What are the science questions for primary school students?

I. Solar system

1, the sun is a huge sphere, which can glow and bring us light and warmth.

2. The surface temperature of the sun is about 60,000 C, and the internal temperature is as high as150,000 C to 20 million C; The volume of the sun is 6.5438+0.3 million times that of the earth, and the distance from the earth to the sun is about 65.438+0.5 billion kilometers.

The sun takes the whole solar system around the center of the galaxy. The sun was born about 5 billion years ago, and its life span is about 65.438+00 billion years.

4. The height of the sun: refers to the angle between the line of sight of people looking at the sun and the horizontal line of sight of people.

The eight planets of the sun are Venus, Mercury, Jupiter, Mars, Saturn, Earth, Uranus and Neptune. Jupiter has the most satellites. What fascinates people on earth most is Mars, whose environment is closest to that of the earth.

6. The revolution direction of the earth is consistent with the rotation direction, both from west to east. A revolution takes a year. The revolution of the earth has led to the change of the length of day and night and the change of the four seasons on the earth.

7. The earth is constantly spinning, and the time of one rotation is one day, about 24 hours. When rotating, the side facing the sun will be illuminated by the sun, which is daytime, called day; The side facing away from the sun is outside the night, which is called night. When the earth keeps spinning, the phenomenon of alternating day and night will appear.

8. From outside to inside, the earth is: crust, mantle and core. The crust is a thin shell on the earth's surface, with an average thickness of about 17 km. The average thickness of the mantle is about 2900 kilometers, and most earthquakes are caused by mantle activity. The radius of the core is about 3470 kilometers, and the temperature is about 3000 degrees Celsius to 5000 degrees Celsius.

9. About 7 1% of the earth's surface is covered by seawater, and the rest is land. The earth is the only known living planet.

10, the surface of the moon is uneven, with craters, highlands and the moon sea. There is no air on the moon, so there is no sound. The distance between the earth and the moon is about 380 thousand kilometers; The moon itself does not shine, and moonlight is the sunlight reflected by the moon; The maximum temperature of the moon during the day can reach 1200C, and the minimum temperature at night can be reduced to below 1800C; The moon is much smaller than the earth, only 49 moons are as big as the earth, and the gravity of the moon is only 1/6 of the earth.

1 1. The moon is a satellite of the earth. It keeps spinning around the earth. The direction of revolution is from west to east, and period of revolution is a month in the lunar calendar.

12, the phase difference of the moon is called the moon phase. The moon phase is formed because the moon revolves around the earth, and the cycle of the moon phase is one month in the lunar calendar.

13, the sundial is an ancient timekeeping instrument, equivalent to a watch now; The standard watch is an instrument for measuring seasons and years in ancient times, which is equivalent to the current calendar.

14 and 1 light year are the distances that light travels in vacuum 1 year. 1 light-year is about 9.5 trillion kilometers.

Second, the earth knowledge

1, April 22nd is Earth Day.

2. The "face" of the earth refers to the appearance of the earth, referred to as "landform". There are Ya Dan landform, coastal landform and glacier landform.

Wei Gena guessed that the two continents might be connected in ancient times. The application of "continental drift theory" has played a great role in mineral exploration and natural disaster prediction.

There is only "one day and one night" near the South Pole all year round. "daytime" is the whole summer, warm and bright; "Night" is the whole winter, cold and dark.

5. Antarctica is a continent: Antarctica; The Arctic is an ocean: the Arctic Ocean.

6. Li Siguang is the founder of the geological cause in China.

There are sand, clay, water, air, small animals and plants in the soil.

8. According to the amount of silt and clay particles in the soil, people divide the soil into three categories: the soil with more clay particles is called cohesive soil; Sandy soil is called sandy soil; Soil with similar content of sand and clay is called loam.

9. Earthworms, also known as natural plows, like soft and moist soil. It can improve the soil. In the Olympic Village of Sydney Olympic Games in 2000, 6.5438+600,000 earthworms were used to treat domestic garbage.

10, the changes of substances in the process of use and waste reuse, some are morphological changes, some are new substances.

1 1. Garbage disposal methods mainly include: open-air stacking, sanitary landfill, incineration, composting, classified recovery and reuse. Among them, source reduction, classified recycling and comprehensive treatment are the best garbage disposal methods.

12, the common soilless culture methods are hydroponics, sawdust culture and sand culture.

