A science problem with the help of the experts .

In 1953, Miller simulated the primitive earth's atmosphere and found that under the action of thunder and lightning, these inorganic atmospheric components can be synthesized into organic amino acids and other constituent components of life, thus providing an experimental basis for the theory of life autopoiesis. However, the above discoveries not only do not support this theory, but are skeptical of the above theory to a certain extent, because amino acids and other organic matter have also been found in the universe outside the earth, and at that time, these "small stars" containing amino acids were very likely to bring these organic matter and even life to the earth through collision or fall on the earth's surface, so the origin of life on the earth is still a scientific puzzle whether the earth was born on earth or came from other places. However, I am more inclined to the autopoiesis theory, because the theory of cosmic life (which holds that life on earth comes from the universe) does not fundamentally solve the problem of the origin of life, because if life on earth comes from the universe, then what about the life of the universe from **?

The theory of life in the universe pushes the origin of life into an ethereal place, and if life on the earth comes from the universe and is due to the collision of planets in the universe, then other planets have the same "life-receptive" characteristics as the earth, why has human beings not found life on planets other than the earth until now? Why did those meteorites that carried life fall to Earth impartially?

None of them are supported, frequent collisions of celestial bodies, and extremely high temperatures on the earth's surface are not enough for primitive life to be born.

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Problem description: Is it true or false that water can dissolve some solids, but not some gases and liquids? After the rock sugar is dissolved in water, the rock sugar does not exist, right or wrong? Put some lard in the hot vegetable soup, and the lard will dissolve, is this also a dissolution phenomenon, right or wrong?

When the water evaporates, the substance dissolved in the water disappears, right or wrong? Is it true that anything that cannot be dissolved in water will sink to the bottom of the water when it is put into water? After stopping the gong, you can still hear the sound of the gong, is the gong surface vibrating right or wrong?

Is it right or wrong that steel travels faster than air? Is it true or wrong that sound cannot travel in water? Sound can only travel in one direction, right or wrong?

Please judge the wrong right or wrong according to the order of the questions, and it is better to write why, I thank you in advance!

Analysis: 1) Water can dissolve some gases, such as carbonic acid solution, and the "dissolution" of water to the solution is called dilution.

2) When rock sugar is dissolved in water, the rock sugar solids will disappear, but it will still exist in molecular form.

3) The lard is dissolved, and it is the lard that is dissolved by heat.

4) Crystals may precipitate and gases may disappear.

5) No, wood will float, and whether it will float depends on its density.

6) Yes, it could also be an aftersound.

7) Yes, iron is denser than air.

8) No, sound propagation requires a medium, which can travel in water.

9) Sound waves travel in all directions in the air.

1.The dish soap rolls quickly, according to inertia: the dish soap is viscous and the bottle with dish soap can be seen as a whole, moving at the same speed. A bottle with water Water and bottle are two parts that move at different speeds, and water acts as a hindrance.

2.The candle does not go out immediately, because the outer surface of the candle does not melt when it comes into contact with water, but it melts closer to the center of the flame and burns.

3.Raw eggs sink to the bottom of the water when placed in a glass filled with water, unchanged.

Raw eggs float when placed in a glass filled with vinegar, and over time, the crust undergoes a chemical reaction, softening and sinking.

1. In the pure ideal case, it should be the same speed, although the mass is not the same, but the acceleration is the same.

2. The candle will not go out, it will form a cylinder because of the edge; The wax is not warm enough to melt, thus preventing the immersion of water, however, the cylinder will not be very high. Because he didn't have enough support.

3. If you put it in water, it will not solidify, but if you put it in vinegar, it will solidify.

It's all lab questions, and doing it yourself is more useful than anything else.

1. Some people who "pretend to be ghosts" have such a "unique skill": they pull out the "ghosts" from the boiling oil pot with their hands, but their hands are unharmed. The secret lies in the "oil" in the pot; The upper layer is real vegetable oil (boiling point is about 300), while the lower layer is other liquids, and the boiling point of this liquid is most likely ——(

Left and right, left and right, left and right2, on a summer night, a unique gathering of "insects" should be held in the forest to study how to adapt more to the increasingly harsh environment. Which of the following animals should not be invited by the organizing committee? ——

a.Mantis. b.Locust.

c.Fly. d.Earthworm.

3. Meteors are a natural phenomenon that we are familiar with, and they can often be seen at night. The following description of meteors, the correct one is——(

a.Meteors can shine on their own, so people can see them.

b.A meteoroid is a celestial body in the Milky Way that orbits the Earth in a certain orbit.

c.Meteoroids that do not burn up fall to the ground and form meteorites.

d.Meteorites are mainly made of rock, so meteorites are also called meteorites.

4. Xiao Ming and his mother went to the supermarket to buy a drink, and found that the logo on the outer packaging of the beverage bottle was like "400ml", which should indicate the drink's - (

a.Volume. b.Quality.

c.**。d.Production time.

5. "Xiaoice Wheat" is a new wheat variety with high yield, disease resistance and high protein cultivated by the School of Life Sciences of Northeast Normal University. It is cultivated by using modern biotechnology to transfer the disease-resistant, high-protein genetic material of wild ice grass to the cells of ordinary wheat. In the cultivation process, it is mainly the operation of the structure inside the cells of wild ice grass - (

a.Cytoplasm.

b.Cell membrane.

c.Nucleus.

d.Cell wall.

6. The following statement is correct——(

a.Shiitake mushrooms belong to prokaryotes.

b.The mesophyll cells in the middle of the leaf belong to meristems.

c.Connective tissue has a variety of functions such as transportation, support, etc.

d.The pancreas does not belong to the digestive system.

A Other than that, other temperatures will hurt your hands.

c Flies can find food in people's homes, they are not very dependent on the environment, and flies are pests and should not be protected.

c Meteors are rocks or pieces of iron flying in the universe, attracted by the gravitational pull of the earth and enter the earth's atmosphere, and burn with air in the atmosphere to emit light, and those that are not burned out become meteorites or meteorites.

A ml means milliliter and is a unit of volume.

c The genetic material is in the nucleus, and the extraction and transfer of genetic material must also be placed in the nucleus to be effective.

b Mushrooms are actually generated by fungi, and fungi are eukaryotes and not prokaryotes; The connective tissue has no transport function; The pancreatic juice mainly secreted by the pancreas contains a variety of digestive juice components such as trypsin and pancreatic lipase, which is an important part of the digestive system. Only b pairs.