The habits of jellyfish?

Jellyfish is a marine coelenterate. Jellyfish body is umbrella-shaped, translucent, white, cyan or yellowish. The diameter of jellyfish umbrella can exceed 45 cm and reach 1 m. Eight thickened (shouldered) wrist bases under the umbrella healed to make the mouth disappear (replaced by the secondary mouth of the suction cup), and there were many rod-shaped and filiform tentacles in the lower mouth and wrist. Its function is to release venom paralysis when it comes into contact with small animals for food. Jellyfish are widely distributed in tropical, subtropical and temperate coastal areas. The common jellyfish in China are edible jellyfish with smooth umbrella surface and only filaments on the mouth and wrist or rod-shaped jellyfish with rods, and Mylabris with many small warts on the umbrella surface.

The life cycle of jellyfish has experienced fertilization, aphid development, larval development, jujube cracking and jujube butterfly formation. In addition to the sexual reproduction of sperm and eggs in vivo, the salamander larvae of jellyfish will also produce creeping roots to form foot sacs, and even split into multiple disks, which will greatly increase their individual number through asexual reproduction.

In coastal waters, this gentle and elegant animal often attracts people's great love and interest. However, don't indulge in hugging such animals in the sea, the consequences and prospects are mostly bad. The stinging sac of fresh jellyfish contains venom, which is composed of a variety of substances rich in skin. People who catch jellyfish or swim at sea will be injured when they touch the tentacles of jellyfish, causing redness, swelling, heat and pain, epidermal necrosis, chills, irritability, chest tightness, unbearable wound pain and other symptoms. Severe cases may be life-threatening due to dyspnea and shock. In midsummer, it is the peak season for jellyfish to grow, and it is also the peak season for fishermen to fish at the seaside or tourists to be easily stung when swimming at the seaside. Jellyfish are distributed in the coastal waters of China, and there are many kinds, and the nature and harm of the toxins secreted by them are not the same. However, due to the difference of individual sensitivity, jellyfish stings only have general allergic reactions, which can lead to death seriously. We must pay attention to effective prevention and active rescue treatment.

Jellyfish venom can cause different degrees of harm to human body. For example, sea wasp jellyfish can secrete venom similar to cobra, which is the most harmful to human beings and can kill people within 5 minutes after being stung. After the jellyfish stung the human body, it took many days for the patient to get rid of the pain. There are common jellyfish floating in the Yellow Sea off the coast of China, which can secrete peptide poison. Macular jellyfish are mainly distributed in the coastal areas of Guangdong and Guangxi, and have certain toxicity. Real jellyfish exist in the Yellow Sea, the East China Sea and the Bohai Sea. Is it poisonous? 4 send? What's the matter with you? ? U, the more you detain, the more you wash?

China has a vast sea area, and a considerable number of jellyfish stings occur from July to September every year. In the past, fishermen mainly caught jellyfish, and recently some patients were stung while swimming at the seaside. For example, in recent years, more than 3,400 people have been stung by Qinhuangdao seaside. According to the statistics of Beidaihe Seaside Hospital, a tourist resort, during the five years from 65438 to 0989, 3030 cases of * * * were treated, of which 0.3% were fulminant allergic pulmonary edema and 4 cases died (all severe shock).

Jellyfish toxins are stored and distributed in gill boxes. The 65,438+0g card box contains 55 million single-needle card boxes. Generally, after fishing, its toxicity can disappear quickly after processing. Animal experiments have proved that jellyfish toxin is harmful to the heart transmission system of mammals and the heart of crustaceans, and can cause contraction of small intestinal smooth muscle in rats. It is found that jellyfish toxin is tetramine complex, 5- hydroxytryptamine and polypeptide, which has strong histamine reaction. Its effects of dilating blood vessels and enhancing capillary permeability are 10 and 15 times that of 5- hydroxytryptamine respectively. It can also cause smooth muscle contraction or allergic reaction, leading to severe pulmonary edema and anaphylactic shock. After being stung by jellyfish, people have different symptoms due to different toxicity, toxins and individual sensitivity.

