The most beautiful and bright jellyfish. Interesting facts about jellyfish

Jellyfish appeared quite a long time ago. Thanks to their formless appearance these animals were called jellyfish. The name draws an analogy with Medusa the Gorgon, the Greek mythical goddess. They were tied by the tentacles that the Gorgon had on her head in the form of snake hair, which, like jellyfish, was poisonous.

Where do they live?

Jellyfish are found all over the world and are found in salty seas. Jellyfish differ according to their place of residence. Each body of water in the World Ocean contains a separate species that does not spread beyond its borders. There is only one species of jellyfish in the entire world, which can be found in every freshwater body.

Also in one sea or ocean there can be such different jellyfish as:

• cold-water (warm-water);
• deep-sea (shallow-water, or those that adhere to the surface).

However, even those that are at the top of the reservoir at night sink to the bottom during the day, this is due to the search for food. Everything is clear with vertical movement, but let’s talk about horizontal movements in more detail. When swimming, they actively push water out from under their umbrella, thanks to the contraction of muscle fibers that are located along the edge of the jellyfish’s dome.

But still, the speed of movement is small and it accelerates only because of the current. In a relaxed state, it sinks to the bottom. Jellyfish are such primitive animals that they do not even interact with each other, that is, they are solitary in life.

Nutrition

Jellyfish are predators. They grab the victim and eat it. They feed on small sea creatures - fish eggs, small fish, and fish, smaller jellyfish, zooplankton. The size of the food depends on the size of the jellyfish itself, i.e. something she can swallow whole.

Appearance of a jellyfish

All jellyfish have a primitive structure, so they are internally similar and have a uniform physiology. Jellyfish can be distinguished by their radial symmetry of their organs. Also hallmark It can also be said that the number of organs is always a multiple of four (8 blades on an umbrella).

The jellyfish spends all its time in water, and it itself is 95% water. A jellyfish has no bones and therefore, as soon as it hits land, it immediately loses the ability to move and instantly dries up. The consistency of the jellyfish is similar to jelly, which is what makes it attractive.

The body size of a jellyfish varies from 2mm to 2.2 meters in diameter. She has no eyes, but she has special organs located along the edge of the umbrella. They determine the location (bottom or top) and react to lighting. With their help, jellyfish know when it is day and when it is night.

In water, jellyfish are almost invisible, they are transparent. This is excellent camouflage and protection. On the tentacles and other parts of the body there are stinging cells that secrete poison. This poison can cause death or severe burns. Almost all jellyfish living in cold seas white. Tropical jellyfish warm waters brightly colored.

The structure of jellyfish tissues

The fabric consists of two layers bonded together with adhesive substances. It is the tissues that are responsible for the functions that the jellyfish’s body can perform. We will consider which functions in the form of a list:

• The outer part of a jellyfish. The cells located here are responsible for the “motor apparatus”, prolongation of the genus. This part looks smooth and is convex;
• Interior of a jellyfish. The cells that are located in this layer are intended only for digestion. This part looks like a bag.
• The mouth is located at the bottom of the dome. He is the one distinctive feature each type of jellyfish, since, being in the middle, it is very different in structure;
• Special attention should be paid to the consideration of the umbrella, or rather its surroundings. There are tentacles here, which are also varied in appearance. They can be thick and long or short and thin, long and thin, almost thread-like, etc.

Jellyfish are very common and the most amazing view living creatures inhabiting the seas and oceans. You can admire them endlessly. What types of jellyfish are there, where they live, what they look like, read in this article.

General information about jellyfish

They belong to the coelenterates and are part of their life cycle, which comes in two stages: asexual and sexual. Adult jellyfish are dioecious and reproduce sexually. The role of the male is to sweep reproductive products into the water, which can immediately enter the corresponding organs of the female or be fertilized directly in the water. It depends on the type of jellyfish. The emerging larvae are called planulae.

