The spider continues to weave a web from it. How and why a spider spins its web

Most types of spiders spin webs, but not all, such as tarantulas. Many tarantulas burrow into the ground and release a bit of web, covering the entrance to the "cave" to make it easier to catch flying insects. All spiders, whether they spin webs or not, have several common features: they have eight legs, they all feed on insects. Remember that spiders themselves are not insects.

Spiders belong to arachnids, or arachnids - these are animals that belong to the same group as ticks and scorpions. There are about 40 thousand species of spiders.

Why is a web needed?

They can weave very simple products, or weave real works of art. Even when the web is ready, the spider does not settle in it forever. The spider itself can lurk under roofing shingles or in the corner of a window frame, or under a rock. The purpose of the web is to catch insects. It may take several hours to weave a quality web.

How do spiders weave webs?

For example, a weaver spider uses several types of threads to build a web. To create a foundation, so to speak, a frame, he highlights a dry web. And in order to catch insects, the weaver puts a sticky web on the base. The web thread (a kind of "silk") is secreted by special glands on the spider's abdomen. Various glands secrete Various types silks. The spider can, depending on the purpose of weaving the web, use one or another web material.

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The round spider begins weaving the web, throwing the thread into the wind. The silk flies in the wind and clings to something, such as a tree branch, which allows the spider to climb up this thread and add another thread to the original one to make it stronger. After the spider has made the general contours of the web, he spins a thread connecting one side of the web to the other. From the center of this connecting thread, the spider begins to weave another thread that will connect the center of the web to the side thread.

Then the spider will put a lot of connecting dry threads from the edges of the web along its radii to the center, like spokes in a bicycle wheel. Then these "knitting needles" are braided with circular threads. It turns out a spiral dry web. Then an adhesive thread is applied to the surface of the dry web. Now the spider gets rid of the dry web - eats it. The fishing gear is done, the insect snares are ready.

Interesting fact: some webs may be more difficult, others easier.

Web design

The design of the web, according to experts, varies depending on the method of hunting. To us, the entire web seems to be the same and made up of completely standard elements. Such a deceptive impression is created because we do not see the web in ultraviolet light.

Why does the web attract insects?

Ultra-violet rays - component sunlight, and it is the part that forms the tan of the skin. But the frequency of ultraviolet waves is too high and is not perceived by our eyes, so for us it is an invisible light. However, many insects are able to see ultraviolet rays, especially those that feed on flower nectar and pollen. Many spiders weave a web that attracts these insects to them. How it's done? First, the spider weaves a web of threads that almost do not reflect ultraviolet rays. Then he weaves a different type of thread into the web structure, which shines brightly in ultraviolet rays.

Seeing a spider, many of us get scared, try to destroy it. And the cobwebs that hang in the corners, on the trees?
Why and how does a spider weave it?

Let's try to figure this out.
Firstly, in the abdomen of the spider there are arachnoid glands that produce a sticky secret that solidifies in the form of threads in the air, and the abdominal limbs with movable warts form a thread, and then a fiber from the threads. With the help of comb claws and bristles on the limbs, the spider quickly glides along the web.

Why does a spider need a web:

Like a net for catching, because they are real predators. Because of the viscous liquid, a lot of living creatures from insects to birds get into their net.

When a victim falls into a trap, the victim swings the web, and the vibrations transmit a signal to the spider. He gets close to the trophy, sprinkles the digestive enzyme, coils the web into a cocoon and waits to enjoy.

For breeding
Male spiders knit lace next to the female's web, then tap with measured limbs to lure females for mating. And the female allocates a thread that helps to find an individual for mating. He, in turn, attaches his web to the main threads and signals to the chosen one that he is here, she, without aggression, descends along the fastened web to mate.

For movement
There were cases when they saw spiders on a ship located on the high seas.

Individual instances use the web as a means of transport. They climb high objects and release a sticky thread that instantly hardens in the air; and a spider flies on a cobweb with a headwind to a new place of residence.
Not very large adult spiders can climb up to 2-3 kilometers in the air and travel like that.

Like insurance
For jumpers, the web thread serves as insurance against predators and to attack the victim from it.
At South Russian tarantula a barely noticeable web thread always stretches to find the entrance to its mink. If suddenly the thread breaks, and he lost his house, he begins to look for a new one.
And the jumper can sleep at night, thus escaping from enemies.

As a haven for offspring
To lay eggs, the female weaves a cocoon from arachnoid fiber, which provides reliability for future offspring.
The plates (main and covering) of the cocoon are woven from silk threads impregnated with a solidified substance, so they are very durable, similar to parchment.
There are cocoons that are loose and look like a cotton ball.

