Fish breathe with their gills, so what else does its nostrils do?

It is true that the breath of a fish has nothing to do with its nose, but the nose of a fish is a fishFunctional organs that do not have to be missing, which plays a very important role.

As with terrestrial animals,The nose of a fish has an olfactory effectIn flowing water, the fish do not need to swim, the water flows through the nose of the fish, and they can smell the smell of distant places, and in still water, the fish need to swim fast to perceive the information outside.

The fish's olfactory receptors seem to beA clump of folded epithelial cellsUnlike terrestrial animals, fish have nostrilsDoes not produce mucus, which does not produce nasal discharge; The nerves in the nostrils of the fish will leadThe olfactory center of the brain, after the olfactory center receives the signal, the fish will react in a variety of ways.

The olfactory system of fish plays an important role in the following behaviors:

Fishing enthusiasts tend to make nests when fishing, theseThe smell of the bait is relatively strongFish from far away will be able to pass through their noses in a very short timePerceive the location of the bait

Sharks, for example, have a very sensitive sense of smell and are said to be sharksIt can smell the smell of blood at the concentration of one part per millionto be able to perceiveThe location of schools of fish a few kilometers away, so that they can hunt accurately.

Fish can smell through their nosesSmell of the same kindThis smell can be called pheromones, especially the smell of the opposite sex, which is more sensitive during the spawning period of the fish.

CompanionsWhen you encounter a predator, it also emits a pheromone, and when other members of the same kind smell this information, they will start running away from a long distance.

There are a lot of fishMigratory and migratory habitsSome fish are thousands of kilometers away and are able to accurately return to their place of birth, largely relying on their noses.

For example, salmon will live in the ocean since they are born, often thousands of kilometers away from their birthplace, but when spawning, salmon will return to their birthplace after a lot of hardships, although in the ocean it relies on sensing the earth's magnetic field to guide it, butBack in the freshwater stream, it's the nose that guides the way.

And a lot more. The nostrils are used to distinguish odors, play a certain role in smell, so that they can perceive signals from the outside world, can also forage for food, can communicate with their own kind, and can guide directions.

The nostrils can assist in breathing, and at the same time can expel debris from the body, excrete toxins, forage for food, and filter oxygen, which is very helpful for fish.

It has the function of finding prey, and the nostrils have a sense of smell, so that the fish can better survive and catch food.

The gills are the respiratory organs of the fish, which are composed of gill filaments, gill rakers, and gill arches, and the main part is the gill filaments, which are densely covered with capillary ladan, so the gills are bright red. When the water flows through the mouth, the oxygen dissolved in the water seeps into the capillaries in the gills; The carbon dioxide in the blood, on the other hand, exudes out of the capillaries and is excreted from the body through the parotid hole at the posterior edge of the gill cover.

Fish breathe through their gills, which have many capillaries, and the walls of the capillaries are so thin that gases can easily penetrate into them. When fish absorb water, oxygen enters their mouths along with the water, and when the water passes through the gills, the oxygen in the water seeps into the capillaries of the gills. The carbon dioxide produced by the fish is also discharged from the gills into the water.

In this way, the gills of the fish play a role in breathing.

The answer on the 1st floor is not comprehensive enough, and the principle of artificial respiration should be traced back to the intrapulmonary pressure.

Cycle of intrapulmonary pressure ** Substitution is the direct driving force that causes lung ventilation, according to this principle, when natural breathing stops, the pressure difference between intrapulmonary pressure and atmospheric pressure can be artificially established to maintain lung ventilation.

This is called artificial respiration.

Artificial respiration is divided into two types: positive pressure and negative pressure.

Positive pressure artificial respiration mainly refers to mouth-to-mouth artificial respiration, and negative pressure refers to rhythmic squeezing of the chest, which will be ventilated in order to maintain changes in intrapulmonary pressure.

When a person exhales and exhales, the volume in the lungs becomes smaller and the pressure increases, and when he inhales, the volume in the lungs becomes larger and the pressure decreases.

** (mudskipper), intestinal tube (loach) and balloon (lungfish).

Yes. The lungs of flesh-finned fish are well developed and may be used regularly. So amphibians are practically not a problem to breathe in the air, but they continue to use the lungs they inherited from their ancestors of flesh-finned fishes.

