Senior 2 Biology Compulsory 3 Chapter 4 Section 4 120

All things are foreseen, and those who are not prepared are wasted. Learning biology requires attention to methods and skills, and more importantly, it is necessary to learn to summarize and organize knowledge points. The following is the knowledge points of Chapter 5 of Biology Compulsory 3 that I have compiled for you, I hope it will be helpful to you!

Chapter 5: Ecosystems and Their Stability.

2. The function of the ecosystem: the material cycle and energy flow, which is composed of biological communities and inorganic environments.

4. Characteristics of energy flow: one-way flow, decreasing step by step. Efficiency of energy transfer between two adjacent trophic levels: 10% 20%.

5. Study the meaning of energy flow:

1) It can help people plan and design artificial ecosystems scientifically, so that energy can be used most effectively.

2) It can help people rationally adjust the energy flow relationship in the ecosystem.

6. Similarities and differences between energy flow and material circulation

Differences: In the material cycle (which is global and circular), substances are recycled; As energy flows through trophic levels, it decreases and flows in one direction, rather than in a cyclic manner.

Connection: (1) The two are at the same time, interdependent and inseparable.

2) The fixation, storage, transfer, and release of energy are inseparable from the synthesis and decomposition of matter.

3) Matter acts as a carrier of energy, so that energy flows along the food chain (net); Energy acts as a power force that enables matter to constantly circulate back and forth between the biome and the inorganic environment.

7. Types of information in the ecosystem: physical information, chemical information, behavioral information (peacock opening, bee dancing, courtship).

8. The role of information transfer in the ecosystem:

1) The normal progress of life activities is inseparable from the transmission of information; The reproduction of biological populations is also inseparable.

Transfer of information.

2) Information can also regulate the interspecific relationships of organisms to maintain the stability of ecosystems.

Application of information transfer in agricultural production:

1) Increase the production of agricultural and livestock products.

2) Control of pest animals.

9. Stability of the ecosystem: The ability of the ecosystem to maintain or restore the relative stability of its own structure and function. Ecosystems have the ability to self-regulate, but this self-regulation capacity is limited.

Resistance stability: Ecosystems resist external disturbances and keep their structure intact.

In general, the more components in the ecosystem, the more complex the food web, the stronger its self-regulation ability, the higher the stability of resistance, and the worse the stability of resilience.

11. Ways to improve the stability of ecosystems:

1) The degree of disturbance to the ecosystem should be controlled, and the use of the ecosystem should be moderate, and should not exceed the self-regulating capacity of the ecosystem.

First of all, it is necessary to grasp the basic concept and use it as a technical breakthrough. The so-called problem-solving skills in the biology exam are not something unfathomable, they are the most basic knowledge and concepts, and they are a flash of inspiration when they have mastered to a certain extent. Look for differences – because you do a lot of similar exercises, it is easy to make mistakes in judging similar questions, which is very dangerous.

Second, it is necessary to grasp the basic concepts commonly used and understand their ins and outs. This is very helpful for learning biology well in junior high school. In addition, it is necessary to further understand the derivation process and make some possible changes in the derivation process, which is better than doing a lot of exercises, and can make you better grasp the use of formulas, often with unexpected effects.

Third, it is necessary to grasp the trend of the examination and practice the problem solving norms diligently. Many students think that as long as they solve the closed answer to the question, they can get a full score. In fact, due to the deepening of the new curriculum reform, the examination pays more and more attention to the standardization of the problem-solving process and the integrity of the solution process.

Therefore, it is necessary to standardize the writing process and avoid the situation of "will but not right" and "right but not complete".

Finally, it is necessary to grasp the biological ideas and summarize the methods of problem solving. When reviewing, purposefully decompose the more comprehensive topics into a few simple small topics, so as to draw inferences from one another, simplify the complex, and make breakthroughs step by step; In cooperative learning with classmates, it is necessary to combine the simpler questions into more valuable comprehensive questions. The biggest feature of the junior high school biology exam is that it is shallow, wide, new and lively, therefore, it is necessary to avoid complicated, difficult, biased and strange questions in the review, otherwise, on the one hand, it will waste time, and on the other hand, it will also increase the psychological burden.

The evolutionary aspect is not very important, and the focus of ecology is on population characteristics and population growth curves, ecological balance, and compulsory three key immunizations! 1