Why does scientific sorbet get angry? The reason why sorbet bubbles is because there is a lot of invisible water vapor in the outside air. When it comes to cold sorbet, it will liquefy into droplets when it is cold. It seems that the sorbet is bubbling.
Why do sunflowers always face the sun? Sunflower stems contain a wonderful auxin. This auxin is very afraid of light.
When it is illuminated, it will go to the backlight side, and the cells on the backlight side will multiply rapidly. Therefore, the backlit side will grow faster than the bright side, which will bend the sunflower to light. Why does cicada shed its skin? Cicada's shell (exoskeleton) is hard and can't expand with the growth of cicada. When the cicada grows to a certain stage, the cicada's exoskeleton restricts its growth, and the cicada loses its original exoskeleton, which is cicada slough.
How do bees make honey? First, the bees spit the sweet juice of the flowers they picked into an empty hive. At night, they suck sweet juice into their honey stomachs to make it, and then spit it out and swallow it. It takes 100~240 times to make sweet honey. How do birds sleep? During the day, birds shuttle in the branches, chirp and fly freely under the blue sky. At night, they should rest, sleep and recover their strength like us, but the sleeping posture is different! Beautiful mallard ducks and swans hunt and play in the water during the day, but they can't rest when they leave their favorite water at night.
They bend their beautiful long necks, bury their heads in their wings, and then let themselves float on the water, dreaming a beautiful dream, drifting with the tide, very leisurely. Long-legged birds such as cranes, storks and herons always sleep independently on one foot, and when they are tired, they change their other feet, which is a model of combining work and rest.
Partridges like to form a big circle in groups when resting, and then their heads are outward and their tails are inward. In this way, no matter which direction the enemy attacks, they can find and escape in time.
Birds with sweet voices, such as blackbirds and larks, usually bend their legs when sleeping, and their claws bend to firmly grasp the branches without worrying about falling from the trees. And the owl, a "night-shift" raptor, you can always see it standing on a dense branch with one eye open during the day, actually sleeping.
Isn't the owl's sleeping position very different? Is to always monitor the surrounding environment and guard against enemy attacks! = = = = = = = = = = = = = = = = = = Will the fish drown? Fish has gills and can breathe in the water, while fish has swim bladder and can float freely in the water. However, some people say that fish living in water will also drown. Is it true?/You don't say. It sounds ridiculous, but it's true.
The swim bladder is the "lifebuoy" for fish swimming, and it can adjust the specific gravity of fish by inflating and deflating. In this way, when swimming, the fish can maintain a stable state, will not sink or float in the water, and the muscle activity is minimal.
However, when the fish sinks to a certain depth (that is, the "critical depth"), the huge external pressure will make the volume of the swim bladder irreparable. At this point, its buoyancy is less than its own gravity, so it will involuntarily sink to the bottom of the water, can not float up again, and will eventually drown because it can not breathe.
Although fish can still float upward by swinging their fins and tails, it won't help if they sink too deep. On the other hand, fish living in the deep sea can live freely in the deep water because their bones can bear great pressure.
If we quickly let the fish living in the deep sea reach the "critical depth", it will continue to "swell" until it comes to the surface because the pressure inside its body cannot be balanced with the smaller pressure outside. Sometimes, it even spits out its internal organs and "explodes" to die.
= = = = = = = = = = = = = = = = = = Greedy children become stupid. Gluttony will reduce the blood flow to the brain. If you eat too much at a time, or eat all the time, you will mobilize a lot of blood in the human body, including blood in the brain, to the gastrointestinal tract. Adequate blood supply is the premise of development, and if it is often in ischemic state, its development will inevitably be affected.
Gluttony will lead to overeating in the "obese brain", especially if you eat too much nutritious food, the calories you consume will greatly exceed the calories you consume, and the heat energy will be converted into fat and accumulated in the body. If there is too much fat in brain tissue, it will cause "brain obesity".
Studies have confirmed that human intelligence is related to the number of wrinkles in the sulcus gyrus of the brain. The more obvious the sulcus gyrus, the more wrinkles and the higher the intelligence level. The obese brain makes the sulcus close, wrinkles disappear, the cerebral cortex is smooth, the neural network is poorly developed, and the intelligence level will be reduced.
