Section 1 Nutrients in Food
First, the teaching objectives
1. Name the main nutrients that the human body needs, and know the functions of the main nutrients and the food sources of the nutrients.
2. Understand the sources and symptoms of inorganic salts and vitamins.
3. Deepen the understanding of the general process of scientific inquiry, and further improve the ability to ask questions, make assumptions, formulate and implement inquiry plans, process data and analyze inquiry results.
4. Pay attention to the nutrients in food and agree that human nutrients mainly come from other organisms in the biosphere.
Second, the focus of teaching
1. Types of nutrients; The general process of query and the processing of query data.
2. The organization of inquiry activities and how to reduce experimental errors are the difficulties in this section.
Third, teaching preparation.
Teacher: Divide the students into groups of 4-5 people, and select the group leader who is responsible for operating, recording, processing data and speaking. Prepare all kinds of materials and instruments for measuring energy in a certain food.
Four, class allocation of 2 hours
Teaching process of verbs (abbreviation of verb)
(1) Nutrients in Food: The First Network of New Curriculum
Listen carefully, think positively and raise your hand to answer.
Write down two kinds of foods you often eat, refer to the textbook P4 1-42 "Table of Common Food Ingredients", and fill in the nutritional ingredients in the food in the textbook.
Discussion: What nutrients are contained in food? Are the types and quantities of nutrients contained in different foods the same? Through comparison and induction, draw a conclusion.
Questioning, asking questions and introducing new lessons.
Patrol and guide students to consult relevant forms.
After most students finish speaking, guide students to compare the nutritional components of these two foods, and guide students to discuss and give encouraging comments in time.
1. 1 Cell life is inseparable from matter and energy.
So, what is the relationship between the nutrients in food and the substances and energy contained in human cells? Functions and sources of sugar, fat and protein Sugar, fat and protein are the main substances that constitute cells, which provide energy for life activities and have a wide range of sources.
Under the guidance of the teacher, read books and communicate with classmates. List foods with high sugar content in Figure IV- 18, and list foods with high sugar content in protein in Figure IV-20.
Discussion: The life of cells is inseparable from matter and energy.
Thinking: What is the relationship between the nutrients in food and the substances and energy contained in somatic cells?
Create situations and guide students to read.
When most students finish, organize discussion, exchange and evaluation.
(2) Inquiry: Measuring the energy in a certain food.
2. 1 Ask questions
Look at the illustrations in the textbook P23 and talk to each other. On this basis, each group asks questions and confirms them.
Under the guidance of the teacher, it is clear that when exploring the energy in food, you can ask questions from different angles; Different questions asked, different assumptions made, and different experimental methods and steps.
Guide students to ask questions.
Teachers' itinerant guidance. Teachers go to various groups for personalized guidance.
2.2 Make assumptions
Each group makes assumptions after full discussion according to the questions raised by its own group.
2.3. Develop an implementation plan
Make a plan according to the inquiry topic determined by the group. After discussing and perfecting the scheme, each group will use our own equipment and materials and appliances provided by the teacher to operate according to the division of labor before class.
2.4 draw a conclusion
By recording and analyzing the experimental data, it is concluded that food contains energy, and different foods contain different amounts of energy. www.xkb 1.com
Provide students with experimental materials and appliances, and guide students to improve their inquiry scheme.
Remind students to pay attention to safety and minimize experimental errors.
Patrol and give appropriate guidance to the inquiry process.
2.5 Expression and communication
Representatives of each group spoke and exchanged views.
Types of water and inorganic vitamins, symptoms of deficiency and corresponding food treatment
Reflect on the wrong person.
Seriously think about the questions raised by the teacher and have a strong desire to explore.
Guide students to find problems from the reports of each group and learn from experience.
Instruct students to analyze the causes of mistakes.
Create questions, introduce teaching and stimulate learning interest.
(3) Edible fiber
According to the role-playing situation, fill in the relevant knowledge in the textbook P25, Table L and P26, Table 2.
Organize and guide students to make diagnosis and discussion.
summary
Speak actively and talk about your gains and feelings.
Practice consolidation
Complete exercises or group discussions by yourself.
