Why can t fish live without water?

Physics: There's water pressure in the water, and this water pressure is just right for the fish and for survival, and if the fish lives in the air for a long time (I say if), then its heart won't be able to stand it.

Chemistry: The gills can be washed away from the water"Dust"Not in the air. The gills of fish must be watered in order to function.

Biology: The main food of fish is plankton, and plankton happens to live in the water, which may be adaptation!

Philosophy: Everything has its inevitability and relativity.

Mathematics: This explanation is not very clear, I think there are too many fish, I don't know what mathematical units to calculate, and there is a lot of water on the earth, so they live in the water.

History: The beginning of the earth began in the water, which is the beginning of all life on the earth.

Theology: God's favor gives the fish free space, and God is making fish to arrange a living environment for it to be in the water

I don't know if it's reasonable.

Because just like us humans can't survive without air, water is the same for fish, and fish can't survive without water.

I'm stupid, I don't know anything.

Personal feelings. Physically, fish cannot survive without water. Because it always lives in water. Water has the nutrients it needs.

Chemically, fish may need H2O more.

Creatures, fish can't live on land without feet, and since they can't walk, they don't have food. Mortal.

Philosophy, if this world fish can live on land too. It's time for humans to settle on Mars.

Math, this fish is not a higher animal. No matter how you count it, you can't add it with people.

History, the history books say that fish never went to land.

Theology, the fish can only jump into the dragon gate when they are in the water.

Fish breathe with gills and can only absorb oxygen dissolved in water, so they must live in water (biological, physical) water and air in a different proportion of oxygen (mathematics, chemistry).

This is a false conclusion, the fish can live without water, but it cannot be stored for a long time (philosophy) God said, it should exist where the fish should be, and all things in heaven and earth have their own duties! (Theology).

I can only explain it this way:

From a biological point of view, this is due to the fact that the gills of the fish are so tight that if they are taken out of the water, the gills will be stacked on top of each other and will not be able to absorb oxygen from the air. But in the water, the gills float through the water and absorb oxygen.

It's useless to say anything else :

Biological perspective: Leaving the water, the gill filaments of the fish are adherent, the gill filaments cannot carry out gas exchange, the capillaries on the gill filaments cannot get oxygen, and the fish dies of lack of oxygen!

Let's analyze it from a biological point of view.

This is because the fish relies on the four gills in the gill cavity to suck the oxygen in the water in, and then discharges the carbon dioxide in the body into the water through the gill cover. As a result, the fish can no longer breathe with its gills, and without breathing, the fish dies of lack of oxygen.

Fish that can live out of the water.

1. Mudskipper: Mudskippers live in swamps and estuaries and mudflats, and are known for their ability to climb and bounce outside the water, breathe air and moisture in the gill cavity outside the water, and can survive on land for a long time, and will die if they do not swim out of the water regularly.

Muddlefish have the habit of foraging out of water, and often rely on the pectoral fin muscle stalk to crawl and jump on the mud to forage for food at low tide, or climb on rocks and mangroves to hunt insects, or climb on rocks to bask in the sun. When it comes out of the water, its well-developed gill chambers are filled with air, and its tail is immersed in water as a breathing aid, and living away from water has become an important habit.

2. Climbing perch: Climbing perch is commonly known as walking fish, known for being able to live, crawl and climb outside the water, breathe air, live in ponds and ditches, and sometimes jump sharply with the help of hard spines on the lower edge of the tail and gill cover, and can briefly leave the water or "walk", so it is commonly known as walking fish.

The perch is so well developed that it breathes air, supports its body with its pectoral fins, and its tail fin swings from side to side, moving forward like a seal, and can maintain its life on land for hours, because some of the gills are folded like rose petals, and they are densely covered with capillaries that directly absorb oxygen from the air and drain carbon dioxide from the blood.

This fish that can survive in the dirt is the African lungfish, and when the pond dries up, the lungfish burrow into the dirt and secrete mucus to form shells that wrap themselves up because their lungs can breathe air. It is known that there are fewer and fewer areas for lungfish to breed and inhabit, and they are currently in danger of extinction.