Overeating can inhibit the physiological function of the intelligent area of the brain. The way of human brain activity is that excitation and inhibition induce each other, that is, when some parts of the brain are excited, some areas of its adjacent parts are in a state of inhibition. The stronger the excitement, the deeper the inhibition on the surrounding parts, and vice versa. Therefore, if the autonomic nerve center responsible for gastrointestinal digestion is excited for a long time because of overeating, it will inevitably lead to the suppression of adjacent brain intelligent areas such as language, thinking, memory and imagination.
If these areas are often suppressed, their intelligence will get worse and worse. Overeating can damage the brain because of constipation. Snacks for children are mostly high-nutrient fine foods, which are easy to constipation.
When constipation occurs, the metabolites accumulate in the digestive tract for a long time, and after the action of intestinal bacteria, a large number of harmful substances are produced, which are easily absorbed by the intestine and enter the blood circulation, causing chronic poisoning of brain nerve cells and affecting the normal development of the brain. Overeating can also promote premature aging of the brain. In a study, scientists found that a substance that can promote premature aging of the brain-fibroblast growth factor, will increase tens of thousands of times after meals because of overeating. This is a substance that can promote arteriosclerosis, so overeating will cause premature aging of the brain in the long run.
Simple and easy-to-learn scientific knowledge The mystery of automatic rotation: Why do cartons filled with water rotate? Materials: empty milk cartons, nails, 60 cm long rope, sink, water operation: 1. Punch five holes in the empty milk box with nails. 2. One hole is in the middle of the top of the carton, and the other four holes are in the lower left corner of the four sides of the carton. 3. Tie a rope about 60 cm long on the top hole. 4. Put the paper box on the plate.
2. Earth science knowledge essay 200 words grade three
science
Real science can benefit mankind, while pseudoscience will bring disaster to one side. We study science in order to promote human progress, so we should have a kind and harmonious heart, keep an indifferent and peaceful heart to face science, be kind to science and make good use of it. Finally, I hope everyone can love science, learn science and use science. As long as we study hard and never give up, we will get real science.
One by one, whimsy makes "impossible" a reality, which is the clever use of scientific knowledge by human beings. All scientists have made great discoveries since childhood, and the door of science is always open to children who love to explore. Students, you also strive to make the impossible possible and make our life more exciting!
Walking into science, there are many wonderful things in the scientific community. Observing meteorology, collecting specimens, scientific experiments, popular science activities, life discovery, etc. It's all an exploratory science. Human beings make progress because of science, and science innovates because of human beings. Human can't live without science, and science can't live without human.
3. Little scientific knowledge
Hello, my friend, Mpamba's question-the mystery that boiled water freezes before cold water. If I ask you, "If the same amount of boiling water and cold water are put into the refrigerator, which one freezes first?" You will probably sneer and answer, "Cold water, of course!" No! 1. The physical problems of Mpamba There is a student named Mpamba in the third grade of Magamba Middle School in Tanzania. At school, he often makes ice cream with his classmates.
What they do is boil raw milk, add sugar, cool it, then pour it into ice cubes, and then put it in the freezer for freezing. Because there are many students in the school, the location of the freezer has been in short supply.
1963 One day, when Mpamba came to make ice cream, there was not much space in the freezer. In order to get ahead of him, a classmate added sugar to the raw milk, immediately put it in the ice and sent it to the freezer of the refrigerator.
Mpamba must boil the milk, add sugar and wait until it cools. Immediately, he poured the boiled milk into the ice and sent it to the freezer of the refrigerator. A miracle happened. An hour and a half later, Mpamba found that his hot milk had been frozen, while another glass of cold milk was still sticky and not frozen. This phenomenon surprised Mpamba! 2. Laughing and answering Mpamba's riddle, he asked the physics teacher: Why does hot milk freeze before cold milk? The teacher's answer is: "You must be mistaken, such a thing can't happen."
Mpamba didn't stop there. He firmly wrote down this unusual phenomenon and was often lost in thought ... Mpamba later went to Mukwa High School in iringa. He did not forget this question and asked the physics teacher in high school: "Why do hot milk and cold milk put in the refrigerator at the same time, and the hot milk is frozen first?" He didn't expect the teacher to laugh at him like this: "The answer I can give you is: You must be wrong." When he continued to ask questions and argue with the teacher, the teacher sneered, "This is Baba's physics problem."
