1、Listening:<br>清华幼儿英语1a 2、reading:<div>英文：</div><div>科一：from tadpole to frog</div><div>小蝌蚪找妈妈</div><div>froggy绘本</div><div><br></div><div>中文：</div><div>幼体与成体在形态结构和生活习性上有许多差异，属于变态发育</div><div>青蛙和蟾蜍做了解</div><div>青蛙弗洛格系列</div> 3、video： 4、科普<div>蝌蚪种类</div><div><br><div><br></div></div> <div>青蛙种类：toad and frog<br></div> game1、frog-leap<div>i'm a frog, look at me, i have big eyes and four legs, my hind legs are stronger than the fore legs.</div><div>this is my lilypad, i like to stand on it and have a sunshine bath. some time i will dive into the water and have a bath to make my skin wet.</div><div>i can leap, i'm as fast as an airpalne, will you have a compitition with me, i will win you. croak....</div> game2、蝌蚪水上漂：原理一般白板笔中加入了一种叫做剥离剂的特殊物质，被水冲或被擦拭时，油墨极易与书写面发生脱离，于是画在盘子上的小人画像就容易脱离盘子，并漂浮在水面上。<div><br>Material：<br></div>Whiteboard pen<div>plate</div><div>water</div><div>step:</div><div>draw some tadpoles on the plate, you must put them in the water before they are dry</div><div>look at the tadpols, they float in the air</div><div><br></div><div>拓展“水上漂”</div><div><br>你需要：水碗针纸巾<br><br>这样做：碗里装水，把纸巾放在水面上，在把针平放在纸巾上。纸巾吸满水，沉入水底，针会跟着沉下去吗？<br><br>想一想：为什么针能有“轻功”，在水上漂呢？<br><br>有创意：试一试，利用水的表面张力，还可以托起别的什么东西，比如能托起硬币吗？<br><br>告诉你：水面有表面张力，针可以浮在水面上。<br></div><div><br></div> game3、绘画<div>today, we will draw a pond, the pond is blue, there is lilypads and tadpoles in the water. let use the sponge stamps(海绵印章) to draw the bubles, use the clay to make lilypads and tadpoles.</div><div>tapolse have big head and long fine tail</div> 4、game:折纸青蛙<div>参考：https://www.wikihow.com/Make-an-Origami-Jumping-Frog</div> Folding the Frog’s Front Legs<div>a:Fold the top corners over the center of the paper. The top side of the paper should line up with the left side, forming a triangle shape. Press the fold with your finger to create a crease, then unfold it. Now do the same with the top left corner. Unfold the paper. You've now created a creased "X."</div><div>b:Fold the paper in half. Hold the paper on the table in front of you so that the bottom edge is facing you. Fold the top half of the paper horizontally, so that the two top corners meet the two bottom corners. Seal the fold with your finger, then unfold it. The new crease you've made should cross over the X, creating a pattern that looks like an asterisk or star.</div><div>c:Pinch in the sides to form a triangle. Center the paper on the table so that the bottom edge is facing you. Push the folds of the horizontal crease at the top of the paper toward the center. By pushing these folds inside the paper, the square will collapse into a triangle shape with two sides.<br>To make the two sides fold inwards on themselves more easily, re-fold the horizontal crease you made in the previous step, but in the opposite direction.</div><div>d:Fold one triangle corner upward. Place the triangle on the table so that the long edge is facing you. The long edge of the triangle divides into four points, two on each side. Take the top layer’s corner on the right side and fold it up. The tip of the corner should touch the tip of the triangle. Crease the fold with your finger.</div><div>e:Move the opposite triangle corner upward. Take the top layer corner on the left side of the triangle. Fold it up so that the tip of the corner touches the tip of the triangle. Crease the fold with your finger. The paper should now look like a triangle with a diamond in the middle.