For lining
The tarantula covers the walls of its minks with a net so that the walls do not crumble, and builds an original mobile cover on the inlet.
catch prey

How does a spider spin its web? He has been doing this for over 200 million years. Each of the 42 thousand species does this according to an individual scheme: a classic wheel-shaped net, a hammock, a canopy or single thread traps.

Nature has provided these animals with a unique spinning machine. Scientists still cannot accurately reproduce its design and the composition of the produced threads.

Where is it formed and where does it come from?

Spiders and their webs are one of a kind a natural phenomenon. The weaving process resembles the production of cotton candy - a pre-mixed composition is drawn from a narrow opening of the tank and hardens in air in the form of a thin thread.

The belly of the animal serves as a container, and the secret produced by its internal arachnoid glands serves as the material.

In the lower part of the body of the spider (opistome) there are from 1 to 4 pairs of growths - arachnoid warts. In some species, these outgrowths are mobile and at the same time perform the function of an organ of touch. This is the area where the spider web appears.

Part of the surface of the warts is dotted with small hairs - spider webs. Each of them is the output duct of the internal gland and consists of two parts - thick (basal, internal) and thin (forming, terminal). The area with the tubes is called the arachnoid field.

Along with the tubules, chitinous cones, also located on the surface of the warts, are involved in the production of the web. They open larger glands.

Thread selection is controlled by a central nervous system spider. Thickness, stickiness and even shade can vary.

To do this, various types of glands are involved in the weaving process, for example:

• tubular - release threads for the egg cocoon. Males do not have this type of gland;
• ampoule - produce dry thick threads for the base of the network;
• pear-shaped - strong thin fibers for attaching the web to the base;
• lobular - double silk fiber, the basis of the spiral threads of the trapping net;
• tree-like - emit glue to cover the base, which does not harden upon contact with air. With a strong increase on the threads, droplets will be noticeable - the sticky secret of the arborescent glands. It is on them that moisture is concentrated during rain.

Each species of spider has its own set of glands. Switching from one to the other takes about a minute. The cross spider spins its web using 6 glands. There are 480 to 560 tubules and about 20 cones on its spider webs.

How spiders weave webs

All types of spiders prefer to weave webs or stretch thread traps at night. At this time, optimal conditions are created: there is no heat, wind, sunlight, the air is sufficiently humidified.

To fix the thread to any surface, the spider presses the warts to it, and then crawls away, dragging the hardening fiber along with it.

The thread is pulled with the help of the hind legs, its tension and position are simultaneously regulated.

How a spider-cross weaves a web:

1. The spider chooses a place, releases the thread and waits until it catches on the support in free soaring. The distance between the attachment points can reach 2 m or more.
2. Then the animal crawls to the other side of the thread, fixes it, returns about 1/3 of the distance and hangs down, releasing another thread, which it fixes at an angle to the support located below.
3. The spider along the inclined thread returns up to the supporting one, simultaneously releasing a new fiber, but not fixing it. The end will be fixed to the support thread closer to its opposite end. In this way, a web frame is built in the shape of an inverted triangle. There may be options in the form of a square or an irregular polygon.
4. Internal radii are built in the plane of the frame (from 30 to 50). The spider does not stretch them through a single point in the middle, but attaches them to a dense arachnoid plexus. Upon completion, he returns to the center and begins to connect the radii in a circle with temporary auxiliary jumpers (provisional spiral). The time spiral has few turns, the distance between them increases when approaching the edge of the frame.
5. Once on the periphery, the spider turns around and begins to weave already permanent jumpers (trapping a spiral of adhesive thread), biting the temporary ones and rolling them into lumps. The movement takes place in a narrowing spiral from the edges to the center. The distance between the turns is already the same (“Achimedes spiral”).

Any object caught in a trap is carefully examined, then either dropped or twisted into a cocoon. The spider itself does not stick to sticky fibers due to special hairs on its paws.

Not all spiders weave a trapping web. Some species hang on a strong web fiber, waiting for the victim, then pounce on it and quickly entangle it. Others sit in a hole and wait for signal threads stretched nearby to vibrate.

Some weave nets in the form of a canopy, placing them horizontally. Such a web rests on threads passing through it, fixed from above and below.

Video

Spiders tune their web like a guitar

The composition of the web

The basis of the web (2/3 of its composition) is water-insoluble protein fibroin (fibrillar protein). This is the substance that gives the spider's web increased strength. It consists of a complex of simple proteins (albumins), d-alanine (amino acid), glutamic and aminoacetic acids.

