高中英語(yǔ) Unit 4 Exploring plants Listening exercise課件 新人教版選修9

Unit 4 Exploring plantsListen to the text.UNUSUAL PLANTSListen to Mark (M), Gordon (G) and Andrea (A) telling their class and their teacher (TH) about some plants.Listen again and fill in the blanks.TH: Today Mark, Gordon and Andrea are going to tell us about some _ plants. Mark, do you want to go first?M: Sure. Today, I want to _ _ an insect-eating plant called a pitcher plant. unusualtalk aboutHeres a _ of it. Look at this part here. Its _ like a pitcher. Its actually a leaf _ _ it looks like a flower. Its really clever - the insects _ _ _ the sweet smell coming from what they think is a flower. But its a _. photoshapedeven thoughare attracted bytrapOnce an insect goes down into the pitcher, it cant get out as there are small hard hairs pointing _ that prevent it from _. In the end, the insect falls down into a pool of liquid at the _ of the pitcher and gets digested by the plant.downwardsescapingbottomS1: Thats _!S2: What _ plants!TH: Gordon.G: These are the plants Im going to talk about. Theyre often called “l(fā)iving stones”, but even though they do look _ _ like stones, they are in fact plants.amazingfantastica bitS3: Wow!S4: How interesting!G: Their _ name is Lithops and they come from South Africa and Namibia. The body of a lithops is actually a pair of _ that have become _ like a stone. This is because this plant lives in very _scientificleavesroundedhotand dry places. When the leaves are _ like this, not much water is lost from the plant. Another interesting thing about these _ plants is that theyre the same colour and _ of the soil and stones around it. This makes them less _ to animals looking for food.shapedstrangeappearanceobviousTH: Thanks, Gordon. Andrea.A: Im going to tell you _ Rafflesia arnoldii, a plant that has a flower about one metre _. In fact, its the _ flower in the world. Rafflesia arnoldii doesnt have any leaves, _ or _. It doesnt need them as its a parasite. It gets its food byaboutwidelargeststemsroots living on another plant. You might think that this flower should smell _ but it actually looks and smells like rotting meat!S2: Oh, yuck!S1: Thats _!S3: I think its fantastic!wonderfuldisgustingA: Me too. _, it _ insects that eat dead animals but _ _ getting a feed, the insects _ _ its pollen and _ it to other Rafflesias, Rafflesia arnoldii grows in the jungles in Indonesia but as the forests are being _ _, its becoming very _.Anywayattractsinstead ofpick upspreadcut downrareTH: Thanks Andrea and thanks everyone. Those plants are certainly fascinating.Listen to the text.THE DESTRUCTION OF TROPICAL RAINFORESTSEd Walker (E) is interviewing Dr Anne Butler (A) about the destruction of tropical rainforests.Listen again and fill in the blanks.E: Anne, we hear a lot these days about how _ tropical rainforests are _.A: Yes, thats right. Rainforests now _ only 6% of the earths land surface. They used to cover about _, so more than half of the worlds tropical rainforests havequicklydisappearingcover14% been _, and thats in less than 50 years. _ 150 acres of rainforest is lost every minute in Asia, Africa, Central and South America.E: Thats _.destroyedOverunbelievableA: Yes, its _. The last _ rainforests could be gone in less than 40 years.E: But why is this happening?A: Well, there are _ _ _ reasons. As populations increase, people need more land to _ _. Forests are cut down to plant crops or to start farms. frighteningremaininga number oflive on The wood is sold for firewood or building materials, furniture and paper, _ _. And there are also mining companies which destroy the forests in their search _ minerals.E: I _ people have to make a living.for exampleforsupposeA: Yes, but you know, people can make more money by _ things like fruits, nuts and oils, _ _ _ plants that can be used in medicine than by cutting down the forests.E: Oh really? I didnt know that. Now, could you _ some of the reasons why its not a good idea to destroy rainforests?harvestingas well asoutlineA: Sure. You must have heard about the _ animal and plant life in tropical rainforests. Well, there are about _ million species of plants and animals in the world. _ _ half of these live in the tropical rainforests. So, destroying rainforests _ that thousands of these species are _ _ before weve even realized it.rich10More thanmeans dying outE: Ive heard too that the rainforest could _ us _ cures for diseases.A: Yes, there are certainly many new drugs _ _ _ discovered. Another problem is that the _ of forests _ _ global warming. providewithwaiting to bedestruction contributes to Also, rainforests _ a lot of rain so that theres a constant _ of clean water running into rivers and lakes. If the trees are cut down, the rain isnt absorbed and there is flooding.E: So, what can individuals do to help _ _ the destruction?A: Thats a good question . absorb supplyslow downListen to the text. AN EXPERIMENT ON PLANTSPart 1: Listen to a teacher (TH) helping her class set up an experiment.Listen again and fill in the blanks.TH: OK, everybody, this morning were going to do an _ to _ _ three important conditions that seeds need in order to start _.experimentfind outgrowingThe materials are all on the bench.Choose someone _ your group to go and get four dishes and four _ _ cloth, a dish of seeds, some tap water, some boiled water and some cooking oil. Look at the _ on the board. Lets read through them.from pieces ofinstructionsOne: Put the pieces of cloth on the dishes and _ the seeds on the cloth. Label the dishes A to D.Two: Take Dish A and _ the cloth with tap water and _ it in a well-aired warm spot so by the window over there would be fine.Three: Take Dish B, wet it with tap water and put it in the _.spreadwetplacefridgeFour: Take Dish C and put it _ to Dish A. Do not water it.Five: Take Dish D and water it with the boiled water. Then _ a small _ _ oil onto the cloth and put it next to Dish C.Six: Leave them all for a few days. OK, now you can _ _ and _ _ the experiment.nextdropamount ofgo aheadset upPart 2: Listen to the class discussing the results of the experiment. Students include Andrew (A), Rosemary (R) and Sandy (S). TH: Right, lets _ _ whats happened in our experiment. What are the results? Andrew?A: The seeds in Dish A have started growing but _ of the others have.talk aboutnoneTH: Good. _ do you think the seeds in Dish B didnt grow? Rosemary? R: Because it was too cold?TH: Thats right. And _ _ Dish C?Whywhat aboutR: The seeds didnt get _ water so they couldnt grow.TH: Yes. Now, Dish D is interesting. The seeds got _ water and warmth so why didnt they grow? Any ideas? Andrew?anybothA: Well, the seeds got _ water.TH: So, whys that important? Anyone? Well, boiled water has _ oxygen in it and seeds need oxygen to grow. And What about the oil? Sandy?S: Wouldnt the oil _ _ that no oxygen could get to the seeds?boilednomake sureTH: Excellent. _ _. So, whats our _ about three important conditions that a seed needs in order to start growing?S: That seeds need warmth, water and oxygen to grow.TH: Very good. Now I want you all to _ _ the experiment in your science notebook.Well done conclusionwrite up