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Nature Exploration "The Pressure of Homework Examination in Basic Courses of Natural Science (1)" Chapter 1: 1. Paper making, printing, compass powder. The observed Darwinian law of conservation of energy and the transformation of cell theory have expanded the scope, improved the observation accuracy and speed, and transformed the sensory form. There is a certain scientific basis for speculation. In the 20th century, we chose 1B 2D 3C 4D short answer 1. Characteristics of the technological development of Shi Shu: (1) Science and technology have experienced a comprehensive and unprecedented revolution. For example, in the field of physics, modern physical system theory establishes the pillars of relativity and quantum theory; Biology reveals the structure of DNA, and the new technological revolution of genetic engineering will play a great role; (2) Science is comprehensive. People's horizons have expanded by more than 65,438+ten thousand times in micro and macro, and they have a deeper understanding of nature, biology, chemistry and physics, and have more and more mature and significant scientific and technological achievements, which is a comprehensive achievement research; (3) Science and technology have become the primary productive force, and human life has undergone tremendous changes. In the 20th century, technology played an increasingly prominent role in society, which played a decisive role in the development of human history and the prosperity of the country. People's quality is improved, life expectancy is prolonged, and the harmony between man and nature is pursued. 2。 The knowledge points of the difference and connection between observation and experiment are: the concept of observation and experiment and their connection. Analysis: The key point of this question is that these two concepts need to be explained first, and then compared to determine the differences and connections between them. Obviously, there are four steps to answer: observation usually refers to the observation of nature, which is a basic method of empirical knowledge. Experiment is a research method in which people artificially arrange to control or simulate natural phenomena as much as possible according to a certain purpose and observe them under the most favorable conditions (as defined above). The connection between the two: the basic method of scientific understanding. The difference between the two can only be observed under natural conditions and has limitations. The most important phenomenon that is not conducive to identity is internal regularity, which plays a decisive role. Experiment is an exploratory activity. It was first discovered in natural science research that the new theory was put forward on the basis of experiments. It enables us to intervene, artificially change and control the most important aspects of rules through natural objects as much as possible, reproduce the interference of internal, external and accidental factors, give full play to subjective initiative, and expose the nature of natural phenomena. Repeated experiments and imagination are an important feature, which can be tested by the public and make people trust the experimental results. Answer note: be concise and leave this out. What is the knowledge assessment point of this problem? Direct experiment and simulation experiment introduce the concept of direct experimental simulation. Direct experiment refers to the phenomenon that experimenters directly interact with experimental devices or experimental research objects. The experimental device for simulating the experimenter is the experimental object model or similar prototype simulation object in the study of indirect action phenomenon, not the prototype. Note: The difference lies in the "direct action" or "indirect influence" of the former and the latter. Brief introduction of STS science education STS is the abbreviation of English words of science, technology and society. STS science education emphasizes the guiding ideology of science, technology and society, the application of science and technology in social production, life and development, and the relationship between organization and implementation of science education. See Chapter 2, Article 27: Filling in the blanks of natural substances. Atmosphere, hydrosphere and biosphere II. A continental slope of the ocean, a continental shelf basin. Effects of metabolism. See page P 120 for the formula of amino acids. Nucleotide DNA ribonucleic acid 6. Select 1C2C34C, three short answer questions 1 in the middle, late and late mitosis. Composition and characteristics of persimmon solar energy system. Knowledge evaluation topic: composition and characteristics of solar energy system. Analysis: The key to this question is to answer the structural materials of 36 galaxies. The solar system is a celestial system centered on the sun. The composition of the solar system (the first definition of the solar system): the sun and planets, satellites, comets, meteors, interplanetary substances, mainly the sun and nine planets (the order from near to far from the sun: Mercury, Venus, most of their mass, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto); Focus on the sun, light and heat from the sun. The composition and characteristics of solar energy system are expounded respectively. The solar system is centered on the sun, and planets, satellites, comets, meteors and interplanetary matter revolve around the sun. Main fields of solar power generation system. Answer note: At a glance, the positions of the nine visible planets are all drawn on the chart. For