They have the ability to exhibit phototaxis, that is, they move towards a light source. Obviously, they need to stay in the water for some time, and not immediately fall to the bottom. The freely mobile life of planulas does not last long, about a week. After this, they begin to settle to the very bottom, where they attach to the substrate. Here they are transformed into a polyp or scyphistoma, the reproduction of which occurs by budding.

This is called asexual reproduction, which can continue indefinitely until favorable conditions for the formation of jellyfish. Gradually, the body of the polyp acquires transverse constrictions, then the process of strobilation occurs and the formation of young disc jellyfish - ethers.

They are most of the plankton. Subsequently, they mature and become adult jellyfish. Thus, for asexual reproduction - budding, the water temperature may be low. But, having overcome a certain temperature barrier, dioecious jellyfish are formed.

Class of hydroid jellyfish

Coelenterates include solitary or colonial aquatic inhabitants. Almost all of them are predators. Their food is plankton, larvae and fry of fish. Coelenterate species There are ten thousand species of jellyfish. They are divided into classes: hydroid, scyphoid, and the first two classes are usually combined into a subspecies of jellyfish.

Hydroid coelenterate jellyfish are characteristic representatives of freshwater polyps. Their place habitual habitat are lakes, ponds and rivers. The body has a cylindrical shape and the sole is attached to the substrate. The opposite end is crowned with a mouth with tentacles located around it. Fertilization occurs inside the body. If a hydra is cut into many pieces or turned out the other way, it will continue to grow and live. The length of its green or brown body reaches one centimeter. Hydra does not live long, only one year.

They are free-swimming and have different sizes. The size of some species is only a few millimeters, while others are two to three meters. An example is cyanea. Its tentacles can stretch up to twenty meters in length. The polyp is poorly developed or completely absent. The intestinal cavity is divided into chambers by partitions.

Scyphoid jellyfish can live up to several months. About two hundred species live in temperate and tropical waters World ocean. There are jellyfish that people eat. These are cornerota and aurelia, they are salted. Many species of scyphoid jellyfish cause burns and reddening of the body if touched. For example, chirodrofus even causes fatal burns in humans.

Jellyfish Aurelia eared

There are different types of jellyfish. A photo of one of them is presented to your attention. This is a scyphoid eared one. Her breathing is carried out throughout her transparent and gelatinous body, in which there are twenty-four eyes. Sensitive bodies called rhopalia are located along the entire perimeter of the body. They perceive impulses environment. It could be the light.

The jellyfish eats food and removes its remains from the body through the mouth opening, around which four oral lobes are located. They contain a burning substance that serves as a defense for the jellyfish and helps it obtain food. Aurelia is not adapted to life on land, as it consists of water.

Medusa Cornerot

It is popularly called the "Umbrella". The habitat of the jellyfish is Black, Azov and Baltic Sea. Cornerot fascinates with its beauty. The body of the jellyfish is translucent with a blue or purple edging, reminiscent of a lampshade or umbrella. Its peculiarity is that most often it swims on its side and has no mouth. Instead, small diameter holes are scattered on the blades through which it feeds. Cornerot lives and reproduces in the water column on great depth. If you accidentally come into contact with a jellyfish, you can get burned.

Unusual habitat

Scientists from Israel have proven that freshwater jellyfish are found in lakes in the Golan Heights. The children saw them for the first time. Then individual specimens were placed in a bottle and given to Professor Gofin. He studied them carefully in the laboratory. It turned out that this was a local colony of one of the freshwater hydroid jellyfish, which were described in England back in 1880. Then these jellyfish were discovered in a pool of water tropical plants. According to the professor, the jellyfish's mouth is surrounded by numerous stinging cells, with which it catches planktonic organisms. These jellyfish are not dangerous to humans.

Freshwater jellyfish

These coelenterate inhabitants inhabit the waters only of seas and oceans. But, there is one exception called the Amazon freshwater jellyfish. Its habitat is South America, namely the swimming pool large river on the mainland - the Amazon. Hence the name. Today, this species has spread everywhere, quite by accident, during the transportation of fish from the seas and oceans. The jellyfish is very small, reaching only two centimeters in diameter. Now it inhabits slow, calm and stagnant waters, dams, and canals. The food is zooplankton.