13. Mineral resources are the product of the long-term development and evolution of the earth's crust, which are generally divided into energy minerals, metal minerals and non-metal minerals.

14. After ancient plants were buried underground, after a long-term change, they would form an energy mineral-coal. In China's energy structure, the proportion of coal is too large, reaching about 70%.

15. Energy minerals include coal, oil and natural gas.

16, and the hardness of rock is divided into 10 grades. Diamond is the hardest with a hardness of 10, and mica is the softest with a hardness of 1.

17, temperature, water atmosphere and other factors will cause weathering.

18, the Pacific Rim region has the most frequent seismic activity.

19. Zhang Heng, a scientist in the Eastern Han Dynasty, invented an instrument for measuring earthquakes-the waiting wind seismograph.

20. Green community refers to a civilized community whose facilities meet the requirements of environmental protection and whose environmental management system and public participation mechanism are relatively perfect.

2 1. Green community construction includes: green building, community greening, garbage disposal, sewage treatment, water-saving facilities, energy-saving facilities, new energy facilities, perfect management system and good living habits of residents.

22. Nanjing, Wuhan and Chongqing are the so-called "three furnaces" in China. In China, the hottest place is Turpan in Xinjiang. The coldest is the northernmost Mohe River.

Third, electricity and magnetism.

1. Magnets have two poles: South Pole (S Pole) and North Pole (N Pole).

2. Magnets can refer to north and south; Magnets can adsorb iron products; The magnet has strong magnetic force at two poles and weak magnetic force in the middle; Magnets repel each other and attract each other.

When the coil is electrified, it becomes as magnetic as a magnet. Adding an iron core in the middle of the coil will make the coil more magnetic.

The coil with iron core inserted in the middle is called electromagnet. The electromagnet produces magnetism when it is energized, but disappears when it is de-energized, and the magnetic size and pole can be controlled.

Compass is one of the four great inventions in ancient China. Sina is the ancestor of compass.

6. The earth is a huge magnet.

7. China is the third country to master the technology of maglev train.

8. When small beads, wires and batteries are connected in a circle, a loop is formed, and current can flow in the loop.

9. We should pay attention to saving electricity and using electricity safely.

10, copper, aluminum, iron and other easily conductive objects are called conductors. Rubber, plastics, ceramics and other items. Insulators that are extremely difficult to conduct electricity are called insulators. The boundary between conductor and insulator is not absolute.

1 1. Small light bulbs and buzzers in electric toys can convert electric energy into light and sound.

12, the current is directional. Using diodes, the circuit can only pass current in one direction.

13. Common power generation methods: hydropower, thermal power, nuclear power, wind power, solar power generation, etc.

Fourth, sound, light and heat.

1. Use the alcohol lamp correctly and safely: ① When lighting the alcohol lamp, don't tilt the lamp body and light it from the side with a match; The flame of alcohol lamp is divided into three layers, and the outer flame temperature is the highest, so the object should be heated on the outer flame; (3) When it goes out, you can't blow it with your mouth, but cover it with a lamp cap. After the cover is damaged, lift the lamp holder and cover it again to prevent it from being opened next time.

2. The flame of alcohol lamp is divided into three layers: outer flame, inner flame and flame core. The external flame burns most fully and has the highest temperature.

3. Combustion conditions: combustible substances, oxygen and a certain temperature.

4, paper cups can boil water.

5. Objects generally have the property of thermal expansion and cold contraction (thermal expansion and cold contraction). However, the volume of water is the smallest at 4℃, and it will expand above or below 4℃.

6. Heat is always transferred from high-temperature objects to low-temperature objects.

7, 1 kcal = 4.2 kJ.

8. There are three ways of heat transfer: conduction, radiation and convection.

9. Sound is produced by the vibration of objects. The vibration of gas, liquid and solid will produce sound. Sound can travel in solids, liquids and gases.

10. Common orchestral instruments can be roughly divided into three categories: stringed instruments, wind instruments and percussion instruments.

Music has three elements: loudness, pitch and timbre.

12, the role of the stringed instrument * * * box: make the sound louder.

13. There are three methods to control noise: sound source control, sound propagation path control and sound reception control.

14, the luminous object is called a light source. Light travels in a straight line.

15. When light strikes the surface of some objects, the route of light will change. This phenomenon is called light reflection. Different objects have different reflective abilities.

16. The functions of convex lens are: focusing, magnifying and imaging.

17, sunlight is composed of seven colors of light. They are: red, orange, yellow, green, blue, indigo and purple.