The thin and tender parts of human skin are most likely to be stung. It usually takes a few minutes to get an electric shock-like tingling. After a few hours, linear electric tingling will gradually appear in the injured area. After a few hours, the injured part will gradually appear linear blood rash with erythema, itchy and burning. Lighter ones can heal themselves in about 20 days. Patients with strong sensitivity may have erythema, edema, wheal, blisters, ecchymosis and even epidermal necrosis. The general manifestations of patients may include fidgeting, chills, abdominal pain, diarrhea, listlessness, chest tightness and shortness of breath. In severe cases, cough, asthma, vomiting of white or pink foam sputum, accompanied by signs of anaphylactic shock such as weak pulse, cyanosis of skin and decreased blood pressure. If the rescue is not timely, this stinger can die in a short time.

The most important thing to prevent jellyfish stings is to avoid contact with jellyfish, especially fishermen who work should do personal protection and not be careless. When fishing, use tools as much as possible, do not directly contact jellyfish whiskers, and prohibit people with specific sensitive physique from going to sea to work. During the jellyfish flood season, buoy fences should be set up in seaside tourist destinations, and eye-catching publicity and warning signs should be set up at the seaside to cooperate with the publicity and broadcasting of popular science education to prevent injuries and improve tourists' knowledge and ability of self-protection. People who swim or take a boat in the sea should never touch jellyfish, let alone catch them, because once an accident happens at sea, it is more difficult to rescue them. Once bitten by a jellyfish, the injured must not panic. As long as you go to the hospital for treatment in time, you will generally get better and recover quickly. On the other hand, if the stung person acts improperly or negligently, it is easy to drown and fall, or it will be dangerous and aggravate the condition due to the delay of treatment.

Jellyfish are extremely nutritious. According to the determination, every100g of jellyfish contains protein12.3g, carbohydrate 4g, calcium182mg, iodine132mg and various vitamins. Jellyfish is also a good medicine for treating diseases. Chinese medicine believes that jellyfish has the functions of clearing away heat and toxic materials, resolving phlegm and softening hardness, lowering blood pressure and reducing swelling. "Return to Yan Lu" said: "Sea snake is also a panacea, which can dispel qi and eliminate phlegm, diminish inflammation and eat it without hurting healthy qi. Therefore, asthma, chest pain, abdominal pain, fullness, constipation, leukorrhagia, malnutrition, jaundice and other symptoms can be eaten. " . The processed products are called jellyfish skin in the umbrella and jellyfish head in the wrist, and the commodity value of jellyfish skin is more expensive than jellyfish head.

As early as the Ming Dynasty, fishermen knew that fresh jellyfish were poisonous, so they had to pickle them with salt and alum, soak them to detoxify them, and filter out the water before they could be eaten. However, from ancient times to the present, it is not uncommon for fishermen in the seaside of South Guangdong to eat fresh jellyfish poisoning by accident because they are greedy for delicious seafood. In addition, jellyfish, like other seafood, are easily contaminated by halophilic bacteria, and eating cold jellyfish silk by mistake can cause bacterial food poisoning. A bacterial food poisoning accident occurred in a hotel in Jiangmen City, Guangdong Province, where 73 people ate cold jellyfish.

Summer is the season when intestinal diseases are easy to occur and become popular. As a warning, jellyfish silk should be handled carefully when eaten raw, and attention should be paid to hygiene during operation to prevent flies, dust and pollution. Jellyfish had better be shredded, then washed repeatedly with cold boiled water and dried to prevent food poisoning.

In China, jellyfish fishery has a long history, with a maximum annual output of 58,000 tons. However, due to reasons that are not fully understood so far, its resources change greatly every year, sometimes lying on the beach before processing, and sometimes nowhere to be found.

The State Council stipulates that the jellyfish fishing season will start at August 10 every year. However, in recent years, driven by economic interests, fishermen in Liaodong coastal areas only pay attention to immediate interests, stealing ahead of time, and destroying the growth of jellyfish seedlings is becoming more and more serious. Especially in recent three or four years, a large-scale fishing frenzy has been formed. In late July, jellyfish were caught before they grew up. Every fishing season, faced with thousands of illegal fishing boats, a limited number of fishery inspection boats and inspectors are really unable to do so. Some lawless elements are arrogant and often use violence against inspectors on fishery vessels. This lawless situation is becoming more and more serious now.

jellyfish

Jellyfish is a very beautiful aquatic animal. Although it has no spine, its body is very huge, and its huge body is mainly supported by the buoyancy of water.