The largest jellyfish

This is cyanea or lion's mane. There are different types of jellyfish in nature, but this one is special. After all, that’s what he described Conan Doyle in your story. This is a very large jellyfish, the umbrella of which reaches two meters in diameter, and the tentacles reach twenty. They look like a raspberry-red tangled ball.

In the central part the umbrella is yellowish, and its edges are dark red. The lower part of the dome is endowed with a mouth opening, around which there are sixteen large folded oral lobes. They hang down like curtains. Cyanea moves very slowly, mainly on the surface of the water. It is an active predator, feeding on planktonic organisms and small jellyfish. Habitat: cold waters. Occurs frequently, but is not dangerous. The resulting burns are not fatal, but can cause painful redness.

Jellyfish "Purple Sting"

This species is distributed in the World Ocean with warm and temperate waters: it is found in the Mediterranean and Atlantic Pacific Oceans. These types of jellyfish usually live far from the coast. But sometimes they can form schools in coastal waters, and are found in large numbers on the beaches. Jellyfish are not only They are golden yellow or yellow-brown, depending on their habitat.

Jellyfish Compass

These types of jellyfish chose their place of residence coastal waters Mediterranean Sea and one of the oceans - the Atlantic. They live off the coast of Turkey and the United Kingdom. These are quite large jellyfish, their diameter reaches thirty centimeters. They have twenty-four tentacles, which are arranged in groups of three each. The body color is yellowish-white with a brown tint, and its shape resembles a saucer-bell, which has thirty-two lobes, which are colored brown at the edges.

The upper surface of the bell has sixteen brown V-shaped rays. The lower part of the bell is the location of the mouth opening, surrounded by four tentacles. These Their poison is potent and often leads to the formation of wounds that are very painful and take a long time to heal.

Hello my dear friends! In order to maintain our erudition at the proper level and not let us relax over the summer, I propose a topic from the field of knowledge. The material will later be useful to our children in lessons about the world around them.

And today we will talk about sea jellyfish. Do you agree? Moreover, those who still have a trip to the sea ahead may be interested in combining theory with practice by getting acquainted with these amazing inhabitants water element closer.

Lesson plan:

Who is she, this unknown little animal?

Marine animals with streamlined shapes, similar in appearance to an umbrella, with many tentacles, have been living among us for a long time. The name of these sea miracles was given in the 18th century by Carl Linnaeus, who was well familiar with the Homeric legends about the mythical gorgon Medusa.

He noticed a certain resemblance to the head of this evil ancient Greek maiden, whose hair was composed of many moving snakes. It is because of this similarity between the tentacles and her head that the animal received its name.

And today, those who have visited the sea more than once have probably met them in the process, trying to swim around this living creature side. And all because jellyfish have special stinging cells with which they “bite” painfully, mercilessly burning us, as well as their prey and the predators attacking them.

Do you know what?! Medusa with unusual name Turitopsis Nutricula is considered the only immortal creature of its kind on our planet. And on average, almost all jellyfish live no longer than six months; long-livers last up to three years. Only a few species do not die, but are reborn into a new living organism.

Speaking in the language of zoologists, these sea ​​creatures- none other than coelenterates, members of the group of multicellular invertebrates. That’s why they spread so shapelessly, like jelly, when they fall on a hard surface or into our hands - there’s nothing for the fabrics to hold on to!

What, what, what are our jellyfish made of?

What does a skeletonless jellyfish consist of? Yes from the water! And by 98 percent! Therefore, if you put it to bask in the sun, it will almost all melt and dry out. And its muscles help it move in the water.

There are tentacles at the edges of the jellyfish's body. They can be long and thin, while some have short, thick “legs”. Based on these very tentacles, zoologists divide them into species. But no matter how many “legs” this invertebrate has - four or one hundred and four - their number is always a multiple of four. Why? This is how nature arranged it - this feature in such animal representatives is called radial symmetry.

It is on these very tentacles that those unfortunate stinging cells containing burning poison are located.