18, ordinary white light (such as sunlight) consists of seven colors. Different objects will absorb and reflect different colors of light. For example, a red flower only reflects red light, and all other light is absorbed by it.

15, red, green and blue are three basic colors, which are collectively called the three primary colors of light. All colors of light are composed of these three colors of light, and color TV uses this principle.

Verb (abbreviation for verb) machinery and force

1. Tools or devices used to save labor or facilitate work are called machines. Everything from needles to aircraft carriers is mechanical.

2. Conditions for balance of lever ruler: (left) number of squares x number of hooks = (right) number of squares x number of hooks.

3. Lever is a simple machine with the earliest invention and the widest application.

4. When the distance from the force point to the fulcrum is greater than the distance from the key point to the fulcrum, it is a labor-saving lever;

When the distance from the force point to the fulcrum is less than the distance from the key point to the fulcrum, it is a laborious lever;

5. When the distance from the force point to the fulcrum = the distance from the key point to the fulcrum, it is a lever that is neither labor-saving nor laborious.

6, labor-saving lever costs distance, and labor-saving lever saves distance.

7. A wheel with small teeth on the edge is called a gear.

8. A wheel with a groove on the edge of the rope is a pulley.

9. A pulley that is fixed in one place and cannot move is called a crown block; The crown block can change the direction of force, but it can't save effort.

10, the pulley that moves with the weight is called the moving pulley; Moving pulley can save labor and cannot change the direction of force.

1 1, the pulley block is labor-saving and convenient.

Power is everywhere. Pushing, pulling, lifting, pressing, sucking and repelling between objects are all forces. Force can change the motion state of an object. Force has not only magnitude, but also direction.

13. dynamometer: an instrument used to measure force. The "n" marked above is the symbol of the unit of force "Newton" (abbreviated as "cow").

14 Like a piece of wood, an object immersed in water will be pushed upward by water, which is called buoyancy. Objects that float on water and sink to the bottom are buoyed by water.

15. When an object is subjected to an external force, its shape will change, and at the same time it will produce a force to resist deformation, which is called elasticity. When the external force disappears, they will return to their original state. This property of an object is called elasticity.

16, within the elastic limit, the greater the change of object shape, the greater the elasticity.

17. When an object slides on the surface of another object, the force that prevents it from sliding is called friction. The uneven surface is the cause of friction. Friction between objects is related to roughness of contact surface and pressure between objects. Friction has both advantages and disadvantages for us.

18, the forces we know are: gravity, elasticity, friction, wind, water, buoyancy, recoil, magnetism and so on.

19, the pendulum swings once. The longer the swinging rope, the slower the swinging speed.

20. In China, water clocks are also called "carved leaks" and "leaky pots". According to the working mode, it can be divided into two types: one is to record the water leakage time (drainage type), and the other is to record the water injection time (receiving type).

2 1, pendulum clock is made by using the property that pendulum can swing regularly; The water clock is made by using the relative stability of water flow under the same conditions; Quartz watches use timely crystals in the circuit, which can produce vibration with stable frequency. People invented various clocks and watches by using the relatively stable motion laws of some objects.

22. Both animals and humans have biological clocks. People's biological clocks are varied, and their body temperature, blood pressure, pulse, mood, physical strength and intelligence all change periodically. The biological clock has a great influence on human health.

Intransitive verbs air and water

Air is a mixture. It is mainly composed of nitrogen, oxygen, carbon dioxide, water vapor and other gases. By volume, nitrogen accounts for about 78%, oxygen accounts for about 265,438+0%, and other gases including carbon dioxide and water vapor account for about 65,438+0%.

2. Oxygen can support combustion and is soluble in water. (Slightly soluble in water)

There is little carbon dioxide in the air. It is heavier than air, does not support combustion and is easily soluble in water. Under pressure cooling, it can form a solid like snow, called dry ice. Dry ice can be used to refrigerate goods, carry out artificial rainfall and simulate clouds on the stage.

The temperature of air is called temperature. The commonly used degree day is "Celsius", which is represented by the symbol "0C".

5. Measure the temperature with a thermometer: ① Hang the thermometer in an outdoor ventilated place, out of direct sunlight; ② The thermometer is about 1.5m high from the ground; (3) When reading, keep the thermometer vertical and the line of sight is flush with the top of the thermometer liquid column.