Mpamba couldn't figure it out and was not satisfied, but he didn't dare to contradict the teacher. Finally, an excellent opportunity came. Dr Osborne, head of the Department of Physics at Dar es Salaam University, visited Mkwa High School.
Dr Osborne finished his academic report to the students, and then he answered their questions. After full brewing, Mpamba summoned up his courage and asked him a question that he had been thinking about for many years: If you take two similar containers, put the same volume of water, one at 35℃ and the other at 100℃, and put them in the refrigerator at the same time, the water at 100℃ will freeze first, why? Dr Osborne accepted a serious "examination paper" in front of George W. Mpamba, which is the first time he heard of this unusual phenomenon.
The embarrassed and confused doctor didn't hide anything, but replied realistically, "Well, I don't know, but I promise that I will do this experiment myself after I return to Dar es Salaam." After he came back, he immediately did the experiment with his assistant.
It turns out that what Mpamba said is a true fact! What the hell is going on here? Why is this happening? 1969, an article written by Mpamba and Osborn was published in the British magazine Physics Teacher. This paper makes a detailed experimental record of "Mpamba's physical problems" and tries to explain the causes of the problems for the first time. They did a series of experiments.
The experimental object is a borosilicate glass beaker with a diameter of 4.5 cm and a volume of 100 ml, in which 70 ml of boiling water at various temperatures is placed. Through the quantitative analysis of the experimental results, it is concluded that the cooling mainly depends on the liquid level; The cooling rate depends on the surface temperature of the liquid, not its overall average temperature; Convection inside the liquid keeps the surface temperature of the liquid higher than the body temperature (assuming the temperature is higher than 4℃); Even if two cups of liquid are cooled to the same average temperature, the heat loss of the primary heating system is still much higher than that of the primary cooling system. The liquid must go through a series of transition temperatures before freezing, so it is obviously not enough to describe the state of the system with a single temperature, which also depends on the temperature gradient of the initial conditions.
Although Dr. Osborne did not finally solve Mpamba's physical problems, he gave Mpamba Jr and us a scientific and realistic answer sheet in the face of science and facts. This problem is far more complicated than imagined. Later, many people did a lot of experiments and research in this field. Finding this seemingly simple problem is actually much more complicated than we thought. It involves not only physical reasons, but also the role of microorganisms as crystallization centers. It is an out-and-out "multivariable problem".
(1). Physical reasons Physically speaking, refrigeration has four coexisting mechanisms: radiation, conduction, vaporization and convection. Through experimental observation and comparison of results, it is found that the main reason why hot water freezes before cold water is the comprehensive effect of conduction, vaporization and convection interaction.
If we describe the freezing process of hot water and cold water and analyze the reasons, it will be more telling: a cup filled with cold water with an initial temperature of 4℃ will freeze for a long time, because water and glass are both substances with poor thermal conductivity, and it is difficult to effectively transfer the heat inside the liquid to the surface through conduction. As the temperature drops, the volume of water in the cup expands, the density decreases and accumulates on the surface.
Water freezes on the surface first, and then extends to the bottom and around, forming a closed "ice shell". At this time, the water in the inner layer is isolated from the outside air and can only dissipate heat through conduction and radiation, so the cooling rate is very small, which prevents or delays the normal decline of the water temperature in the inner layer.
In addition, due to the volume expansion of water when it freezes, the formed "ice shell" also plays a certain role in inhibiting further freezing. A cup filled with hot water with an initial temperature of 100℃ takes much less time to freeze. What we see is that the ice layer on the surface can never be connected into an ice sheet, and we can't see the phenomenon of "ice shell" formation, but needle-like ice crystals grow into the liquid along the ice-water interface (this phenomenon can't be seen when the initial temperature is lower than 12℃).
With the passage of time, the ice crystals turn from fine to coarse, because the hot water with higher initial temperature becomes denser and flows downwards after cooling, forming convection in the liquid and surrounding water molecules.
4. What scientific knowledge is there in Grade Three?
The Complete Works of Scientific Knowledge Points in Grade Three (Volume I, Education Edition)
Unit 1 Plant Review Outline
1, (see), (listen), (touch), (ask), (measure) and (smell) are all basic methods of scientific observation.
2. The characteristics of a big tree can be described by its height, crown shape, trunk thickness, bark appearance and leaves appearance.
3. The main difference between a big tree and a small grass is that the height of the plant is different, the thickness of the stem is different, the texture of the stem is different and the life span is different.