Section 2 Reflection on Digestion and Absorption Teaching
First, the teaching objectives
1. Describe the composition of human digestive system.
2. Summarize the digestion process of food and the absorption process of nutrients.
3. Explore the changes of steamed bread in oral cavity by experimental method, and draw a reasonable conclusion.
4. Try to interpret the absorption curve of nutrients in digestive tract.
5. Analyze the relationship between the structure and function of small intestine, and tell the characteristics of mutual adaptation between the structure and absorption function of small intestine.
Second, the focus of teaching
1. Explore the changes of steamed bread in the oral cavity and cultivate students' inquiry ability.
2. Analyze the characteristics of the mutual adaptation between the structure and function of small intestine.
3. Explore the changes of steamed bread in oral cavity, and cultivate students' inquiry ability.
Third, teaching preparation.
1. Teachers make multimedia courseware and wall charts.
2. Preparation of related experiments.
3. Make a folding model of small intestine wall structure.
4. Class hours are allocated to two classes
Fourth, the teaching process
(A) the creation of new curriculum situational guidance
Recall what you learned in the last class and guide students to think and answer the questions raised by the teacher.
Asking questions arouses students' doubts and stimulates their desire to learn.
(2) Changes of food in digestive system
1. Composition of digestive system
1. 1 Look at the picture and answer the questions.
Through thinking, combined with your own experience, answer the structure related to digestion and its main functions in the mouth.
Demonstrate the composition of digestive system and ask questions, so that students can understand the role of teeth, tongue and tongue in eating.
(3) Explore the changes of steamed bread in the mouth.
2. 1 chew the steamed bread carefully and tell me what you have tasted. Think about why it tastes sweet.
Let the students chew steamed bread, and then guide the students to explore.
2.2 Ask questions
Make your own inquiry plan according to the prompts. Exchange query plans and implement query plans.
Tips and Reference Scheme of P30 "Inquiry" in Media Demonstration Textbooks.
2.3 develop and implement the plan
2.4 Group exchange inquiry process, results, conclusions and analysis.
Teachers tour to guide and answer questions.
Put forward suggestions for improvement.
2.5 Expression and communication,
2.6 draw a conclusion
Communicate the observed phenomena in class and analyze the reasons and conclusions.
Encourage and affirm the students' answers and supplement them.
Summarize the concept of digestion.
(4) the whole process of digestion
3. 1 Look carefully and prepare to finish The Adventures of Watermelon Seeds.
Think and answer questions.
3.2 Question: The influence of stomach diseases and hepatitis on digestion and its prevention and treatment.
Observe the experimental phenomenon and answer the questions. Through thinking and answering, we can deepen our understanding that the small intestine is the main organ of the digestive system.
3.3 Demonstrate P33' s "Demonstration Experiment" and ask: What role does bile play in the digestion of fat?
Design tables to summarize the structure and function of digestive system.
3.4 Insert the textbook P35,65438 questions+0,2 and p34 skills training.
Show the forms designed by yourself and evaluate each other.
(5) Absorption of nutrients
Read the data, compare the structural characteristics of large intestine and small intestine, and understand the structural characteristics and functions of small intestine.
Guide students to analyze the "data analysis" in P33, and compare the similarities and differences between large intestine and small intestine.
4. 1 characteristics of small intestine
Internal structure of small intestine in domestic animals
Observe with a magnifying glass to deepen the understanding of the characteristics of small intestine adapting to its function.
Observe the folds and villi on the inner surface of small intestine to understand their functions.
4.2 Model showing the folds on the inner surface of small intestine.
Instruct students to observe the structural characteristics of pig small intestine.
(VI) Summary and after-school exercises
4. 1 Summary: Small intestine is the main place for absorption.
4.2 Exercise the third question in the designated textbook P35.
Teaching reflection
The third part focuses on rational nutrition and food safety.
First, the teaching objectives
1. Give examples to illustrate what is reasonable nutrition.
2. Pay attention to food safety.
3. Try to use the knowledge about reasonable nutrition, design a nutritious and reasonable diet, and care about the diet of the elders.
