Jiangsu Education Press seventh grade biology teaching plan 1 teaching objectives;
1. Describe the types and characteristics of ecosystems.
2. Explain that the biosphere is an ecosystem.
3. Establish the consciousness of protecting the biosphere.
Teaching process:
Import:
Last time we said that our ecosystem has the ability of self-regulation. It seems that if there are more mice on our grassland, there will be more cats, and finally there will be fewer mice to maintain our ecological balance. As we know, there are many ecosystems in our biosphere, and their regulating abilities and characteristics are different.
Introduce the main ecosystems:
In this lesson, we will introduce various ecosystems. First, please open your books P29 and discuss the characteristics of various ecosystems in groups. First of all, what is the difference between forest ecosystem and grassland ecosystem? There are many animals and plants in the forest ecosystem, which are distributed in humid areas and are called "green reservoirs". Grassland ecosystem is distributed in arid areas, with little rainfall and few species of animals and plants. Then why do you call the forest a "green reservoir"? We know that the most reservoir is water, so why can a forest be called a reservoir? Because there are many kinds of animals and plants, we did the experiment of "Plants affect air humidity" last class, so the forest can be called "green reservoir". Let's look at a food chain on the grassland. Because the relationship between predators and arrested people is relatively simple, if one of them is reduced, the food chain will also be destroyed. However, there are many kinds of animals and plants in the forest ecosystem, so if one organism is reduced, it can be replaced by other organisms. A food chain is not so easily destroyed because of the decrease of one organism, so the forest biological system is easier to maintain. Who will talk about the difference between marine ecosystem and freshwater ecosystem? Can creatures in fresh water enter the ocean? So as to review that living things must adapt to their environment. The typical wetland ecosystem is swamp. The more you struggle to fall into the swamp, the deeper you will sink. The swamp has done us too much harm. Should we protect it? More importantly, because marshes can purify water, store floods and fight drought. What are the characteristics of farmland ecosystem and urban ecosystem? They are all artificial ecosystems, which need human monitoring to function normally. Why do you need someone here? (Weeding, fertilizing, watering ...) Without people, these artificial ecosystems, such as forests and grasslands, will be destroyed, which we call natural ecosystems. If people participate in the natural ecosystem, the natural ecosystem will be easily destroyed, but the artificial ecosystem will be easily destroyed without people. This is the difference between artificial ecosystem and natural ecosystem.
Analysis of books and materials:
By analyzing the example of P30 in the book, what other ecosystems are the river ecosystems related to? (fresh water, ocean, forest, grassland, farmland, city ...) It is concluded that any ecosystem does not exist alone, but is interrelated, and the biosphere is the ecosystem inside and a unified whole. By analyzing the DDT examples in P3 1, we can also see that all ecosystems are interrelated, and affecting any one ecosystem will pose a threat to other aspects.
Environmental consensus:
However, we humans are not aware of this. The behavior of our species destroyed the ecosystem. For example, large-scale grazing has caused grassland desertification and caused sandstorms ... which has also hurt ourselves and other creatures. There is also a large number of deforestation, which makes the land more prone to desertification. Cited a lot of pictures and examples. So what should we do for our beautiful planet? What can our classmates do by themselves? (No water pollution, no exhaust emissions, no disposable goods, more trees, less cutting down trees ...) So as to protect our beautiful home.
Postscript of teaching:
This class can talk a little about the introduction of ecosystem, but the students' awareness of protecting the biosphere is still very weak. In this regard, we should arrange more examples and pictures to make students' awareness of environmental protection more profound.
Teaching reflection:
The effect of this lesson is good, because I think it will be boring to introduce each ecosystem simply, so I compare two similar ecosystems and explain their characteristics from their differences. The textbook introduces the swamp, and many students are confused. Why is the swamp harmful to us? I arranged for my classmates to give a short performance, showing the process of falling into the swamp, which not only let them know how to save themselves when they encounter the swamp, but also further deepened their understanding of the wetland ecosystem. Finally, because the content of this class is relatively simple, we arranged some discussions about what harm we and the ecosystem have suffered and how to protect the ecosystem. The students reacted fiercely.
Jiangsu education press seventh grade biology teaching plan 2 teaching goal.
① Explain the structure and function of microscope.
② Microscope can be used independently, and clear images can be observed.
③ Agree with the standard operation method of the microscope and take good care of the microscope.
Important and difficult
Key points: how to use the microscope; Cultivation of students' independent operation ability.
Difficulties: Standardize the use of a microscope to observe the image of an object (ask students to look at the image in the eyepiece with their left eyes and open their right eyes at the same time).