4. Trees and grass are similar in that they both grow in (soil), have (green) leaves and need (water), (sunlight) and (air).
5. The swollen sponge in the petiole of water hyacinth is full of air, which is why it floats on the water.
6. Both aquatic plants and terrestrial plants have organs such as (roots), (stems) and (leaves). Their growth needs (water), (sunlight) and (air).
7. Aquatic plants include (water hyacinth), (Ceratophyllum), (Alternanthera philoxeroides) and (duckweed).
8. Similarities between water hyacinth and Setaria viridis: growth needs (moisture), (sunlight) and (air); There are (roots), (stems) and (leaves); Metropolis (breeding offspring); Life span (short); They are all (herbs).
9. Leaves of plants are generally composed of (leaves) and (petioles). There are veins on the leaves.
10, leaves are alive, and they have to go through the process of germination, tender leaves, old leaves and dead leaves.
5. For the popular science knowledge in the third grade of primary school, it is best to send handwritten pictures, which should be clear.
Dust is annoying to everyone, and it is harmful to the environment? Health is harmful to human health. Therefore, throughout the ages, people have always been "diligent, not dusty." However, have you ever thought that human beings can't live without dust? If there is really no dust in nature, what kind of situation will we face?
The diameter of dust particles is generally between one ten thousandth and one millionth of a millimeter. The dust that the human eye can see is a giant in the dust, and the tiny dust can only be seen under a high-power microscope. The main sources of dust are soil and rocks. After weathering, they split into fine particles. These particles float in the air with other organic particles. They absorb some sunlight and reflect it around, just like countless point light sources. The sunlight is greatly weakened by the reflection of dust, so it becomes soft. If there is no dust in the atmosphere, strong sunlight will make people unable to open their eyes.
Interestingly, dust particles also have a "strange temper", which tends to reflect purple, blue and cyan light with shorter wavelengths, and "likes" to absorb other colors with longer wavelengths. The sky we see on the ground is blue because of the high dust content in the lower atmosphere. If there were no dust in the atmosphere, the sky would be white.
Most dust is hygroscopic. Water vapor in the air must adhere to dust to condense into small water droplets. In this way, when the water vapor in the air reaches saturation, the dispersed water vapor will adhere? Dust forms stable water droplets that can float in the air for a long time. If there is no dust in the air, everything on the ground will be wet. What's more, there can be no clouds in the sky, and it is impossible to form rain and snow to adjust the climate, so it is impossible for water evaporated from the ground to return to the ground. If there is less and less water on the earth and it dries up completely, living things can't survive. In addition, due to the refraction of sunlight by these water droplets, there will be colorful natural scenery such as sunset glow, idle clouds and rainbow halo from Zhao Hui. If there were no dust in the air, how monotonous nature would be.
6. Primary school students have simple scientific production in the third grade, and they have it at home.
Activity preparation:
1. Story activity teaching aid, animal pictures, insect pictures.
2. Enrich the knowledge about insects, beneficial insects and pests in advance.
3. Various materials for making cobwebs, perforated cardboard, paper ropes or hair roots.
4. Use children's imagination (or be guided by adults)
Let children stimulate curiosity according to the finished product and guide them to move on when they are almost finished. When children really finish a finished product by themselves, they will have a great sense of accomplishment.
7. The composition of popular science knowledge in the third grade of primary school is about three or four hundred words.
On Sunday, I listened to English on the repeater, but my voice became louder and louder. I looked up and there was no electricity. I just wanted to ask my mother for money to buy a battery, but then I thought, one battery, 1.5 yuan, four at a time, and the new battery was running out; In addition, abandoned batteries will pollute the environment ... by the way, I have read about the reuse of old batteries in books before. Why don't I try? So I went to the bookcase and rummaged through the books. At this time, my mother came over and asked, "Yang Yang, why don't you listen?" "Oh, the battery is dead." "Then buy two festivals!" "No, I want to make my own battery." My mother looked at me incredulously and said, "You are daydreaming!" "Just watch!" Finally, I found this book. According to the method introduced in the book, I found four old batteries, scissors and nails, and made some fertilizer from flower fertilizer. In order to persuade my mother, I specially asked her for help. First, I peel off the skins of the four batteries with small scissors (don't damage the prototype of the battery), then I use small nails to make holes in the battery surface, pour fat water into it, and then seal the holes with wax. So it's over. I put the battery in the repeater. Although there is electricity, the power is too small. I think there is probably too little fat and water. I did it again, but not yet. What's the problem? On second thought. My mother smiled and said, "I said no, you see, it failed!" " "I am not reconciled, thinking: the electricity for making batteries comes from fertilizer water. Can you exchange it for other raw materials?