The stickiness of the web is provided by sericin (a substance of protein origin, silk glue). IN chemical composition cobwebs also include potassium nitrate and hydrogen phosphate, which provide protection against bacteria and fungi.

Depending on the type of glands used, the spider produces about 7 varieties of fibers of different chemical composition, from which it weaves the structural parts of the web.

The structure of the thread is not uniform. It is made up of rigid protein crystals, firmly connected by elastic ligaments. In terms of chemical composition and properties, the web is similar to silk. silkworm, but the spider is stronger.

The thread retains tensile strength, does not twist even with prolonged rotation. The last property is called "hingedness". sunlight, hot and dry air weaken the strength of the thread.

The role of the web in the life of a spider

The web is not only a trapping net with which the spider entangles its prey. Her role is much more important. The realization of the instinct of reproduction is one of the main goals, which is why spiders weave their web. Females use it to attract a male, leaving pheromones on the threads.

Male araneomorphic spiders in the vestibule mating season a special spermatic mesh is woven, on which seminal fluid is isolated for subsequent transfer to a special reservoir on the forelimbs-tentacles (pedipalps). They are also the organ of copulation.

From the web also egg cocoons are woven. Some of them have a very complex barrier structure. The bacteriostatic properties of the web protect the eggs from the effects of molds, bacteria and drying out.

Another reason why spiders need webs is protection. Adults hide in web cocoons during periods of molting. At this time, they are most vulnerable, and a dense breathable cover reliably protects against external factors.

Water spiders create a cocoon from cobweb threads to collect air bubbles. Many species cover the walls of their dwelling with fibers, braid the entrance to it.

Most people don't like spiders. They look rather unpleasant, and prejudices do their job. At the same time, not only children, but also adults have a keen interest in how a spider weaves its web. Why he does this is clear to everyone. But how, remains a mystery. Let's try to open it.

You won’t believe it, but not all spiders are capable of creating such an elegant lace, but only those that use it to catch small insects that serve them as food. These representatives of the spider family are called snails. They also include poisonous individuals, such as karakut and black widow. The same spiders that are actively hunting can also weave a web, but they use it purely for other purposes.

In humans, lace woven by spiders often causes a feeling of envy, they are so skillfully woven. The threads from which they are made are incredibly durable. From its own weight, the web never breaks. This can only happen if the length of the thread is more than fifty meters. As you can see, the margin of safety of cobwebs is very high. If you pay attention to their subtlety, then this fact can really be envied. If you take a separate cobweb and try to stretch it, then it will break only after it has quadrupled in length.

Threads woven by a spider have another exceptional property. They are transparent and almost invisible. Depending on the conditions of use, the spider can weave a web of three types: strong, household, sticky. A strong web is used to create a framework for trapping nets. Jumpers in the frame are made of sticky threads. With a household web, the spider closes the entrance to its mink or entangles cocoons with larvae. Some types of spiders can spin webs that reflect ultraviolet rays. It is used to attract butterflies.

Do all spiders weave patterned webs?

As it turns out, not all. Only araneomorphic arthropods are capable of creating real masterpieces.

Now let's get back to the question of why a spider needs a web. It is clear that the answer suggests itself - of course, for hunting. However, these are not all of its functions. The web can be used for the following purposes: for masking and warming the entrance to the hole, for cocoons, for protection. Paradoxically, the cleverly crafted web protects the spider's burrow from the rain. Spiders move along the web, their offspring leave the nest along it.

And yet, what is the basis of the web?

The spider has six glands located on its abdomen. With their help, he produces a secret called liquid silk. When it comes out, it starts to harden. Incredibly thin threads emerge from the glands, which the spider twists together with its paws. The result is a web. This is how he weaves his lace.

If this is a trapping net, then he stretches it between the branches of the tree. Having fixed one side of the thread, he stops spinning and waits for a breath of wind, which should carry the second side of the web to the second branch. After that, the next stage of weaving begins, which is similar to the first. This continues until the framework of the future network is woven. After that, a sticky web is woven into it. All unused remnants of the web are eaten by the spider.

Almost all spiders are predators and use their webs to catch insects. Shadow spiders catch flying insects. Those who live in earthen burrows are content with beetles, worms and snails. Water spiders catch small fish, crustaceans, insects. The tarantula does not disdain frogs, lizards, birds, small rodents. However, there are those who eat their own kind.