Preparation before class
Teacher: Prepare the microscope and check them one by one (prepare two eyepieces with different multiples); Four kinds of specimens (slides with the word "E" written on them; Animal and plant slide specimens), mirror paper, gauze;
Student: By comparing the color pictures in the textbook, we can know the names of various parts of the microscope and think about their functions. Reflections on the history of microscope development.
teaching process
Go into the new unit ① Read the prologue of the second unit, and make it clear that cells are the basic units of organism structure and function. If you want to explore the mysteries of biology, you must understand cells. Guide students to read 35 pages of pictures in the book, ask questions, read aloud and lead out the theme.
Teachers who introduce new courses determine the introduction strategies and methods according to the specific conditions of schools and students.
After teaching the new lesson, I think it is necessary to use a microscope to understand cells. It is suggested that the cell magnification in the picture should be more than 100 times.
Pick up the mirror and put it away.
Holding it in the right hand and holding it in the left hand; Slightly to the left, install eyepiece. Read the book quickly and bring the mirror and put it away.
Guide the students to read page 37: pick up the mirror and put it away.
It is emphasized that fingers should not touch lenses when placing eyepieces, and students should be educated to take care of microscopes. Guide students to talk about the invention and development of microscope. Q: What microscope are we using now?
1. Structure of microscope
Students work in pairs, read books and know the names of the parts of the microscope.
Answer the teacher's instruction segment name.
Introduction: Today, let's get to know the microscope together and strive to realize that everyone can use the microscope. Guide students to learn about microscopes by reading books.
Randomly dial the student number and take a random test.
2. Use of microscope
Adjust the magnification of the microscope
(1) The low power objective is aimed at the light hole.
(2) Look at the left eye and open the right eye.
(3) Turn the mirror and see a bright field of vision.
Observe:
(1) Place the specimen on the stage, hold it down and face the light hole.
(2) The lens barrel descends until it is close to the sample.
(3) Look at the eyepiece with the left eye, so that the lens barrel rises slowly until the object can be seen clearly. Have an urgent desire to observe.
With a strong curiosity, I read a book while operating a microscope for observation.
Things are different. Some students saw nothing.
Thinking answer: the greater the magnification, the larger the cells and the fewer the numbers; The smaller the magnification, the smaller and more cells are seen.
Induction: put the mirror away and observe it in the light.
Look carefully
Hands-on observation, pay attention to norms. Encourage the use of microscopes. Introduce four kinds of observation specimens:
(1) slides with the word "e" written on them;
(2) transparent paper printed with numbers;
③ Slide specimens of animals and plants;
④ Opaque paper with numbers written on it.
Let the students read first, and then guide them to observe. (It is recommended to observe specimen No.2 first)
Patrol, find common problems, ask a classmate to demonstrate.
Give encouraging comments.
Let the students supplement first, and then let the teacher supplement.
Key points: ① Align the light hole with the low power objective (10x or 8x, short objective).
② The method of rotating the converter should be correct, and students should be educated to take care of the microscope.
3 correction: it should be called bright field of vision, not bright circle.
(4) When the lens barrel descends, the eyes must look at the objective lens. Guide the students to continue to observe.
Let the students understand:
(1) The object is like an inverted image.
② Magnification = eyepiece magnification x objective magnification
③ The optical microscope can only observe objects that can be penetrated by light.
Guide the students to change the eyepiece before observation.
Q: What is the difference in the number and size of cells seen at different magnifications?
Guide students to summarize the steps of using microscope.
Encourage to operate, patrol, check and correct mistakes according to the procedure specification.
Practice thinking and answering. After reading the notes on page 39, start the operation and put the microscope in the box.
Students speak freely. Tip: What should I do after using a microscope?
Conclusion: Give an evaluation and enlighten us: What have you gained from this lesson? Give affirmation and encourage students to make their own specimens and observe them in the laboratory after class. The laboratory is open after class.
Teaching reflection:
Students' first class in the laboratory is to practice using a microscope. When you arrive at the laboratory, you should first emphasize the discipline of the laboratory, so that students can understand that they must abide by the discipline of the laboratory in the future, emphasize the cleaning work of the laboratory, and arrange the students on duty. The "E" slide arranged for students to observe should use low-power eyepiece and objective lens. When emphasizing the relationship between aperture, mirror and light, let students experience it by themselves and write down the problems encountered in the experiment, such as how to make the light brighter and the image clearer, so that students can think while doing the experiment. This makes it easier to understand these relationships, and you can imagine the process of doing experiments when you do the questions, and your memory is more profound.