Later I injected saline in the same way. The repeater was fully charged and took a long time. Mom saw it and said happily, "Haha, the battery factory is going to close down!" " "
It seems that waste is not necessarily useless!
8. Seek the knowledge summary of the third grade of primary school science.
1 method, (see), (listen), (touch), (ask) and (measure) are all basic methods of scientific observation.
2, in the process of observation activities, let students (learn to study in groups), (communicate), (express), (discuss), (record) and other learning methods. 3. The characteristics of a big tree can be described by its height, crown, trunk, bark and leaves.
Grass, like trees, has the same characteristics as life. 5. The main differences between trees and grass are: the height of plants, the thickness of stems and the texture of stems.
6. The similarity between a big tree and a grass is that they both grow in (soil), have (green) leaves and need (water), (sunshine) and (air). 7. The swollen sponge in the petiole of water hyacinth is full of air, which is why it floats on the water.
8. Aquatic plants have organs such as (roots), (stems) and (leaves). Their growth needs (water), (sunlight) and (air).
9. Aquatic plants include (water hyacinth), (Ceratophyllum), (Alternanthera philoxeroides) and (duckweed). 10, similarities between water hyacinth and Setaria viridis: growth needs (moisture), (sunlight) and (air); There are (roots), (stems) and (leaves); Metropolis (breeding offspring); Life span (short); They are all (herbs).
1 1, the leaves are (diverse), and the leaves of the same tree have (* * * the same) basic characteristics. 12, the leaves of plants are generally composed of (leaves) and (petioles).
There are veins on the leaves. 13. The leaves are alive. They grow from (leaf buds) and finally get old (die) to complete their life.
14. Plant changes are mainly manifested in (germination), (growth), (flowering) and (fruiting). 15, the size of leaves can be compared by (measurement), and the changes of plants can be recorded by (data).
16. Plants can be divided into (terrestrial) plants and (aquatic) plants according to different living environments. 17, the survival needs of plants (water), (sunlight), (air) and (nutrition).
18, plants have a life cycle, and each plant has a certain life span. 19, the same characteristics of plants are: growing in a certain environment; Needs (moisture), (sunlight), (air) and (nutrition); Metropolis (growth and development); Metropolis (breeding offspring); There is a process from birth to death.
20. The typical growth stages of sunflower are: (germination), (growth), (flowering) and (fruiting). Education Press Science Three Animals Review Outline Unit 2 1. Animals have (diversity), their survival depends on (environment), and different environments grow different (animals).
2. When we observe snails, we should pay attention to their (appearance), (life), (movement), (reaction), (feeding), (excretion) and (reproduction). Snails can use (stomach foot) to crawl on various objects.
Snails can respond to the outside world. Such as (antenna extension) and (fuselage contraction) in the housing.
Earthworms like to live in dark and humid environment. 6. The earthworm's body consists of many parts, including (mouth), (girdle) and (* * *).
7. Snails and earthworms are similar in that they both adapt to (wet) environment, have soft bodies, can crawl, eat (food), excrete and reproduce. The body of an ant is divided into three parts: (head), (chest) and (abdomen). There are a pair of tentacles on the head and six feet on the chest.
9. Ants adapt to life on land. 10. Characteristics of ants: they live on land, have three parts (head, chest and abdomen), have six feet, can move (crawl), live in groups, have diverse foods and can reproduce.
1 1. Fish has the basic characteristics of life and can adapt to the aquatic environment. 12, goldfish is characterized by: living in (water), having (scales) on its body surface, swimming with (fins), breathing with (gills), eating (fish food) and (debris), and being able to (reproduce).
13, ants and goldfish have something in common: both have (life), energy (exercise), need (food) to maintain growth, energy (excretion), energy (reproduction) and so on. 14. Different individuals (forms) of animals have different living environments.