The main difference between fishes and amphibians in this respect is that most fish with lungs breathe by gills and are still the primary mode of respiration, while the lungs are usually only an auxiliary respiratory organ, but the earliest terrestrial vertebrates basically breathed air with their lungs and only with gills during their youth or larval stage.

Barramundi does not use gills and breathes with lungs.

Breathe with gills, jellyfish. Not fish.

Thoracic and abdominal breathing method refers to the contraction of the diaphragm by the contraction of the diaphragm, the alveoli stretch downward and squeeze the abdominal cavity, the abdominal muscles relax forward and downward and expand naturally, and the psoas muscles and intercostal muscles naturally expand outward to achieve the purpose of expanding the chest cavity for breathing.

Combined thoracoabdominal breathing:

Inhale quickly and exhale slowly, with your chest up and your shoulders broad. The abdomen is slightly bulging during inhalation, and the chest cavity is consciously wide;

Exhale with your abdomen relaxed but not forcefully contracted, and keep your ribcage wide.

Focus on the diaphragm and feel the breath on the diaphragm as you exhale.

Breathing exercises rely on contraction and relaxation of the intercostal and diaphragmatic muscles.

When the intercostal muscles contract in the lug cavity and diaphragm, the thoracic volume increases, the lungs expand, and the air pressure in the lungs is lower than the outside atmospheric pressure, and the inhalation is completed. When the intercostal muscles and diaphragm are relaxed, the thoracic volume decreases, the lungs retract, and the air pressure in the lungs is higher than the outside atmospheric pressure, and the exhalation is completed.

The watchtower is incorrect.

Abdominal breathing refers to a breathing method in which the diaphragm of the human body rises and falls to increase the volume of the chest cavity and reduce the pressure, so that air can enter the lungs.

Thoracic breathing refers to the method by which the body changes the volume and pressure of the chest cavity through the contraction and relaxation of the rib muscles, allowing air to be inhaled.

The average person's breathing is a mixture of breathing, which means that there are both movements.

It's gills, but the gills are not the same.

The principle of fish breathing with gills: the gills are the respiratory organs of bony fish, and the water flows out through the gills after entering the mouth, and the direction of the water flow is exactly the opposite direction of the blood flow in the gill plate, forming a countercurrent exchange system that can efficiently bring oxygen and take away carbon dioxide, so that the oxygen in the water seeps into the capillaries of the fish gills, and the carbon dioxide produced in the fish body is also discharged from the gills into the water.

The gills of fish have two large gill covers, and the cavity inside the gill cover is called the gill cavity. Lifting the gill cover, you can see that there are four gills on each side of the throat, and each gill is divided into two rows of gill pieces, each row of gill pieces is composed of many gill filaments arranged in an arrangement, and many small gill filaments are born on both sides of each gill filament.

1. Zhengzhi fish is an aquatic animal, and its gills are the respiratory organs of most aquatic animals, and its position, shape, and structure are very different;

2. Gill is divided into two categories: inner gills and outer gills. Most of the gills of fish are internal gills, referred to as gills, which are born on both sides of the head, protected by gill covers, and communicate with the outside world with gill holes;

3. The gill is composed of gill pieces, which is the place where the fish carries out the gas exchange, the gill pieces are arranged with comb-like gill filaments, and the gill filaments are densely covered with capillaries, when the water passes through the gill filaments, the capillaries take up the dissolved oxygen in the water, and at the same time discharge the carbon from the dioxygen wheel into the water;

4. The outer gills are the respiratory organs of the fish, which are exposed on both sides of the back of the head, without covering, and are filamentous or pinnae-like.

Fish have four gills. It has two gill covers, and when you lift them, you can see the gills inside, which are its respiratory organs. When the water enters through the mouth, it flows out of the gills, and because the direction of the water flow is opposite to the flow of blood in the gill filaments, it can efficiently absorb oxygen from the water and excrete carbon dioxide at the same time.

Fish have four gills. It has two gill covers, and when you lift them, you can see the gills inside, which are its respiratory organs. When the water enters through the mouth, it flows out of the gills, and because the direction of the water flow is opposite to the flow of blood in the gill filaments, it can efficiently absorb oxygen from the water and excrete carbon dioxide at the same time.

1. Fish maw: For bony fish, the swim bladder is an important organ that changes the density of the body, which allows it to float or dive in the water. But for some of the more special fish, such as the African lungfish, the swim bladder is an auxiliary respiratory organ.