4. Recognize the unity of environmental protection and food safety.
Second, the focus of teaching
1. Pay attention to the significance of rational nutrition and food safety in a healthy life.
2. Through analysis, we realize the unity of environmental protection and food safety.
Third, teaching difficulties
Design a nutritious and reasonable diet, raise what you have learned into consciousness, and then turn consciousness into behavior.
Fourth, teaching preparation.
Teacher: collect some food packaging bags and boxes before class for teaching needs; Food safety information in TV newspapers and periodicals; Train students before class, instruct the team leader how to conduct investigation and collect information; Design the evaluation column and compare the nutritional differences of lunch recipes designed by students before and after class. Let students know the value of scientific knowledge in guiding healthy life.
Students: four people investigate or collect information about reasonable nutrition and food safety together; Try to design a lunch recipe for your parents or yourself before class; Bring all kinds of food packaging bags; Ask parents how to choose meat, fish and other foods before class.
5. Allocation of Class Hours
teaching process
First, reasonable nutrition.
1. 1 Do not pay attention to the harm of reasonable nutrition
Design lunch recipes for parents before class; Discuss the harm of bad eating habits and unreasonable nutrition independently.
1.2 What is reasonable nutrition?
Observe, discuss and summarize: how to achieve reasonable nutrition?
What about 1.3?
Teachers and students cooperate to make a civilized convention on reasonable nutrition for our class. It is more reasonable to use knowledge to guide life, design lunch recipes and then design a lunch recipe for parents. First in the whole class, then participate in the whole grade design competition, and make good works into a special issue of biology.
Reasonable nutrition
Study independently in groups of four, read the materials provided in the book, observe the illustrations or self-made slides in the book, discuss and communicate with examples around them, and further clarify what reasonable nutrition is and its important significance in healthy life under the guidance of teachers; Design a reasonable lunch menu, cook in person on holidays, and show your love to your elders.
Read the Nutritionist after class to broaden your horizons.
Create problem situations, list typical examples learned in life, guide students to read newspaper information provided in books, and introduce topics;
Guide students to discuss, organize and participate in classroom communication and comments to ensure the correctness and effectiveness of communication. Summarize and show how to achieve reasonable nutrition with slides.
Pay attention to healthy life and carry out emotional education.
(Note: The third section of the book can be used as one of the materials that students can consult when they investigate)
Ask questions before class. Guide students to carry out investigations (visit or consult materials), organize exchanges and make evaluations.
Second, food safety.
2. 1 Overall awareness of the importance of food safety
According to the arrangement before class, release the collected information about food and food safety, listen to the release of students' information, guide students to analyze and organize students to discuss.
2.2 How to buy safe food
A. safe packaged food. (You can read the contents of the package)
B. Unsafe packaged food (exercise a pair of "eyes")
Students read the contents of food packaging boxes, discuss in groups, and recommend the representatives of the groups to speak.
Organize students to discuss and communicate in groups. Affirm the students' speeches and correct or supplement some of them.
Have a group exchange on what you have learned before class.
Listen to students' voices, encourage them to observe and compare more, and suggest that students go to the vegetable market for "practical exercise" after class.
Third, prevent food poisoning.
3. 1 Small experts give lectures on the spot, listen to relevant knowledge and ask questions to supplement.
Listen to the small lecture with the students and fully affirm the students who gave the lecture.
Through discussion, the unity of environmental protection and food safety has been recognized.
Think, discuss and solve problems.
3.2 Discussion: Can we feed poultry and livestock with moldy leftovers or feed? Why?
Some people say that vegetables and fruits with "bug eyes" have less pesticide content, so you can buy them with confidence, right?
Inspired by the teacher, think: What behaviors in real life will eventually lead to food pollution?
Through discussion, we realize the unity of environmental protection and food safety.
Listen carefully to the students' discussion and click in time.
Guide students to deeply understand food safety issues from the perspective of preventing environmental pollution.
Affirm the students' analysis and emphasize the importance of protecting the environment again.
Fourth, understand green food.
Read relevant materials, think and understand the positive significance and important role of green food.
Guide students to understand the information about green food in textbooks, and encourage students to search online for more information.
Learn relevant knowledge through various channels.