Jellyfish is shaped like a transparent umbrella with different diameters. The umbrella of the big jellyfish can reach 2 meters in diameter. There are some whisker-like strips on the edge of the umbrella, which are called tentacles. Some tentacles can be as long as 20 to 30 meters, which is equivalent to the length of a big whale. Jellyfish floating in the water extend long tentacles around them, and some jellyfish also have umbrellas with various patterns. In the blue ocean, these swimming jellyfish of different colors are very beautiful.

Jellyfish appeared before dinosaurs, dating back to 650 million years ago. At present, there are about 200 species of jellyfish found in the world, and there are about 8 common species in China, namely Haiyue jellyfish, Baixia jellyfish, jellyfish, jellyfish and so on.

The tentacles of jellyfish are covered with stinging cells, like small beans stuck to the tentacles. This kind of stinging cell can shoot poisonous silk, and when it meets an "enemy" or prey, it will shoot poisonous silk to scare off or poison the "enemy". There is a small ball on the thin handle in the middle of the jellyfish tentacles, and there is a small "listening stone" in it, which is the "ear" of the jellyfish. Scientists simulated the sound wave transmission organs of jellyfish and found that the information of ocean storm 15 hours before its arrival could be detected.

Although jellyfish is very beautiful and comfortable in water, it can hardly live without water. The water content of jellyfish reaches 98%, and its eating, digestion and excretion must be completed in water. Without water, jellyfish's body will become smaller and uglier.

Jellyfish is more dangerous than cobra. A few years ago, the American World Wildlife magazine listed 10 species of the most poisonous animals in the world, and the box jellyfish living in the ocean topped the list. Box jellyfish, also known as sea wasps, belong to coelenterates and mainly live in the coastal waters of northeast Australia. An adult box jellyfish the size of a football is mushroom-shaped and almost transparent. An adult box jellyfish has billions of poison sacs and needles on its tentacles, enough to kill 20 people. The toxicity is obvious. Its venom mainly damages the heart. When the venom of box jellyfish invades the human heart, it will destroy the consistency of the beating rhythm of human cells, thus making the heart unable to supply blood normally and leading to rapid death.

The largest jellyfish is the arctic jellyfish distributed in the northwest Atlantic. 1870, an arctic jellyfish was washed into Massachusetts bay, USA. Its umbrella is 2.28 meters in diameter and its antenna is 36.5 meters long. The smallest jellyfish is only 12 mm long.

When the comb jellyfish swims in the sea, it will emit blue light, and when it emits light, it will become a dazzling colored ball; When it swims, the light band swings with the waves, which is very beautiful. At present, biologists in Singapore are conducting an experiment to transplant the luminescent genes of jellyfish to other fish.

Powerful and deadly jellyfish also have natural enemies. There is a kind of turtle that can freely shuttle through jellyfish, and its tentacles can be easily broken with its mouth, so that they can only roll up and down, and finally lose their resistance and become a "good meal" for turtles.

Online forums also call female irrigation fanatics "jellyfish"

Jellyfish is a kind of lower coelenterate, belonging to coelenterate and Cephalopoda in taxonomy. There are many kinds of jellyfish, about 250 species in the world, with diameters ranging from 10 cm to 100 cm, which are common in the oceans all over the world. People often classify them according to different umbrellas: some umbrellas emit silver light and are called silver jellyfish; Some umbrellas are like a monk's hat, called a monk's hat jellyfish; Some umbrellas are like white sails on a ship, called sail jellyfish; Some are like umbrellas, called umbrella jellyfish; Some umbrella-shaped bodies shine with rosy clouds, which are called chardonnay jellyfish ... most of them can only live for a few weeks, and some live for about a year. Some deep-sea jellyfish can live longer. The umbrella of ordinary jellyfish is not very big, only 20 ~ 30 cm long, but the giant umbrella of the larger summer jellyfish can reach 2 meters in diameter and the drooping tentacles can reach 20 ~ 30 meters. 1865, a jellyfish was washed ashore on the coast of Massachusetts, USA. Its umbrella is 2.28 meters in diameter and its antenna is 36 meters long. Pull the tentacles of this jellyfish apart. It is 74 meters long from the tip of one tentacle to the tip of the other. Therefore, it can be said that jellyfish is the longest animal in the world.