</div><div>f:Fold the right corner of the diamond inward. With the base of the triangle facing you, grab the right corner of the diamond. Fold it so the right edge of the diamond lines up with the center line. Crease the fold with your finger.<br>g:Move the left corner of the diamond inward. With the base of the triangle facing you, grab the left corner of the diamond, and fold it inward so that the left edge lines up with the center line. Crease the fold with your finger.</div><div>h:Create the frog's front legs. The point of the triangle, under the diamond layer, is divided into two sides. Fold the right one out, toward the right side of the triangle, so that its edge lines up with the right edge of the diamond. Crease it. Fold the left one out, toward the left side of the triangle, so that its edge lines up with the left edge of the diamond. Crease it.</div> Folding the Frog’s Back Legs<div>a:Flip the paper over. Rest it on the table so that the bottom of the triangle is facing you. The frog is starting to take shape! The front legs should now poke out from underneath at the tip of the triangle.</div><div>b:Fold in the bottom corners. Take the right bottom corner and fold it from the tip of the triangle toward the center, making a vertical line at the center. Crease it. Now fold in the left bottom corner in the same way, so that its edge meets the edge of the other side at the center. You've now created an oblong diamond shape.</div><div>c:Move the inner edges outwards. Fold the right half of the diamond outward, so that its inner edge lines up with its outer edge. Crease the fold. Fold the left half of the diamond outward in the same way, so that the inner edge lines up with the outer edge, and crease it. These newly folded triangles will become the frog’s back legs.</div> Finalizing the Frog<div>a:Fold the frog in half. Position the frog so that the long back legs are facing you, and fold it in half, near where the body is narrowest. Make sure to fold the legs underneath the “body” of the frog. Crease the fold.<br></div><div>b:Make a crease for the frog's back legs. Keep the frog folded in half, with the back legs facing you, and turn it over. Fold the legs upward, so that the horizontal piece of paper that stretches between the legs lines up with the frog's bottom (the fold you made in the previous step). Crease the fold.</div><div>c:Make your frog jump. Set the frog down on its back legs. Press and release the center folds to make it jump. Have fun! These frogs should jump and flip quite well.</div>If your frog isn’t jumping properly, double-check your folds to make sure everything is in the right place. You can also try thicker paper, which usually has more “spring.” 5、ft：生命周期----养青蛙 <div><div>欢迎新朋友2020.5.24，池塘找了一个月也没看到蝌蚪，今天邻居家送了好多，期待成蛙</div><div>蝌蚪喂养的方法：<br>每次给食后残留的饲料，必须用吸管清除出去，并且每隔一两天换一次水。最简便的饵料是面包、饼干的碎屑或碎饭粒，也可以给少量煮熟的蛋黄作为动物性饲料。</div></div><div>1、生长初期（1～10天）：蝌蚪孵出三天内不觅食，依靠从卵黄中带来的营养维持生命，过早喂食反而导致其死亡。三天后蝌蚪的活动量明显增加，两鳃盖完全形成时开始觅食，按每万尾蝌蚪投喂一个蛋黄的标准定时投喂，并适当加入一些水中天然浮游生物，如水蚤、藻类。<br><br>2、生长前期（10～20天）：小蝌蚪10天以后，其食量增大，生长发育加快，开始寻找新的食物，但其消化功能仍然不强，此时饲养的好坏直接影响到蝌蚪的成活率。因此，在饲养上必须补充饵料，以满足其生长发育的需要，主要以营养丰富的糊汁饵料为主，如蛋黄、玉米粉、4号粉，并辅以细嫩的藻类植物等。