example, Mercury is closest to the sun, the third place on the earth is far from the sun, and Venus and Mars are close neighbors of the earth. News worth mentioning: In 2006, the International Astronomical Congress adopted a new definition of planets, and determined that there are only eight planets in the solar system. Pluto, which has been the last seat of the nine planets in the solar system for more than 70 years, was expelled from the planetary family after years of arguments and days of quarrels at this session of the International Astronomical Union. What are the material composition and physical characteristics of various fields in the earth? The topic of knowledge assessment point is the composition and characteristics of various fields in the earth. Analysis: The inner circle of the earth is difficult for students to understand to some extent, mainly because the meaning of the three concentric circles of the shell, mantle and core, including the 47 inner circles of the earth, is not profound. To know the significance of the crustal part of the inner three spheres, especially the individual characteristics, we must first have a certain understanding of the memory work on the map. The outermost crust located at the center of the earth is called the core of the mantle. It is very important because in human life, such as earthquakes, they occur in the earth's crust, and mineral resources are mainly found in the earth's crust. The most detailed part of the earth's crust related to people, the interior of the earth. In order to understand the difference in spatial distribution of differentiated crust itself and the difference between another Si-Al layer and a Si-Mg layer in the internal structure of continental crust and marine crust, it is necessary to understand the difference in thickness, composition and composition. So, what are the characteristics of the "physical composition and physical properties of the ball" in the analysis question? It should be pointed out that the upper crust is in the infield of the earth, with an average thickness of 35 kilometers, and the continental thickness (double-layer structure, silicon oxide, aluminum oxide layer and lower silicon magnesium layer; The thin ocean area (single layer of Si-Mg layer) accounts for a very small part of the global total mass. The low-density mantle, the upper mantle and the lower mantle are desilicated, and the oxygen, iron and magnesium components are increased. The increased global iron and nickel mantle density accounts for about 7%, and the core components of iron, silicon and nickel at home and abroad are gradually increasing inward, accounting for 3% of the global total mass, and the density is extremely high. Matters needing attention in answering questions: the answering steps, from outside to inside, are graded step by step. 3。 To evaluate the meaning of knowledge, the basic characteristics of the earth's surface are among 49 questions about the meaning and basic characteristics of the earth's surface. Pay attention to the characteristics listed in the answer. You should first answer what people on the surface of the earth mean. Don't limit the order of questions. The characteristics of the earth's surface are a place where gas, liquid and solid coexist, where external forces are superimposed, where inorganic substances and organic substances are transformed into each other, and where human beings live together. Its significance lies in that it is directly related to the natural geographical environment of human beings on the surface of the earth, and it is closely related to the fate of human beings. Only when the material conditions on the earth's surface, such as air, water, sunshine and food, become necessary for human life can human resources be developed. What are the characteristics of land and sea distribution on the earth? See P5 1 on page 5 of this book. Methods 1: firstly, three kinds of crystals were dissolved in water, and silver nitrate solution and dilute nitric acid were added, which had the following characteristics: fine salt that did not react with sugar, dilute nitric acid generated white precipitate, and the white precipitate disappeared after adding acid. Method 2: Take a small amount of three kinds of crystals in a test tube, introduce gas, sugar after the reaction, and add water to the other two test tubes that have not reacted again, and then add soda ash and other fine salts. 6 See page P 108 for the definition, for example, page P 108 for homework evaluation of basic natural science courses (II) Chapter II: Selection of liquid reaction precipitation of natural substances 1. The gaps filled have been reduced. Blue weak acid alkalinity, H argon sodium chloride 2 0 -2 reduction solution 1. The chemical properties of elemental sulfur and halogen elements (sulfur atoms with strong oxidation resistance of chlorine atoms on the surface) were compared. Analysis: to answer this question, we must first understand the meaning of the question. The best reaction equation for comparison is to improve the chemical properties of sulfur atoms and chlorine atoms. Obviously, the answer to the fourth step is: the first listed chalcogen and halogen-containing elements: (1) contain oxygen, sulfur, selenium, tellurium and so on. A chalcogen element, which represents oxygen, is characterized in that a single mass represents chlorine, and metallic iron of (3) reacts with chlorine (1) and sulfur to obtain formula (2) and (4). The analysis shows that (1)(2) is stronger than sulfur atom, and the oxidation resistance of chlorine atom is: metallic iron reacting with chlorine, and the reaction of metallic iron of iron ranges from 0-. 