In summer, starting from July, and especially in autumn, on the grasses, even on the lawns of parks, on low bushes and young pines, it glitters with dew splashed, thrown between the branches, like silk scarves - the finest work! Delicate, graceful and densely woven web. It is different, very different, and because the trapping net is arranged, you can immediately decide which spider wove it. Spiders produce a web of different varieties: inextensible and elastic, dry and sticky, with sticky droplets, straight and corrugated, colorless and colored, thin and thick, and some even weave real ropes.

Many researchers, hour after hour, day after day, sat at the web constructed by the spider, Andre Tilkin, the French philosopher, devoted 536 pages to the web, although even 11 years before him, the German G. Peters seemed to have seen and told everything that can only be seen and told about the web of the cross. And even now, for an inquisitive mind, the web is fraught with so much new and unexpected that it is worth sitting in front of it for more than one hour. T. Savory said that: "Weaving circular networks is a performance that can be watched and watched."

Once I saw an amazing web, and next to it a small spider, I wondered how such small spiders can create such beauty and how do they do it? Conducting observations of spiders and cobwebs, I set myself the goal: to study the features of spider webs, the adaptations of spiders to create cobwebs.

I was interested in the following questions:

1. Is it true that the web is a pure protein?

2. Do all spiders have the same web?

3. How does a spider weave its webs?

4. What properties does the web have?

5. Find out what a “signal thread” is. And its meaning.

To find answers, I set myself the following tasks:

1. Study literature.

2. Conduct observations in nature for spiders and cobwebs (take photographs).

3. Carry out simple chemical experiments in the school laboratory.

4. Find similarities in the schematic drawings of cobwebs with those found in nature.

1. MAGIC WEB

1. Skillful weavers

From what and how does a spider pull its web? On the abdomen of the spider, at its very end, there are spider warts. This is what made the spider a spider.

Nature works wonders, turning the juices of a spider's body into a web. five or six different types spider glands - tubular, sac-shaped, pear-shaped - produce a web of several varieties. And her purpose is directly universal: nets and nets make her a spider, a cocoon for eggs and a house for living, a hammock for mating purposes and balls for throwing at a target, a diving bell and a bowl for food, nooses for flies, ingenious doors for holes, and for a kind of parachute when moving with the wind. On the hind limbs of the abdomen, the ducts of the spider glands open. These legs are called spider warts. With their help, the spider weaves its wonderful trapping webs. Each spider gland brings out its products - a sticky liquid, quickly hardening - through a thin chitinous tube. There are half a thousand of such tubes in the cross, and only a hundred in the spider that lives in the cellar. Spinning tools for spiders are not the same. The first pair of walking legs is the longest. With its help, the spider spins a web and communicates with its fellows. Spider thread bases are silk squirrels.

Weave: genuine art

The circular network of spiders is a very intricate thing, and its construction is not at all an easy task. Special materials and special weaving methods are used here, thought out. The spider himself thinks little about weaving a web: all his actions are entirely instinctive. The network woven by each of them has an individual pronounced character. On the web, you can find out which one, the spider wove it. The methods and main principles of building a network are almost the same for everyone. First of all, from what structures is it assembled?

There are eight of them: a frame of the first order, a frame of the second order, radii, a center, fastening spirals, a zone free from spirals, trapping spirals and auxiliary spirals, from which only nodules remain on the radii of the finished network - at the places of the former intersection of the radii and auxiliary spirals. The frame threads, especially the upper threads, are thick and not very elastic. The radii are also inelastic, while the trapping spirals, on the contrary, are very elastic - they can be stretched twice or four times, and then, as soon as the deforming force has weakened, they again shrink to their previous length. All threads are dry, except for trapping spirals, densely hung with glue droplets. That's why when I touched the web with my hands, it stuck to my fingers.

First, he stretches the frame of the first order. Its basis is usually two threads. They converge at a wide angle at one point, and from it they can diverge up or down - it all depends on the location of the spider. The spider, having glued the thread at the top, descends, vertically, hanging on it, to a solid object at the bottom, gluing the thread to it, and crawls up it again, not forgetting to pull the second thread out of the warts. So that she does not stick together with the first one, on which he crawls, he holds between them an additional claw of one of his fourth legs. Having risen to the starting point, he runs to the side - to the width of the upper base of the frame - and there he glues the thread that he pulled behind him. The cornerstone of the network, or the frame of the first order, is ready. It remains to weave additional threads into it so that it is stronger: after all, the whole network hangs on it. How are radii weaved?