6. The heat energy of the sun makes the air on the earth flow and forms the wind. Wind is caused by regional temperature differences.

7. Wind is flowing air. The direction of the wind is determined as the wind direction. The power of wind is called wind power. The faster the wind, the stronger the wind. People generally divide the wind power from small to large into 0 to 12 and *** 13.

8. The wind vane measures the direction of the wind; An anemometer measures the wind.

9, the wind is good for people, but also has disadvantages.

10. Tornado is a cyclone with strong wind and small scope. From a distance, it looks like a wobbly elephant's nose.

1 1, meteorological index, is the impact of meteorological conditions on the environment.

12, March 23rd every year is World Meteorological Day. "Meteorology" refers to wind, clouds, rain, snow, thunder, fog, lightning and other phenomena that occur in the atmosphere. "Weather" refers to the comprehensive situation of various meteorology in a short period of time.

13, water of rivers, lakes and seas. Evaporate, turn into steam, and rise to the sky. Water vapor turns into water droplets when it is cold. If the temperature in the sky is below 0 degrees Celsius, water vapor will become small ice crystals. Countless small water droplets or small ice crystals gather together to form clouds. Fog and clouds are formed by condensation of water vapor.

14, water will become steam when heated, and water will become water when steam is cooled.

Water has three states: liquid, solid and gas. Common solid water is ice, frost and snow. Gaseous water, also called steam, is invisible to our naked eyes.

16. Usually when water is heated to 1000C, it will suddenly turn into steam, and the temperature at this time is called the boiling point of water.

17. Generally, when the cooling temperature drops to 00C, water will start to freeze, and when the heating temperature rises to 00C, ice will start to turn into water. So 00C is the freezing point of water.

18, and the number of clouds occupying the sky area is called "cloud amount".

19, "Rainfall" is the depth of rain falling on the horizontal ground in a certain period of time, usually in millimeters (mm). It can be measured with a rain gauge.

20. The phenomenon of "disappearing" in water like salt is dissolution. Stir, heat, etc. Can accelerate dissolution.

2 1. After water is left standing for a period of time, some insoluble impurities will sink to the bottom layer, which is precipitation. Adding alum or other coagulants to water can accelerate the precipitation of impurities.

22. Boiling is a common, simple and reliable disinfection method.

23. Methods of purifying water: sedimentation, filtration and disinfection.

VII. Human health

1. Cells are the basic units of organisms. Cells are alive.

2. The fetus grows up slowly in the womb. There is an umbilical cord in the uterus, which gives the nutrition and oxygen in the mother to the baby inside.

3. People's growth stages are usually divided into: infancy (0~3 years old), infancy (3~6 years old), childhood (6~ 12 years old), adolescence (12~ 15 years old) and adolescence (15 years old).

"Brothers with five senses" refers to the five sensory organs of human beings, namely, eyes (seeing), nose (smelling), ears (hearing), tongue (tasting) and skin (touching).

5. The nervous system includes: brain, spinal cord and nerves.

6. The human digestive system includes: mouth, esophagus, stomach, liver, small intestine, large intestine and anus.

7. The respiratory system includes nose, pharynx, larynx, trachea, left and right bronchi and lungs.

8. When we breathe, we breathe in oxygen in the air and exhale carbon dioxide. Carbon dioxide can make clear limewater turbid.

9. The human circulatory system consists of heart, blood vessels and blood.

10, common food additives are: pigment, essence, saccharin, preservative, puffing agent, etc. Excessive use of synthetic additives can lead to allergies, deformities and canceration.

1 1. The essential nutrients in food mainly include protein, starch, sugar, fat, vitamins, minerals and cellulose.

12, starch turns blue when it meets iodine.

13, green food refers to: safe, nutritious and pollution-free food.

14, bottled wine, vinegar and soy sauce in plastic drinks are not suitable.

15, people use magnifying glasses and microscopes to observe things that are not clear to the naked eye.

16, teenagers in China generally enter puberty from 10- 12. The first physiological change in adolescence is the rapid growth of height and weight; The second physiological change is the appearance of secondary sexual characteristics.

17, heredity and variation are one of the most basic characteristics of life.

18, heredity: children always keep some characteristics similar to their parents. This phenomenon is heredity.

19, variation: children will have some differences with their parents, and some are even very obvious. This phenomenon is mutation.