3, the reaction conditions are iron metal iron and sulfur, and the range of iron is 0->; 2 valence, the reaction from reaction is more difficult than the reaction with chlorine and sulfur. It should be pointed out here that under different reaction conditions, the valence state of iron in the reaction product is also different. From the atomic structure, the number of electron layers outside a chlorine atom and a sulfur nucleus is the same, but there are more chlorine atoms with nuclear charges than sulfur atoms, and the electron affinity makes it easy to obtain electrons. Chlorine atoms and sulfur atoms are highly oxidizing. Warning: Others, such as the chemical properties of chalcogen and halogen elements analyzed by the reaction of hydrogen and sulfur vapor, can also be 2. The atomic number is the atomic structure diagram drawn by several families in the first few cycles of 17 element in the periodic table, which describes whether they belong to metallic elements or nonmetallic elements. The topic of knowledge evaluation is the answer to the periodic table of elements. Ask students to look at the periodic table of elements to find the answer to the question, and draw the adjustment diagram of atomic structure. Textbook 89 no longer expresses opinions, but only gives students reference answers. The element 17 is chlorine, and the third period of the periodic table of elements, the first main group 7, belongs to nonmetal, which can be divided into the following chemical equations for the reaction of 3( 1) with methyl chloride to generate chlorine, and which organic chemical reaction it belongs to. Title: Organic reaction equation. Analysis: a? The knowledge point of alkyl chlorination reaction is continuous reaction. ? CH _ 4+Cl _ 2 methyl chloride+hydrochloric acid However, there will be a smooth substitution reaction between methane and chlorine. Warning: It will not react with methyl chloride. After this termination, the reaction of methanesulfonyl chloride and chlorine will continue, and the methane molecules of hydrogen atoms in the mixture of CH 2 Cl 2, chloroform and carbon tetrachloride will be gradually replaced by chlorine atoms, resulting in four substituted products. This problem needs to be understood. The exact meaning of substitution reaction is chemical reaction equation (2). 120- 130 hydrogen chloride and mercuric chloride catalyze the reaction to generate acetylene. Title of knowledge evaluation point: analysis of organic reaction equation: the catalytic addition reaction of acetylene molecular formula C2H2, 120- 130 and HgCl2 with hydrogen chloride, thermochemical reaction equation (3) of ethyl chloride with sodium hydroxide solution in ethanol, and the specified type of organic chemical reaction. Topic: Knowledge evaluation point of organic reaction equation. Similar analysis: As mentioned above, the correct molecular formula of chloroethane and ethanol in sodium hydroxide solution is written as CH3CH2Cl, and the thermal elimination reaction occurs. Precautions for Reaction Equation: First, it is a reaction equation that needs attention. The formula is written by elements, followed by conservation conditions and elements that protect the environment. Afforestation and reforestation (from two aspects) Title: Environmental protection measures. Analysis: The significance of environmental protection measures for this problem has certain limitations, and the key point of afforestation and reforestation needs to be how it works. Obviously, the students didn't study the topic carefully and didn't say hello well, so the answer was not fully in place. It must be described in two aspects, namely "green" and "afforestation" introduces the role of environmental protection, doesn't it), and the answer is given in three steps: (1) Increase afforestation and renew afforestation. (2) On the one hand, the photosynthesis of green plants absorbs carbon dioxide and releases oxygen, so that in the process of burning and breathing carbon dioxide, the consumed supplementary breath consumes oxygen, which is conducive to maintaining the atmospheric composition unchanged; (3) On the other hand, forests can purify air, adjust climate, reduce noise, disinfect water sources and improve soil quality. In addition to the above points, we should pay special attention to many terms and concepts involved in short answer questions. Chapter: Nature, the gap filled by sports. The quality has improved. Greater than 3. Strict orbital period and speed. At 2: 00, when 1D 2C three-dimensional short answer 1 is selected in figure 4B 3, the total external force and the acceleration and velocity changes when the external force is the same or the external force moves decrease according to the decrease of the total external force, and the acceleration must be reduced, but the velocity still increases. When the total external force decreases, the total external force is opposite to the direction of motion, and the acceleration reduction speed also decreases. 