15. Animals have the same characteristics: living in a certain environment, exercising, needing (food) to maintain growth, excreting waste, reacting to the outside world (reaction), meeting (growth and development), meeting (reproduction) and so on. Review Outline of Unit 3 of Science 3, Education Press 1. Everything is made of one kind (material) or many kinds, and there are many different kinds (materials) around us.
The common materials around us are (wood), (fiber), (paper), (glass), (steel), (plastic) and (rubber). 3. Know what things around you are made of.
4. Describe the wood with proper words: (yellow and white, with lines on the surface, not too heavy, capable of cutting, sawdust after sawing, capable of floating on water ...) 5. Metal is a very important material and has many important uses. 6. Characteristics of metals: (hardness), (metallic luster), (ductility), (easy heat transfer), (conductivity), (poor water absorption), etc.
7. Flexibility refers to the nature of an object after deformation (not easy to break). Physical properties can be used to describe materials, such as hardness, elasticity, water absorption and fluctuation in water.
8. Characteristics of plastics: It has the characteristics of (flexibility), (insulation), (corrosion resistance), (heat transfer is not easy), (light weight) and (reusable). 9. Different materials have different ups and downs in water.
10. Wood characteristics: (light weight), (relatively hard), (easy to process), (elastic), (floating on water), (bearing capacity), etc. 1 1. Bricks are mainly used for building houses, and ceramics are mainly used for making daily necessities.
12. Bricks are made of (clay). 13. Ceramics are made of a special kind of clay.
14, we use some natural materials, such as (wood), (clay) and (cotton).
9. The third grade of primary school is in urgent need of scientific composition.
My mother once told me such a riddle: "Zhuge Liang in Nanyang, sit tight." Arrange the eight diagrams and catch the flying generals. "This myth tells us that spiders only eat living things, but don't they eat dead things? This aroused my interest and I did the experiment.
I caught a little spider from the corner and put it in a box (with holes around it and glass on it for easy observation). Before the spider could weave a web, I picked up a dead bug and a dead fly and put them in front of the spider. The spider ignored them, then hit the box with her hand, and the spider crawled in other directions.
In order to find out whether spiders eat dead flies completely, the next day, I came to the box to observe and saw that dead insects and dead flies were still in their original places, but there was a net in the corner of the box, and the spider was lying quietly on the net. At this time, I thought: Is it because there is no net that the dead flies and insects didn't eat it yesterday? So I picked up the dead fly and gently put it on the net, but the spider still didn't move. Then, I gently touched the edge of the net with my pen. Gee, the spider seems to have a reaction and started to climb in a trembling direction. I took the pen back and the net stopped shaking. The signal was interrupted and stopped. Soon, the spider climbed to the center of the web again. I touched the dead fly's body on the net with the pen tip again, and the net began to vibrate, and spiders began to crawl here. I took back the nib again and the spider stopped. Like last time, after a while, the spider climbed to the center of the web again. Oh! I finally understand that spiders feel by the vibration of their webs and prey by weaving them. So, I recorded the experimental results.
In order to prove that spiders feel through the vibration of their webs, I did another experiment. Put the pen tip on the dead fly on the net and vibrate for a long time. The vibration of the web is getting bigger and bigger, and the spider seems to feel stronger and stronger. Spiders will come in a hurry. When a spider meets a fly, I will take back the pen tip, only to see that the spider's tail will soon spit out sticky silk to tie the fly, and then look at the spider's back, as if sucking the fly. Soon, there was a complete empty shell left on the Internet. This experiment proves that spiders eat moving insects.
Our secret group went to the library and bookstore to consult a lot of books about spiders. Among them, General Zoology wrote that spiders are carnivores, and their food is mostly insects or other arthropods. But your mouth has no upper jaw, so you don't swallow solid food directly, but suck it slowly. When insects and other animals come into contact with the net, they will struggle desperately on the net to make the net silk vibrate, so that spiders will find it soon. Spiders will crawl along the longitudinal silk to their prey, wrap the prey with spider silk and fix it on the net. First, the venom secreted by poisonous glands in claws is injected into the captured prey to kill it, then the digestive enzyme secreted by midgut is injected into the captured tissue torn by claws, which is quickly decomposed into juice, then inhaled into digestive tract, and finally eaten the remaining body shell. These fully prove that flying insects make the spider's web vibrate, and the web vibration will make it feel, and the spider will catch its prey if it feels. So it is confirmed that spiders only eat live animals, not dead insects.