When the river enters the dry season, the fish will be exposed to the air, and this is when it needs to breathe with a terminal swim bladder.

2. **: Mudskipper is a fish that can survive after being out of water, relying on the breathing ability of **. The fish usually lives in shallow waters along the coast and stays on the tidal flats after low tide, where it can forage for food, and can even jump and move with the help of pectoral stems.

3. Intestines: The loach that lives in the mud is also a fish, and it can also go to the surface of the water to swallow air when the water body is short of oxygen, because its intestines can breathe. In addition, after the pool dries up, it can burrow into the wet mud, and as long as the surface of the body is kept moist, it will not die.

Among the spinal propulsions, only fishes and rotatoida are aquatic animals that breathe with gills throughout their lives, but the gills of fishes are formed by ectoderm, and the gills of round-mouthed species originate from the endoderm. Fishes generally have 5 pairs of gill arches (a few have 6 or 7 pairs) with 5 branchial slits on each side of the pharynx. The gills are mainly composed of several parts, such as the gill arch, the gill septum, and the gill lobes.

The gill arch plays a supporting role, its inner edge is a gill raker, the blood vessels in and out of the gill are passed through the gill arch, the outer edge of the gill arch is the gill septum, the front and back protrusions of the gill septum form the gill meridian, the countless gill meridians are closely arranged into ctenoid gill lobes, and the countless small protrusions on the gill filaments are called gill lobules, which are the places of gas exchange. The gill lobules are covered with capillaries, and the blood finally flows into the sinusoidal space, the wall of the sinus-like space is composed of connective tissue that plays a supporting role, and the surface layer of the gill lobules is a single layer of epithelial cells, so the gills are bright red. The gills of bony fishes are more primitive, the gill slit is open in the body, the gill septum is developed, and there is one and a half gill before and after, these two half gill are collectively called the whole gill, and the outer side is protected by the gill cover, and the inner side below the gill cover is the gill cavity or gill chamber, and the total gill hole is opened backward outside the body.

The posterior edge of the operculum extends with a soft operculum membrane that seals the operculum tightly. Cartilaginous fishes have 4 full gills and 1 half gill for a total of nine pairs of half gills without gill covers.

In addition to respiration with gills, fish also have organs that assist respiration, such as loaches, which use intestinal swallowing gas for intestinal respiration; mudskippers, catfish, etc. can breathe; Yellow eels, etc., can use the mouth to breathe; Mullets, bearded catfish, etc. can perform folded gill breathing; Barramundi and the like breathe with a swim bladder. Fishes have two nostrils, but not the mouth (except for the two subclasses of lungfish and total fins).

The swim bladder is a membranous bundle located on the back of the body cavity between the digestive tract and the kidneys, and its shape varies depending on the type of fish, with one, two, or multiple chambers. The main function of the swim bladder is to regulate the sinking and floating of the fish body or stay in a certain water layer, when the volume of the swim bladder expands and increases, the specific gravity of the fish body in the water becomes smaller, and the fish floats, when it wants to stay in a certain water layer, the swim bladder needs to release part of the gas. When the size of the swim bladder decreases, the specific gravity of the fish body in the water increases, and the fish sinks.

When you need to stay in a certain water layer from shallow to deep, you need to inhale a part of the gas. In conclusion, the increase or decrease of gas in the gills is related to the pressure in the water. The change of swim bladder volume is a relatively slow process, so swim-bladder fish should only live in a relatively fixed water layer.

Living in the deep sea, in rapids, or in benthic habitats, or in fast swimmers, the swim bladder has lost its role in their lives. For example, sharks, mackerel, tuna, etc., which swim very fast, do not have swim bladders. Therefore, they must always be in motion and can only be underwater.

Another kinetic energy of the swim bladder is gas exchange, cartilaginous fish and a few bony fish use the swim bladder to assist in breathing, such as the multi-finned fish in Africa, in the dry season, use 1 pair of lung-like swim bladders for gas exchange. Barramundi, gars, etc., can also breathe with their swim bladders.

In-depth understanding of the breathing principle of fish gills, the fish of nature is really a magical existenceIn-depth understanding of the breathing principle of the gills, the fish of nature is really a magical existenceIn-depth understanding of the breathing principle of the gills, the fish of nature is really a magical existence.