2 What is power bias? What are its characteristics? Book P 196 3. Division and five earths? What are the characteristics of each region? Book P20 1 divides the latitudes of the five zones of the earth, its south, the Cancer of the Tropic of Cancer in the Arctic Circle, and its south boundary. Between the tropical areas in the south, the tropic of cancer, the height of the sun, strong light and the length of day and night have little change. South and North Temperatures The Tropic of Cancer and South Temperate Temperatures are respectively in the south of the Arctic Circle. There is no direct relationship between sunshine and region all year round, and the length of day and night changes. In the area between the north and the south, south of the Arctic Circle, the height of the sun is very small, the light intensity is low, and the day and night are extreme, respectively in Xia Dong. Answer (1) w = mgh = 20× g×10 = 200g (j) (2) A bird with a flying speed of 300 m/s, a length of 20 cm and a mass of 0.5 kg collided. After the collision, the speed of the original bird is relative to the speed of the dead bird and the aircraft with the same speed. Estimate the impact of birds on aircraft (provide collision time divided by aircraft speed estimate for birds). The knowledge check point of this problem is momentum theorem. This is a very similar title. The conditions given in the title should be used in this topic: the length of collision time divided by the bird collision time t seconds estimated by the aircraft speed, and the speed of key analysis to be grasped is very small. The pre-collision velocity V 1 of the bird is 0 (this is a problem based on the above meaning: the significance of the original bird on the ground can be ignored). After the collision, the speed V2 is the speed of the plane (this is according to the meaning of the question, because the speed of the dead bird plane is the same), and the bird speed changes △ V = V2-V 1 = 300m/s, and then the influence of F =△P/ ton of birds on the plane is calculated. Based on the above analysis and ownership solution, students can find the answer here without commenting, but the answer is for students' reference. The pressure of examination of natural science basic courses (3) Chapter IV: Life and nature are fill-in-the-blank questions. Autotrophic and heterotrophic. Photosynthesis, inorganic substances, solar energy, organic carbohydrates, lipids, protein, minerals, vitamins and water. Asexual reproduction, sexual reproduction of salivary glands, variation of liver and pancreas, heredity, selection, variation and genetic reproduction excess, struggle for existence, survival, survival of the fittest 7. Vitamins and inorganic salts are two choices, and1a2d3d45c is three experiments. Separation. High granule, yellow leaf organ 3. TtTt, and Tt, TT, TT chapters: fill in the blanks on resources, energy and their use. Correlation 2. Light oil, heavy oil and heavy oil. Magnetic effect. Take prompt action, automatically 4. Newton's third law, law of conservation of mechanical energy, law of conservation and transformation of energy 5. Sulfur, vulcanization, the shape of grid 6. Strengthen research on solar energy, hydropower, wind energy and other renewable energy sources? Development and utilization of bioenergy, choice of nuclear energy and fossil fuel1d2a34c. Answer 1. Describe the characteristics of different types of natural resources. The knowledge assessment point of this problem is the characteristics of natural resources. According to the meaning of the question, this question is to clarify the concept of natural resources first, then explain the classification of natural resources, and finally explain the characteristics of various resources. Obviously, the answer comes to the fourth step: from the natural resources in the natural environment, what ways can various people use? Broadly speaking, all elements except people can be regarded as the natural environment of natural resources. But it is usually limited to the potential utilization of natural resources and natural conditions. The concept of resource resources can be divided into four categories: natural elements, land resources, water resources, biological resources and mineral resources, and can also be divided into three categories: non-renewable resources, renewable resources and renewable resources. Please pay attention to the natural elements and reproducibility of the two classification relationships. What kind of renewable energy are you looking for? For example, biological resources are renewable resources, mineral resources are non-renewable resources, and minerals such as iron and copper will not be updated. The four types of resources are concentrated in land resources and water resources, because this is a major resource problem facing our country. Land resources should first understand the dual attributes of this concept, which are influenced by both natural factors and more and more social and economic factors. It is a unique resource with dual attributes, which is the most prominent point compared with other types of resources. Land resources have four characteristics, that is, the amount of land with limited land production capacity has fixed land in time, space and region, and has certain production capacity and limited basic characteristics. Characteristics of land resources in China: different land types, relatively less land use, and extremely unbalanced distribution of various land resources. Water resources have three basic characteristics: the proportion of fresh water resources is small, water resources are renewable natural resources, and water resources have the closest relationship with human beings. Pay attention to the contents behind the superficial phenomenon: First, the water institutions, water resources and fresh water resources on the earth's surface are mostly very limited, so we can use the percentage data in the listed materials to deepen our understanding; Diwater is renewable and reusable, but in fact, the process of regeneration conditions is not evenly distributed, so it is not infinite. We must protect water resources. The characteristics of water resources in China are rich in total amount and less per capita; The spatial