<br>煮过的菠菜和窝苣是适宜的饲料，但不要煮得过熟，并且要去掉纤维<br><br>3、生长中期（20～50天）：生长中期蝌蚪的消化功能不断增强，为促进蝌蚪消化道的尽快发育，适应两栖类某一特定蝌蚪期“食草性”的生物特性，20日龄后蝌蚪除投饲糊汁饵料外，应投喂植物性饲料和藻类植物，如浮萍。<br><br>4、生长后期（50～78天）：生长后期是蝌蚪转化为幼蛙的关键时期，蝌蚪在此期要长出后肢和前肢，并且由水生转化为水陆两栖。这一时期在饲养上除投饲足够的饲料外，还要添加少量的动物性的活饵饲料。<br></div> <h1><ul><li><font color="#ed2308">egg</font><br></li></ul></h1> <h1><ul><li><font color="#ed2308">tadpole</font></li></ul></h1>feed tadpole with the cooked vegetables and alga<div>alga---a simple, nonflowering, and typically aquatic plant of a large group that includes the seaweeds and many single-celled forms. Algae contain chlorophyll叶绿素 but lack true stems, roots, leaves<br></div><div><br></div><div>we can feed tadpoles with alga and cooked vegetables. when tadpoles live in pond, they eat alga and mosquito babies, they are healthy. now they come to our hourse, we should protect them and feed them, today is sunday, your dady will take you get some algas in the pond, take your bucket and web,let's go</div><div>look at the pond, there are so many tadpols, but they are different with our tadpols, they are black, they will grow up as the toad which has many spots. frog's skin is smothy, but toad's skin is bumty, i don't like toad.</div><div> the toads can eat bugs in the water, just like the mosqito baby live in the water, mostly they will eat algas.</div> external gil for breathing<div>观察呼吸，海鲜市场观察海鲜的呼吸方式，螃蟹，鱼</div><div>蝌蚪呼吸：从水面上吸出一个小气泡。<br>小蝌蚪们在生命之初是靠腮呼吸的，但它们也会发育出肺，并开始到水面附近呼吸空气。尤其是当水中含氧量不太够的时候，这些来自空气的供氧对它们的生存很重要。<br><br>研究者们观察了5个物种的蝌蚪在水面附近呼吸空气的样子，结果发现它们呼吸的动作有点特别。这些小蝌蚪并不是直接把脑袋探到液面的上面，而且贴着液面进行吮吸，吸出一个气泡来，然后再从中挤压出需要的气体提供给肺，最后把多余的气体吐出去。<br><br>为什么不直接探头到液面以上呢？研究者们认为小蝌蚪大概是受到了表面张力的限制。在水的表面张力的作用下，空气与水的交界面会变得有点像是一层弹性薄膜屏障。人类这样个头大的动物几乎不会感受到水面的阻碍作用，但对于尺寸小的物体它的影响会增大很多。在表面张力的作用下，小昆虫可以站立在水面上而不会穿过水面，水生的小生物想穿过水面接触空气也会变得困难。相比之下，可能反而是留在液面下方吮吸气泡更容易一些。<br></div> tail keeps on growing hindlegs appear front legs appear live from food stored in the tail tail becomes shorter <h3></h3><h1><ul><li><font color="#ed2308">young frog-呼吸</font><br></li></ul></h1><font color="#39b54a"> how can you breath?</font><br>i can breath with my lung, a pipe conectes my mouth and nose and lung, lung is like a baloon, when i press the baloon, the air will go out, i exhale, the air goes out from my nose or mouth.<br>when i inhale the air goes into my lung. when i loose my hand, ballon gets bigger. frog has lung, frog can breath with lung, sometime frog will breath with its skin <div><br></div><font color="#39b54a"> 呼吸方式</font><br><div>两栖动物利用三个方式进行气体交换:皮肤,口和肺呼吸(采取吞咽式呼吸--肺进化的不够完善).<br><br>1、尤其当冬天来临他们在冬眠时更是需要用皮肤呼吸.然而即使在正常环境下,肺呼吸正进行时,大部分的二氧化碳由表皮释出,而氧气由肺获取.<br><br>2、青蛙的肺并不发达,仅仅是一对薄壁的囊,构造很简单,气体的交换量也很少,依靠它得到的氧气,不能满足生活上的需要,还得由皮肤呼吸来补足。<br><br>3、青蛙的皮肤经常分泌粘液,保持湿润状态,使外界空气中的氧和皮肤微血管血液中的二氧化碳进行交换,以补充肺呼吸量的不足.青蛙透过皮肤呼吸所得的氧,大约占吸氧总量的40%左右.<div><br></div><div><font color="#39b54a">如何呼吸</font><br></div><div>青蛙虽然像我们人一样也用肺进行呼吸，但却不像我们人一样，让外界的空气进入鼻孔，直接通过气管到达肺部。而是在吸气的时候，把它那宽阔的嘴巴紧紧地闭上，这样口腔底部就下降了，口腔显得增大，外界的空气就通过鼻孔吸入口里，使口腔装满空气。接着它又闭上鼻孔，同时让口腔底部的肌肉收缩，使口腔底部上升，这样口腔就显得变小了，压迫着口腔里的空气通过喉头进到肺里去。<br><br>然后它又让腹部的肌肉收缩，并依靠肺壁的弹力，把肺里的气体又压回到口腔里。这样的动作要反复好多次，使气体进行了充分的交换之后，青蛙又一次通过鼻孔，把口腔的气体压到体外去。这样，青蛙的口底就不停地一鼓一鼓，好象我们人一样，呼吸时胸部会一起一伏。<br></div></div> <div><font color="#39b54a">为什么青蛙要保持皮肤湿润</font><br></div>由于皮肤裸露，不能有效地防止体内水分的蒸发，因此它们一生离不开水或潮湿的环境，怕干旱和寒冷。所以大部分生活在热带和温带多雨地区，分布在寒带的种类极少。