Do you know what?! The jellyfish called Sea Wasp is considered the most poisonous in the world among its relatives. This invertebrate “biter” the size of a basketball has such strength that it can kill 60 people at once in a couple of minutes!

The jellyfish breathes underwater with its entire body, and looks at those around it with 24 eyes, which are light-sensitive cells. True, scientists say that these invertebrates cannot distinguish objects, but they can distinguish light from darkness.

But thanks to these special cells, many specimens glow beautifully in the dark. Those that live higher to the surface of the water can wink in red, and those that prefer to hide in the depths often warn of their presence with blue light.

Jellyfish also have a mouth. It is located in the lower part and may look like a tube for some, like a club for others, and for others it can simply be a wide hole. By the way, because the jellyfish eats, it also throws the remaining food into the water.

A jellyfish has a lot of things, but it doesn’t have a brain! Nature did not reward the primitive creature it created with the ability to think, reflect, dream, and it did not provide sense organs.

How does a jellyfish live?

Jellyfish can live exclusively in salt water, so you will never see them in fresh rivers and lakes. But the oceans and seas, and not necessarily warm ones, there are those that like colder water - this is theirs favorite place residence.

This creature grows throughout its unconscious life and, depending on the species, can be small, just a few millimeters, or huge, as much as two meters. Some individual specimens can weigh several centners! Such a straight Bolskhansky floating jellied meat!

Do you know what?! If we measure the size of a resident of the North-West Atlantic called Cynea (in English Cynea) along with its tentacles, we get a figure of almost 40! meters.

This creature without brains and skeleton is a real predator! The largest ones catch small fish and even eat their own relatives. Smaller specimens are content with crustaceans, fish fry and caviar. “How does a jellyfish, which cannot distinguish any outlines, look for food?” - you ask. With the help of those most terrible and dangerous stinging cells on the tentacles, which catch touches and without thinking, since they have nothing to think about, they instantly inject poison into the victim. The jellyfish thereby paralyzes the prey, and then begins to feed.

Now you understand that when you touch the body of a jellyfish while swimming, in the first seconds it sees you as another lunch or dinner, burning you with poison! Some use the tentacles as a net to catch, entangling prey in them.

Scientists have noticed that jellyfish are solitary by nature. Of course, who would be friends with such gorgons! If you see colonies of clustered umbrella caps, then they have gathered together not at all because they want to “drink tea and talk.” They were simply overwhelmed by the flow of water. So they prefer to keep their distance from each other.

What types of jellyfish are there?

As we already mentioned, they are divided into types based on their tentacles. So, these are their families.

In total, in the nature of the world's oceans there are more than two hundred varieties of jellyfish of all shapes and colors. There are completely transparent ones, and red ones, and purple ones, and even speckled and striped ones, but there are no green ones! Why is unclear...

In general these natural creatures amazingly beautiful, especially when you watch them from the side, slowly floating through the water. Do you have any doubts? Hurry up, go to the aquarium and admire this beauty. No nearby? Then the Internet will always help you touch the beauty from thousands of kilometers away!

That's probably enough erudition for today?! It's time to relax, because it's still summer!

Although a video about jellyfish probably wouldn’t hurt)

Have a great August!

Probably each of us has met jellyfish while vacationing at seaside resorts, and usually meeting with these underwater inhabitants doesn't bring anything positive. But you will be surprised at how beautiful and diverse these spineless inhabitants of the seas can be.

(Total 27 photos)

Post sponsor: The era of digital free television in every corner of Russia without a “dish”. Details on the website d-color.ru

1. Jellyfish can be flat or elongated, but the most common jellyfish have a dome-shaped body.

2. Their sizes also vary - jellyfish can be very tiny and can grow up to two meters in diameter, and their bundles of tentacles can reach a length of 30 meters.

3. There are also colorless, almost transparent individuals, but the “nightlight” jellyfish amaze with their beauty, striking even experienced sailors with their beauty, not to mention ordinary people.

4. Jellyfish are one of the the most ancient representatives animal world: they appeared more than 650 million years ago. This means that they older than dinosaurs and sharks.

