecology, and we are able to play ours, without interference orcompromise.
她四处看了一下，看到了一只青蛙，它那肥厚而又丑陋的脑袋正伸出水面。
She looked around and saw a frog. He was stretching his thick ugly head out of the water.
暴雨接踵而来，青蛙也从泥泞中跳出?这正是我们的候选人登场的时候!
Then the rainstorm comes, and the frogs come out of the mud?and they?re ourcandidates!
你还记得那次你妈妈在浴缸里发现那些青蛙的事吗?
Remember that time your mom found those frog in the bathtub ?
为了验证它，我不得不用一只活的青蛙做了试验，但是预想的结果并未发生。
To prove it I?d have to cook a live frog and that?s not going to happen.
马里恩死死盯着我，好像从我眼里爬出一只青蛙似的。
Marion looked at me as if I had a frog crawling out of my eye.
