(
课件网) Unit 4 Our animal friends 主题范畴： 人与自然 主题群： 环境保护 子主题： 热爱与敬畏自然，与自然和谐共生 Key question Why are animals important to us tell stories about how animals help human beings. explain why animals are important to us. understand the relationship between humans and animals. describe how wild animals became our friends and helpers. Unit objectives 单元目标 I can: Lead-in Do you know some interesting biological science 生物发光：部分生物具备独特的发光能力。比如萤火虫，能在夜间闪烁美丽光芒，这源于其体内荧光素在荧光素酶作用下与氧气发生反应产生光；深海中一些生物，像灯笼鱼、发光水母等，也能发出蓝色等颜色的光，用于吸引猎物、求偶或自我保护等 。 拟态：指一种生物在形态、行为等特征上模拟另一种生物或非生物的现象。例如，枯叶蝶的翅膀形状和颜色酷似枯叶，在遇到危险时能伪装成枯叶躲避天敌；竹节虫身体细长，形态如同竹节，隐藏在树枝间不易被发现。 共生：不同物种之间形成的紧密互利关系。以地衣为例，它是藻类和真菌的共生体，藻类通过光合作用为真菌提供有机物，真菌则为藻类提供水分、无机盐以及保护，使它们能在恶劣环境中生存；还有根瘤菌与豆科植物的共生，根瘤菌能固氮，为植物提供氮素营养，植物为根瘤菌提供生存场所和能量。 变态发育：一些动物在生长发育过程中，形态结构和生活习性会发生显著变化。如青蛙，幼体（蝌蚪）生活在水中，用鳃呼吸，有尾；成体大多生活在陆地上，也可在水中游泳，用肺呼吸，无尾；蝴蝶的发育要经历卵、幼虫（毛毛虫）、蛹和成虫四个阶段，各阶段形态和生活方式差异很大。 Bees are very different from other animals: they live together in huge groups called colonies (群体). Let’s find out more about the life of bees! Read the text about the life cycle of bees. Read the life cycle of bees and answer the question. Task 1 How many types of bees are mentioned in the article What are they Three. They are queen bee, drone and worker bee. drone //dr n/ n. 雄蜂 Read and complete the table. Task 2 This is a queen bee. She is the biggest bee. There is only one queen in a colony. She lays the eggs. Queen bees What do they do (1)_____ They lay the eggs. Drones What do they do (3)_____ This is a drone. Drones are male bees. Their main job is to mate (交配) with the queen. Their main job is to mate with the queen. Worker bees What do they do (5)_____ This is a worker bee. Worker bees are female. They build the colony and they clean it too. They look after the young bees. They make honey with the things they collect from flowers. They build the colony and clean it too. They look after the young bees. They make honey. Read and complete the table. Task 3 Queen bees Development time: (2)_____ Drones Development time: (4)_____ Worker bees Development time: (6)_____ about 16 days about 21 days about 24 days Do you know any other interesting facts about bees Discuss in groups. Unique communication methods: Bees can communicate through dancing. For example, when a honey-bee searches for and inspects a new nest site, it advertises and debates the merits of the new site with a waggle dance. The better the site, the lon ... ...