Barramundi

I believe that many people will have such doubts, in the arid and hot land of Africa, how this fish survives, Huang Chengming gave the answer: this fish wraps itself up and enters a dormant state, because it does not eat or drink, so the metabolic rate is very low, African lungfish is in this way to spend a special unfavorable environment, until the new rainy season comes, they wake up from the bag.

It is said that this fish is found not only in Africa, but also in Australia. In contrast to ordinary fish, it uses its gills to breathe with its lungs, its gills when it is watery, and its lungs when it is empty. African fish also have close relatives – the American lungfish and the Australian barramundi.

Like the African and Australian lungfish, most of the bones are cartilage for life, but they retain a well-developed notochord with a thick sheath, and the lungs are spiral valves, which are very similar to cartilaginous fishes.

Barramundi has been a protected animal for the past 100 years, and was declared endangered in 2002, meaning that there may be fewer and fewer barramundi on the planet.

Fish are aquatic animals that need an aqueous environment to survive.

Without water, fish cannot survive.

So, how long can a fish live without water in a big acacia beard?

First of all, the activity of fish needs the support of water.

Water temperature, dissolved oxygen content, pH value, etc., are all key factors for fish survival.

If the temperature of the water is too high or too low, the fish will be damaged or even die.

In addition, the amount of dissolved oxygen in the water is also an important factor in the survival of the fish, if the dissolved oxygen content is too low, the fish will lack oxygen, which will eventually lead to death.

Secondly, the digestive system of fish also needs the support of water.

The digestive system of fish needs water to lubricate and roll in order to digest food.

If there is no water, the digestive system of the fish is damaged, which affects the survival of the fish.

Finally, the excretory system of fish also needs the support of water.

The excretory system of fish needs water to be cleaned in order to expel waste from the body.

If there is no water, the excretory system of the fish is damaged, which affects the survival of the fish. Talk about it.

In conclusion, fish cannot survive without water.

In general, fish can live without water for a few minutes, and no more than a few hours at most.

Therefore, in order to protect the survival of fish, we should strive to protect the water environment and reduce pollution so that fish can have a better living environment.

Fish mainly breathe through the gills, and the flow of water flows in from the mouth and out of the gill holes, and the gas exchange is carried out as it passes through the gills.

Therefore, the gills have a special structure. Fish generally have 5 pairs of gill arches, the inner edge is the gill raker, the outer side of the two more than the gill piece, the gill is composed of countless gill filaments arrangement, each gill filament and many protruding gill pieces, the gill filaments are composed of 2 cells, with abundant microvessels, is the place of gas exchange.

The adjacent gills are staggered and the water is convected in them, guaranteeing maximum gas exchange between the blood and the water. When the fish leaves the water, the gill filaments and gill pieces are adhered to each other, the breathing area is greatly reduced, and sufficient oxygen can not be supplemented, and the gill filaments are exposed to the air, and the gill filaments are dried out due to water evaporation, which destroys the structure of the gills and makes them lose their respiratory function and die.

Although there are fish **, air sacs, and intestinal tubes that can assist breathing, those are far from enough. So the fish must have water to live.

The fish caught in the river cannot be raised because of the lack of oxygen, so it is necessary to add oxygen to the fish in time, otherwise it is easy to die. If it is raised directly in tap water, it will also cause the death of the fish, so you can dry the tap water and raise it again or use the water in the river directly. Because the fish in the river are timid and refuse to eat when caught, they can easily die.

If you want to feed, you need to keep oxygenating the fish, and keep the water flowing, otherwise it is easy to turn your stomach if you can't feed it.

It is best to raise fish in the river with water in the river, and fish will die if you raise them in tap water, because there is no oxygen in the tap water, and there are no nutrients that are beneficial to the fish, so it is best to dry the water or use the water in the river directly.

The fish in the river are also small, they will refuse to eat after being caught, and it is not easy to feed for a long time, and there is no problem with raising the aeration pump for a short period of time, and they can also feed a small amount for a period of time.