distribution of water resources is uneven; Water resources are unbalanced in time and distribution. For the characteristics of biological resources and mineral resources, see the textbook 309-3 14 (omitted) to write the chemical equation of the reaction. (1) Ammonia oxidation to produce nitric oxide (2) Main reaction principle of ironmaking (4) (3) Evaluation of electrolytic water chemical reaction of salt during bipolar combustion of methane. (1) 4NH3+5o2 = 4NO+6H2O (2) CH4+2o2 = CO2+2h2o (ignition) (3) Fe2O3+3co = 2fe+3o (4) Anode: 2Cl combination -2E = CL2 cathode: 2h++2e = 3. The attached figure is evaluated. This question summarizes 328 textbooks for reference, and the following is the answer. Advantages: (1) is a renewable heat source. The thermonuclear reaction time in the central area of solar energy is estimated to last for 6 billion years. (2) High energy. The energy form of the sun reaching the land surface of the earth through radiation is about 6.5438+0.7 million kilowatts, which is equivalent to the total energy consumption of more than 3.5 million times in the world. (3) No pollution. Solar radiation will not produce pollutants. Disadvantages: (1) Day and night, and the weather. Direct use of solar energy for heating or power generation cannot be used continuously, so it is still technically difficult to try solar energy storage. (2) The cost of using solar energy is high. Investment in machinery and equipment increased. 4。 Causes and protection of metal corrosion. The knowledge test point of this problem is metal characteristics. This question is a relatively simple and complete textbook for students' reference. Causes of metal corrosion: direct chemical reaction caused by etching (chemical etching); Corrosion is caused by galvanic cell reaction (electrochemical corrosion). Protection methods: a. Change the metal structure; B, covering a protective layer; C. electrochemical protection. A: A 40-meter-high waterfall flows through 1.0× 104 kg of water every second. If it reaches 25% of the current power generation, will it be very powerful? Calculating energy and its transformation. Analysis: firstly, according to the power supply equation in water and the known condition that 25% of water energy can be converted into current, the generated power generation is determined. Solution: Flow power: According to the electric power calculation formula P = W/T = MGH/ ton = 1.0? 104? 9.8? 40/ 1 W = 3.9？ Power is106 W. power: p electricity = P? 25%= 9.8? Attention should be paid to the answer calculation of 105 W, and the second is to pay attention to the consistency of unit conversion. There must be more problem analysis and really understand the formula, which is not easy to do. The transmission line resistance of 2 is 1.0 ohm, and the total output power is 100KW. What is the power loss of transmission line heating in 400V low-voltage transmission? Switch to 10000V high voltage transmission? The knowledge assessment point of this problem is the application of electricity. Analysis: In a circuit, the voltage across the circuit is directly proportional to the intensity of the current. According to the analysis of the meaning of the problem, it shows that the overtime voltage change also changes the current flowing through it, which is the actual power change. Find the answer to this question in the case of public trial of electric power. Solution: Let P 1 400V transmission line consume low-voltage power. Set 100KW, and the electric power calculation formula for 400V low-voltage current transmission is P = VI I 1, I 1? = P / V =？ 100KW/400V = 250A Therefore, p1= I12r = 250× 250×1= 62500w is set to I2 transmission 10000V. At present, I2 = p/v2 = 65000v v. 10A Then, when switching 10000V high-voltage power transmission, the power consumed by the power of the transmission line is p2p2 =/i22r =10x10x1=100W3. Rated voltage of electric water heater is 220V, resistance160Ohm, and electric power w? Joule heat per minute? The knowledge assessment point of this problem is the comprehensive application of electricity and Joule's law. Analysis: this problem is similar to the last one, electric water heater, electricity, heat, and then calculate the meaning of the electric power calculation formula based on Joule's law. Solution: The power formula P = VI = V2/R,1600 = 302.5W In Joule's Law, P = 220× 220, and the heat generated by the electric water heater per minute Q =, PT = 302.5W 60 seconds =18150J. Remember the formula first. The pressure of examination of natural science basic courses (4) Chapter VI: Fill in the blanks with science and technology in life. The sum of optical dense medium and optical sparse medium is greater than 2. Temperature, solid, liquid, air (or gas) 3. 20KHz，20Hz 4。 Radio waves, gamma rays 5. Text, telegram, telephone, image data. Automatic, output two options 1D 2B 3C 4C. Answer magnifying glass, camera and slide with convex lens imaging, test imaging. The knowledge check point of this problem is the principle of convex lens imaging. This title key means three different images according to the meaning of the question. Obviously, the answer that one step is divided into four steps is that a magnifying glass is used to observe the detailed information of an object. Simple vision is that the converging lens of the optical device has a smaller focal length than the eye. Use a magnifying glass to make it close to the eyes and put it in the focus to form an upright virtual image. Its function is to reduce small objects into enlarged images. The imaging principle of magnifying glass camera can also use convex lens to form a reduced real image, which belongs to U.