The teaching goal of the seventh grade biology lesson plan 3 of Jiangsu Education Press;
1. Understand the concept of ecosystem.
2. Understand the composition of ecosystem and the concepts of producer, consumer and decomposer.
3. Understand the concept of ecological balance and the significance of maintaining ecological balance.
Teaching emphases and difficulties:
1. Teaching focus: the concept and composition of ecosystem, the concept of ecological balance and the significance of maintaining ecological balance.
2. Teaching difficulty: the concept of ecological balance.
Teaching process:
First, import.
Recall that I learned two experiments in the first two classes: "the influence of light on mice and girls" and "the influence of plants on air humidity" What is the principle? (Environment affects living things, and living things adapt to the environment and also affect the environment. This shows that our biology and environment are interrelated, inseparable and a unified whole, which we call an ecosystem. This is what we are going to learn today-Chapter 2, Section 4, Ecosystem.
Second, the concepts of ecosystem, food chain and food web.
First find out the concept of ecosystem in books, P22, and draw the concept. What kind of environment is an ecosystem? So is our classroom an ecosystem? Compare the differences between a farmland, a forest and our classroom, so as to understand the concept of ecosystem more accurately. What is an ecosystem made of? There are countless food chains in the ecosystem, which are intertwined and become food webs. We studied food chain and food web in primary school. How do we define these two concepts in the book? P24. Ask students to read the concepts of food chain and food web, and give examples. Grass rabbit wolf. (Emphasize that the arrow should point to the predator). Are these creatures related to other creatures in the forest? (Insects eat grass, mice eat grass, tigers eat rabbits, wolves eat deer ...) Emphasize that the connecting arrows of each food chain point to predators. And briefly introduce primary consumers, secondary consumers …
Third, introduce producers, consumers and decomposers. Briefly introduce each trophic level.
The courseware illustrates several kinds of creatures, and asks students to connect themselves into a food chain to see which group has the most and the most accurate food chain. According to the connection of the food chain, explain the creatures in different positions in the food chain, and introduce producers, consumers and decomposers. Emphasize that the starting point of the food chain must be the producer. Then why are plants called producers and animals called consumers ... so that students can remember them better. What is the sentence composed of leaves, cicadas, yellowbird and mantis? Stimulate students' enthusiasm. Taking these four kinds of organisms as examples, the nutritional structure and links are introduced. Consolidate the knowledge introduced earlier. Take lunch today or yesterday as an example. Name a food chain that ends with students. Discuss the P23 workbook.
Fourth, the number and proportion of various organisms in the ecosystem are relatively stable.
List a food chain, and let the students discuss whether the plants in it will gradually decrease and whether the animals will increase indefinitely, thus leading to the automatic adjustment ability of the ecosystem and making it in a balanced state. Give another example of animation. It is emphasized that the quantity and proportion of various organisms in the ecosystem are relatively stable.
5. If human beings join the ecosystem, the ecosystem will be unbalanced. Look at the pictures and introduce them with examples to cultivate students' awareness of caring for the environment and paying attention to the earth.
1. There are 400 million hectares of natural grasslands in China, accounting for 0.7% of the national territory. The area of natural grassland decreased by about 65? 700,000 hectares, grassland productivity decreased. The grassland ecological environment continues to deteriorate, which leads to the decrease of vegetation coverage, the aggravation of grassland rodent damage and frequent sandstorms.
2. Humans raise a large number of goats. Goats eat grass, mow grass and remove roots, and the damage to grassland is 20 times that of sheep. Due to ecological deterioration, there is no grass to eat, which leads to serious malnutrition of camels, which makes the hump droop and the camels unable to stand.
It is easier to cut down trees than to plant trees. Once the ecological crisis appears, it can't be recovered in a short time.
Sixth, do exercises
Postscript of teaching:
For the previous food chain and food web, because students have learned relevant knowledge in primary school, but have not learned concepts, the focus of this lesson is to let students understand the concepts of ecosystem, food chain and food web. Students are more interested in the connection of the food chain. They can regard the food chain as the connection point of all knowledge points, so that all knowledge points can be connected through the food chain. The importance of maintaining ecological balance, many students can't understand what ecological balance is, and they can deepen their impression through some animations. For example, the courseware can be designed so that when a predator increases, the number of people arrested will decrease, but this situation will not last forever. Let them know that there is a dynamic animation.
Teaching reflection:
The connection of knowledge points is not skilled enough, and the transition between knowledge points is excellent. It is necessary to understand the connection skills between various knowledge points and make the classroom more systematic.