<b> 3a-unit 3 Plants 拓展 part2</b><div>今日繼續(xù)補充，種子結(jié)構(gòu)，種子如何傳播，植物與人類</div><div><b>? Parts of a Seed：Germinating Seeds<br>? How Do Seeds Spread?<br>? Plants Habitat</b><br></div><div><b>? Plants and human<br></b></div> 第2部分的海報，這次主要是帶著Eric一起來學(xué)習(xí)。 一起了解完種子的構(gòu)成之后用橡皮泥來制作屬于自己的種子吧，Eric的embryo有一片葉子且是肥大的葉子，這顆種子注定是個胖寶寶。 把家里能找到的豆子都找出來一起看看都有哪些。 看圖找豆子之匹配游戲。 一起“種”下種子，等待發(fā)芽。 種子傳播的幾種方式，不難理解，Eric基本都能get到。 <div>Everything on earth has a life cycle. Life begins, it grows, it reproduces, it dies. But what is a plants life cycle? Plants start their lives as tiny seeds.<b><br></b></div><b>(1) Parts of a Seed</b><br><div>A seed is like an egg. It is where a baby plant starts its life. Seeds are found in flowers and fruit. They come in many shapes and sizes. When a fruit falls to the ground, its seeds drop into the soil. Rain helps by pushing the seeds all the way into the soil. Once a seed is in the soil, the baby plant will burst out of its outer seed coat and begin to grow!<br></div> <br><div><ul><li>Inside is an embryo, which is a tiny plant and the endosperm, which are small leaves. The embryo is surrounded by a food storage area. All seeds have a protective outer layer called the seed coat, just like an eggshell.<br></li><li>Once the baby seed grows out of its coat, it's called a seedling. Then the baby seed grows roots to get minerals and water from the soil. As its stems grow, it also sprouts leaves, which will allow it to make its own food from sunlight. The adult plant will grow out flowers and fruits to spread more seeds and start the plant life cycle again.<br></li></ul></div><div>Seeds can be as tiny as a grain or as big as a fingernail. Some are round while others are flat or tear-shaped.<br></div><div><b>Types of nuts and seeds</b></div> <b>Types of beans</b> <b>Experiment: Germinating Seeds</b><br>Seeds are baby plants. They have a thick, hard coat on them, just like a baby chick inside an egg. When conditions are right—good light, warm temperature, and moisture—the seedling comes out! In this activity, you'll germinate some seeds and watch as they grow into full size plants. <b>(2) How do Seeds Spread?</b><div>Plants spread their seeds in several ways.<b><br></b><div><ul><li><b>Wind: </b>Many, like the dandelion,have flying or drifting seeds that depend on the wind to carry them through the air.</li><li><b>Drop</b>: Other plants have exploding seed pods that fling seeds into the air.</li><li><b>Animals:</b> Many seeds are contained inside tasty fruits, including nuts and berries.These get eaten by hungry birds and other small animals.The seeds then get dispersed through the animal's droppings. Some seeds are attached to animal fur and get carried away.</li><li><b>Water: </b>Some water plants, such as lotuses and lilies, let their seeds fall on the water and float away.</li></ul></div></div> <b>(3) Plants habitat</b><br>There are around 300, 000 - 315, 000 types of plants in the world, most of them are seed plants.<br>Some types of plants we know are, trees, shrubs, grass, vines, ferns and mosses.<br> <br>Everything that is living needs a home. A plant is a living thing. Plants grow. They need water, sunlight and soil to live and grow properly. For a plant to grow like it is supposed to it needs to live where they can get what they need.<div><ul><li><b>Rain forest </b>is a hot,wet place where there are many tall trees.Many plants have large,pointy leaves.</li><li><b>Grassland </b>is a dry place with a lot of grass. Grassland plants roots are deep to stay alive.</li><li><b>Fresh water</b> has very little to salt. Fresh water plants leaves and flowers float on top of water.</li><li><b>Ocean</b> is a very large and deep body of salty water. Ocean plants are soft, their leaves and root need the sunlight and minerals.</li><li><b>Desert </b>is dry, many desert are hot, there is little rainfall. Desert plants keep water in their stems.</li><li><b>Arctic</b> is an icy and cold place near the north pole. Arctic plants are small with shallow roots.</li></ul></div> <div><b>(4) Plants and human</b><br></div> We get Food and oxygen from plants. The house is made from many different plant parts. <div>Wood makes a good fuel for cooking.</div> Cotton and linen both come from plants.<div>Some people use herbs to treat common illnesses.</div> Baskets, papers, latex are all from plants. 最后，強調(diào)保護植物保護地球的重要性。