"Biological Invaders" is explained in a logical sequence. First introduce the topic, then lay out the phenomenon, then discuss the cause and effect, and finally discuss the countermeasures. Below is the lesson plan I shared, let’s take a look.
Teaching objectives
1. Understand the knowledge related to biological invaders.
2. Clarify the order of explanation, summarize the key points, understand the expression effect of the explanation method in the text, and figure out the language.
3. Cultivate students’ environmental awareness and awareness of danger, enhance their awareness of prevention, and work hard to build their homes and protect the environment.
Teaching focus
First, explain the sequence and methods
Second, enhance environmental awareness.
Teaching Difficulties
Arrangement of the damage caused by "biological invaders" to the ecosystem and the losses caused to human beings
Teaching preparation
< p> Students collect relevant informationTeaching steps
1. Situation introduction
1. Students read the poem "Bu Di Hou Fu Chrysanthemum" together and guess the name of the flower.
When autumn comes on September 8th,
I will kill all the flowers after they bloom.
The towering incense array penetrates Chang'an,
The whole city is covered with golden armor.
(Teacher: "After I bloom, hundreds of flowers will kill you", which vividly demonstrates the nobility of chrysanthemums that bloom proudly and independently in the cold autumn. "The soaring fragrance array" has long been dispersed in the sky of history, and has been used for more than a thousand years. Today, years later, the situation of "after the yellow flowers bloom, hundreds of flowers will be killed" has reappeared in modern cities. Please listen to today's news)
2. News report: "After the yellow flowers bloom, hundreds of flowers will be killed" --- - Canadian goldenrod appears in Changsha
2. Overall perception:
Read the text carefully to obtain relevant information:
1. Through the reading just now, you have gained What do you know about biological invaders?
2. In what way does the author tell us this knowledge?
Opening: Assume a situation, introduce the topic, and explain
Paragraphs 2-4: Write specifically about what biological invaders are and their harm.
Paragraph 5: Analyze the causes and ways of increasing biological invaders.
Paragraphs 6-7; Biologists and ecologists have different attitudes towards biological invaders.
Paragraph 8: Countries around the world are currently taking corresponding measures.
Ask a question------analyze the problem------solve the problem: logical sequence
3. Partial speculation:
This article uses illustrative methods such as listing numbers, giving examples, and making metaphors. Please use concise language to analyze its expression effect.
1. List the numbers:
① "Nine of the eleven species of birds have been driven to extinction" ------- The changes in the numbers illustrate the impact of biological invaders on the natural ecosystem. The harm is great.
② Costing billions of dollars------illustrating the huge economic losses caused by biological invaders to humans.
(Additional emphasis: The use of numbers makes the language very accurate and conforms to the scientific characteristics of expository writing. In addition, the appropriate selection of adverbs also enhances the accuracy of the article. Such as "only" and "jiu". )
2. Give examples:
① Take dandelion as an example ------ illustrate that the migration of organisms without human intervention will not affect the original habitat. Too much damage to the ecosystem.
② Clams, longhorned beetles, red ants, etc. ------ show that biological invaders have brought great harm to human beings.
③Vegetables, fruits, pets, etc.------Indicates that biological invasion is caused by human factors.
3. Analogy:
①The topic "Biological Invaders" is a metaphor, explaining:
a Biological invasion is an "immigration" behavior;
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bBiological intrusion will cause harm to humans and nature.
② The scallop is compared to a "smuggler", indicating that it has landed on the North American continent without people knowing it and quietly caused harm to humans.
(Emphasis: Biological invasion is relatively unfamiliar to most people. The author uses metaphors to make the language more vivid, enhance the interest of the article, explain the profound things in simple terms, and achieve the purpose of popularizing science knowledge. . In addition, the use of words also has similar effects (such as "Xiao Gathering in the Mountain Forest", etc.)
IV. Collaborative Research
1. Based on the existing information, introduce one species of biological invaders (name, source, characteristics, hazards, etc.) and formulate corresponding prevention and control measures based on their characteristics.
2. The whole class exchanges and cooperates in learning results. Teachers inspire thinking: prevention, management, utilization.
5. Summary and improvement:
Goldenrod may make our provincial capital "full of golden armor", Mikania will swallow up Lingding Island, water hyacinth will die in Dianchi Lake in Yunnan, airplanes Grass is about to take over Xishuangbanna, and ricegrass is destroying the seaside tidal flats... According to statistics, my country has 107 species of exotic weeds, 32 species of exotic pests, and 23 species of pathogenic bacteria, causing economic losses of 57.4 billion in agriculture and forestry every year.
When environmental protection was mentioned in the past, what often flashed in people’s minds were scenes of deserts, turbid water flowing across them, and deforestation. Through today's study, we clearly realize that "biological invasion" has become another serious issue before us. The alarm bell to protect the environment is ringing in our ears again. I hope that students will continue to pay attention to this phenomenon and contribute our wisdom and strength to resist and prevent biological invasion!
6. Homework:
Choose four words from the appendix after class that you think are well used, and try to figure out their taste and function.