19, "cloning" means: asexual reproduction. The phenomenon that an organism expands and reproduces by a small part of itself is asexual reproduction. Dolly the cloned sheep has three mothers. Without heredity, there is no continuation of species; Without variation, the world would not be so colorful.

Eight, biological (animals, plants, microorganisms)

1 Like ants, the body consists of three parts: head, chest and abdomen. Animals with a pair of antennae on their heads and three pairs of feet (some with two pairs of wings) on their chests are called insects.

Butterfly life: egg, larva, pupa, adult, and then spawn.

3. Butterflies are changed from caterpillars. It has a pair of compound eyes, consisting of more than 15000 small eyes.

The same characteristics of fish are: scales on the body surface, breathing with gills, swimming with fins, breeding offspring with eggs, and living in water all their lives.

5. Water quality, water temperature and stocking density are important factors affecting the life of goldfish.

6. Animals that are hairy, viviparous and fed on their mothers' milk are all mammals. Most mammals are color blind.

7. Flying mammalian bats; African cheetah, the fastest animal; The biggest animal, the blue whale.

8. Frogs are amphibians. Amphibians are signs of good or bad environment, which scientists call "indicator organisms".

9. About 230 million to 65 million years ago, dinosaurs thrived and ruled the earth for 65.438+65 million years.

10, almost all creatures in nature have a direct or indirect food relationship with a certain number of other creatures, which is called food chain.

1 1, sunlight, water, oxygen, food and so on constitute the environment on which animals live.

12, animal hibernation is a kind of protective behavior against bad environment. The main factors causing hibernation are the decrease of environmental temperature and the lack of food.

13. Animals spend the winter by hibernating, preparing food, flying south and molting.

14, Darwin, a great British scientist, his scientific masterpiece "The Origin of Species". The core view of "evolution": natural selection, survival of the fittest.

15, seed germination needs: air, temperature, water.

16, sunshine, water, air, etc. It is a condition for plant growth.

17. A complete plant generally consists of six parts: roots, stems, leaves, flowers, fruits and seeds. Roots absorb water and nutrients; Stems carry water and nutrients.

18. Plants whose life span is less than one year are called annuals. Plants that can prey on small insects are called insect-eating plants.

19. Fruit consists of pericarp and seeds.

20. Photosynthesis: Under the action of sunlight, the green leaves of plants use carbon dioxide and water to synthesize carbohydrates and produce oxygen.

sunlight

Water+carbon dioxide carbohydrate+oxygen

green leaves

2 1, the stems and leaves of plants have phototropism characteristics; The roots of plants have hydrotropism and geotropism.

22. The photosynthesis of plants is the endless power of all life on the earth.

23. Bacteria are a large category of microorganisms, which have many forms such as sphere, rod and spiral.

24. Microorganisms include viruses, bacteria, actinomycetes and fungi.

25. Microorganisms are tiny and simple in structure.

26, germs, bacteria and fungi are collectively referred to as microorganisms.

27. Microorganisms play an important role in material transformation and circulation in nature.

Nine, scientific inquiry methods

1, guessing is just a possible answer, which is not always the same as the fact. If you want to know whether this conjecture is correct, you must try to verify it.

2. Classification is an important research method. Different classification standards lead to different classification results.

3. Field investigation is an important scientific research method.

4. Generally, an experimental variable is set in the comparative experiment, that is, only one condition is changed in the comparative experiment.

5. The basic ways to collect facts and evidence are: consulting books, searching online, investigating, visiting, observing records, doing experiments, etc.

6. People often use models to explain all complex, invisible or incomprehensible things and phenomena. When expressing and communicating, the successful application of the model can often get twice the result with half the effort.

7. Argumentative essay: It is to explain one's own thoughts and opinions according to a certain question, and to analyze and refute others' opinions. Debate can be divided into theme debate, role debate and so on.

8. Scientists' research conclusions are not always correct, but their research methods are worth learning.

9. The process of scientific inquiry is the process of constantly discovering, asking and solving problems.

10. There is no fixed format for writing small papers, and it is generally carried out according to the steps of asking questions, putting forward assumptions, researching and analyzing, and drawing conclusions.

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12. A complete survey report generally includes: class, name, investigator, survey content, survey object, survey purpose, survey time, survey place, survey method, survey process, survey results and suggestions.

13. A relatively complete investigation report generally includes: investigation time, investigation place, investigation personnel and division of labor, investigation purpose, investigation method, investigation process and investigation conclusion.