The main component of jellyfish body is water, which is composed of endoderm. There is a thick interlayer between the two layers, which is not only transparent, but also floating. When they are moving, they use the reflection of water in their bodies to move forward. Seen from a distance, they float fast in the water like a round umbrella. When jellyfish appear in groups at sea, they live closely together and float in the depths of the sea as a whole, which is very spectacular. The waves are like snow, and the blue sea is dotted with many beautiful umbrellas, flashing light green or blue-purple light, and some have rainbow-like halos. Many jellyfish glow. The slender tentacles spread out around and floated with them. The color and swimming posture are beautiful. There is a special gland in the umbrella of jellyfish, which can release carbon monoxide and expand the umbrella. When a jellyfish encounters an enemy or a big storm, it will automatically release gas and sink to the bottom of the sea. After the sea is calm, it only takes a few minutes to generate gas to make itself swell and float. When the ctenophore swims in the sea, the eight meridian tubes can emit blue light, and when it emits light, the ctenophore becomes a dazzling colored ball; There are several parallel bands of light around and in the middle of jellyfish. When it swims, the light band swings with the waves, which is very beautiful. Jellyfish glow through a wonderful protein called Aquimine. When this protein is mixed with calcium ions, it will emit strong blue light. The more amount of esquimine in jellyfish, the stronger the light it emits. Each jellyfish contains only 50 micrograms of this substance on average.

Although jellyfish are beautiful and docile, they are actually fierce. Under the umbrella, those slender tentacles are its digestive organs and weapons. The tentacles are covered with stinging cells, which can shoot venom like poisonous silk. After being stung, the prey will soon be paralyzed and die. The tentacles will hold these prey tightly, retract them and suck them with corals under the umbrella. Every coral can secrete enzymes to rapidly decompose protein in its prey. Because jellyfish have no respiratory organs and circulatory system, only primitive digestive organs, so the captured food is immediately digested and absorbed in the lumen. On a hot summer day, when we are swimming in the seaside tide, sometimes we suddenly feel a stabbing pain in our chest, back or limbs, as if we had been whipped. The jellyfish must be stabbing people again. But generally, after being stung, the broken jellyfish will only feel burning pain and appear red and swollen. As long as it is coated with nitroglycerin or vinegar, it will reduce swelling and relieve pain in a few days. But in the waters from Malaysia to Australia, there are two species called sea bee jellyfish and hand-dragging jellyfish, and their secretions are very toxic. If stung by them, they will die of breathing difficulties within a few minutes, so they are also called killer jellyfish. Therefore, when you are stabbed by jellyfish and have difficulty breathing, you should immediately give artificial respiration or inject cardiotonic, and you must not be careless to avoid accidents. Once a jellyfish meets its prey, it will never let it go easily. But like rhinoceroses and birds that clean up parasites, jellyfish have their own companions. It is a small herding fish, only 7 cm long. It can swim freely between the tentacles of jellyfish, but it is not afraid at all. When a big fish comes, the little sheepdog will swim to the middle of the tentacles under the giant umbrella as a safe "refuge" and use the device of jellyfish stinging cells to cleverly avoid the enemy's attack. Sometimes, small shepherds can even lure big fish into the hunting range of jellyfish to kill them and let them eat the leftovers left by jellyfish. So why don't the stinging cells on the tentacles of jellyfish hurt the sheepdog? This is because the little sheepdog is flexible, can skillfully avoid poisonous silk, and is not easy to get hurt, but it is only accidental and accidental to die under poisonous silk. Jellyfish and small herding fish were born together and used each other. Jellyfish "protected" the small shepherd fish, and the small shepherd fish swallowed the small creatures that lived in the jellyfish.

Powerful and deadly jellyfish also have natural enemies. There is a kind of turtle that can freely shuttle through jellyfish, easily break their touch with their mouths, so that it can only roll up and down, and finally lose its resistance and become a "good meal" for turtles.

There is a small ball on the thin handle in the middle of the jellyfish tentacles, and there is a small auditory stone inside, which is the "ear" of the jellyfish. Infrasound waves generated by the friction between waves and air hit the auditory stone, stimulating the surrounding nerve receptors, so that jellyfish can get information more than ten hours before the storm warning, so they seem to have been ordered to disappear from the sea at once. Scientists tried to simulate the sound transmission organs of jellyfish and found that they could detect the information of ocean storms 15 hours ago.

Jellyfish is a kind of lower coelenterate, but its lineage is enviable. Jellyfish give birth to small jellyfish. Although the small jellyfish can live independently, it seems that there is a deep affection between parents and children, so the small jellyfish is attached to the jellyfish. Soon after, the little jellyfish gave birth to their grandchildren's jellyfish, and they are closely related to each other.