5. Jellyfish have still not been fully studied, because some types of jellyfish live at a depth of up to 10 thousand meters.

6. Today in some countries, such as Japan and China, jellyfish are eaten.

7. Jellyfish are approximately 95% water, 3-4% salt and 1-2% protein. They also have no heart, no eyes, no circulatory system, no gills.

9. The weight of large jellyfish can reach up to two centners, but one way or another, jellyfish are not able to resist the current.

10. Depending on the type of jellyfish, their color can be white, pink, yellow, orange, red, blue, green and multi-colored.

11. Jellyfish are able to navigate and hunt in pitch darkness.

12. Most jellyfish consist of three parts: a gelatinous body; tentacles that sting and catch prey; and an openwork mouth that absorbs food.

13. The jellyfish got its name because of its resemblance to the moving hair-snake of the legendary Gorgon Medusa from Greek mythology.

14. Jellyfish seem to be supernatural creatures largely due to their strange shapes and colors. Nature created them in a special way: their body resembles an umbrella, or a bell, sometimes a ball

15. Jellyfish can live at a depth of about 10,000 m. Scientists still know very little about jellyfish, in particular, how a creature without a brain can navigate in pitch darkness and actively hunt.

16. Jellyfish are often used in medicine. Even in the Middle Ages, diuretics and laxatives were made from cornet. And now medicines are produced from the venom contained in the tentacles of jellyfish to treat pulmonary diseases and regulate blood pressure.

17. Jellyfish help fight stress! In Japan, jellyfish are bred in aquariums. The smooth, leisurely movements of jellyfish calm people, although keeping jellyfish is very troublesome and expensive.

18. Box jellyfish or as it is also called - sea ​​wasp, kills every year more people than any others sea ​​creatures. Its bite can kill in 3 minutes!, and it can swim at a speed of 2 meters per second

19. The largest jellyfish in the world is considered to be the Arctic one giant jellyfish(Cyanea capillata aretica), found in the northwest Atlantic. One of the representatives of this species, washed ashore in Massachusetts Bay, had a bell diameter of 2.28 m, and its tentacles extended 36.5 m.

Smooth light movements of jellyfish hovering in deep sea, filled with majestic grace. It would seem, what could be special about a creature whose main component of the body is water?

Indeed, the body sea ​​predator, which is known as jellyfish, contains at least 90% water - sometimes the percentage of liquid content reaches 98%! A jellyfish thrown ashore loses its shape and spreads like a transparent drop over the rocks and sand.

Big and small

In water, an animal is constantly moving - isn’t this the best confirmation of the expression that life is movement? However, there is a type of static jellyfish - staurojellyfish, which are sessile animals.

The size of the predator can vary significantly depending on the species. Giant specimens of the “lion’s mane” are known ( arctic cyanea), the length of the tentacles exceeds 30 meters. The smallest jellyfish does not even reach 10 millimeters in diameter.

Beautiful and homely

If we gather representatives different types, it will seem that an amazing mosaic of multi-colored jelly is laid out in front of the audience. What shades does the color of a sea jellyfish take? The transparent base can take on yellow-orange, magenta, violet, burgundy, blue.

There are fantastic specimens that look more like tropical flowers rather than animals. Only green jellyfish have not yet been found. The color of the jellyfish may be uneven - then the pattern takes the form of bizarre stripes or specks.

Dangerous and safe

Most often found in the Black Sea blue jellyfish Cornerot, belonging to the order Scyphoid. The touch of the stinging tentacles of the cornet causes severe burns and can provoke allergic reaction, but generally not dangerous to human life.

Another representative of the animal of the same color belongs to the box jellyfish - the Australian pale blue Chironex fleckeri, an extremely dangerous poisonous predator. The body of Chironex fleckeri is a bell the size of a ball; the hunting tentacles can extend up to three meters.

Since this jellyfish is difficult to distinguish in sea ​​water Due to its discreet coloration, the box jellyfish poses a serious health threat. The toxin affects nervous system, disrupts the functioning of the heart.