Unit 5 Farms and us Part B Let's talk（课件+素材）-2025-2026学年人教PEP版英语四年级下册

Unit5 Farms and us Unit5 Farms and us What can we learn on a farm? What can we learn on a farm? B Let’s talk & Play a guessing game Let's review What can you see on Mr wang’s farm? Farm gives us many things. What else can farm give us? What else can farm give us? Think and say fruit trees beautiful flowers vegetables Look and say Mike is visiting Mr Wang’s farm. What does he see on the farm? What does Mike see on the farm? Watch and answer red tomatoes yellow tomatoes potatoes bee boxes 蜂箱 Read and check What are these? They're tomatoes. But they’re yellow! Yes. A lot of tomatoes are big and red, but these are small and yellow. Good to know Watch and feel Read and check What are those? They're bee boxes. Why does Mr Wang keep bees on his farm? ...... Bees are good for plants. Listen and answer Think and say What can bees give us? 请关注特殊疑问句及并列词语的升降调哦！ Tip Enjoy the video Listen and imitate What are these? They're tomatoes. But they’re yellow! Yes. A lot of tomatoes are big and red, but these are small and yellow. What are those? They're bee boxes. Bees are good for plants. What are these? They're tomatoes. Yes. A lot of tomatoes are big and red, They're bee boxes. Bees are good for plants. What are those? But they’re yellow! but these are small and yellow. Role--play Standards 1.Correctly.表达准确 2.Fluently.表达流畅 3.Confidently.自信大方 --What are those? --They're __________. Look and guess tomatoes pigs chickens apples bananas Look and guess What are these/those? They're ... Play a guessing game What are those? They're ... Pig: Oink Horse: Neigh Cow: Moo Sheep: Baa Chicken: Cluck Duck: Quack Make a dialogue A: Welcom to my farm. B: What are these? A: They’re ________. B: What are those? A: They’re ________. B: How many _____ do you have? A: I have ______. B: I like your farm. Summary What do we learn today? 询问近处有某物： --What are these? --They’re ... 询问远处有某物：--What are those? --They’re ... 1584.0 1704.0 5904.0 1488.0 1920.0 1632.0 1656.0 3600.0 2424.0 $Hi, boys and girls, there are some vegetable les on my farm, such as tomatoes, potatoes and Green beans. Let's come and see. These are good for plants. Yes, a lot of tomatoes are big and red, but these are small and yellow. There b boxes. They are tomatoes. 没熟的番茄是绿色，为什么成熟后却大多变成了红色？这是因为番茄果实中不同色素的含量发生了变化。未成熟的番茄果实主要含有叶绿素，随着它日渐成熟，叶绿素开始降解，被其他色素所取代，其中果肉中积累了红色的番茄红素，而果皮中则积累了黄色的类黄酮，它们会让番茄呈现红色。在变色的过程中，多种基因起到的作用，调控叶绿素降解的SGR1，调控番茄红素和类黄酮合成的CE和mip 12。如果改变这些基因，是不是就意味着番茄的颜色也随之改变？研究人员就通过基因编辑技术定制出了7种不同颜色的番茄。他们将SGR131和mip 12同时敲除，这样就得到了绿色番茄，然后再让这株绿色番茄和正常的红色番茄杂交。第一代杂交番茄仍是红色的，而让他们自交得到的第二代番茄却由于不同基因的自由组合而呈现出了多种色彩，比如没有加一的橙色番茄、没有SGR1和mip 12的红紫色番茄等等，共七种颜色，事实上我们日常生活中早已见过各种颜色的番茄，不过通常来说，要得到不同色彩需要经过许多代的杂交选育，又耗时又费精力。但这次研究则是直接通过基因编辑技术，在一年时间内就定制出了彩色番茄。研究人员发现，这些番茄只是颜色变了，但营养价值、果实的重量和产量都没有显著变化。依靠这种技术，以后不仅有彩色的番茄任你挑选，或许其他蔬菜水果也能定制各种颜色了。 But these are small and yellow. What are these? But they're yellow. Yes, a lot of tomatoes are big and red. What are those?