The spider climbs to the highest point of the constructed frame, where it glues the beginning of a new thread, which will be the first diameter of the circle. It falls, pulling it down with its weight from the glands to the lower edge of the frame. Glues a thread to the frame - an elevator and crawls up it to the future center of the circle. Here the thread that was pulled along, crumples and presses into a lump and hangs it on the thread along which it crawled - this is the center of the center of the web. It crawls up again by inserting a claw between the threads (along which it crawls and pulls along), runs to the side and glues the towed web on the frame - the first radius is stretched from the center of the diameter to the frame. It crawls along it again to the center, from the center - pulls down along the diameter. The thread that it is pulling behind itself does not allow now to stick together with those held before. Having reached the lower edge of the frame, he runs to the side and ties the second radius there, on the frame. So, running alternately down and sideways, then up and sideways, tightens the entire frame with radial threads with the same angles between them. The third and, incidentally, the fourth (the center crossed randomly by threads) composite structures of the trapping net are completed.

The fifth - fastening spirals - the spider does quickly: returning to the center and from it from radius to radius, throwing them. The sixth zone, free from spirals, arises by itself, since you don’t need to work on it, just make sure that you don’t braid it by mistake. But the seventh and eighth structural elements require a lot of effort and attention.

The spider weaves trapping spirals from the outside to the center. To do this, he needs scaffolding on which he can spiral. They serve as auxiliary spirals; their spider weaves from the center to the edges. Moving along the auxiliary spirals from the frame to the center, with the first pair of legs, he measures the distance between the turns of the trapping spirals, which he pulls and fixes on the radii with the legs of the fourth pair. On the second and third legs it runs along the web. Trapping spirals are woven from a special material - cobwebs, thickly smeared with glue. As soon as the scaffolding-auxiliary spiral fulfills its purpose, the spider, having run about one circle along it, bites and eats it (so that the protein from which they are made does not go to waste). Therefore, by the end of the work, only knots remain from the spirals.

Spiders are forced to handle the cobweb fluid with care, since it is produced in spiders only when good nutrition and is costly to the animal. Once released and hardened, the web can no longer be retracted. Sometimes you can see that the spider, rising up, seems to absorb the web, which is getting shorter; but upon closer examination, it turns out that the spider simply wraps it around its legs or around its torso.

1. 3. As strong as steel!

Spider webs, or nets, are extremely diverse in design, but the principle of their operation is the same: the insect lingers, as indicated by the fluctuation of the web threads, their displacement or even rupture. In the flat wheel-shaped web of the cross-spider, there is no such dense interweaving of threads as in a three-dimensional web, so it is possible to keep prey thanks to no longer a design, but special properties fibers. They are strong enough and do not tear when strongly stretched, do not spring. The fibers of such a web can quickly contract and stretch 4 times or more.

What is the reason for such amazing properties of threads? It is based on the protein keratin, which is part of the hair, wool, nails and feathers of animals. The structure of the fibers of the web, when stretched, the threads straighten, and when it is released, they return to their original position, i.e., the elasticity of the spring.

We can say that the spider web in its strength and elasticity is superior to natural silk. Its tensile strength, according to D. E. Kharitonov, is approximately 175 g/mm2 versus 33-43 g/mm2 for natural silk and 18-20 g / mm2 for artificial. The web of a spider is thousands of times thinner than a human hair. The fineness and strength of the fiber is measured in units called denier. Denier is the weight in grams of a thread 9 kilometers long. A thread silkworm weighs one denier, a human hair is 50 denier, and the thread of a spider's trapping web is only 0.07 denier. And this means that the web thread, which can be encircled along the equator Earth, weighs just over 300 grams. Gossamer is twice as strong as steel, stronger than orlon, viscose, ordinary nylon, and almost equal to special high-strength nylon, which, however, is worse than it, because it is much less stretchable and, therefore, breaks faster under the same load. Silk thread is one of the strongest chains in the world. Elastic, it can stretch, becoming twice as long as before, and at the same time it does not tear. Despite such a tiny diameter, it is as strong as steel! Synthesizes spider web from amino acids. It's pure protein!

2. PRACTICAL PART

EXPERIMENT No. 1. Purpose: to determine whether the web sinks in water.

Devices and materials: a container with water, cobwebs.

Course of experience: lowered the web into cold water. The web didn't sink.

Conclusion: It is of protein origin and belongs to the group of globular proteins that are insoluble in water and are not wetted by it.

EXPERIMENT No. 2 Purpose: to determine whether the web dissolves in 70% acetic acid.

Equipment and materials: glass cup, 70% acetic acid, spider web.

The course of the experiment: the web was placed in a glass cup, 70% acetic acid was dropped. The web didn't dissolve. 15 minutes passed, the web did not dissolve, after 30 minutes the web did not dissolve either. After 6 hours of experience, the web did not dissolve. Another 18 hours passed - the web did not dissolve.

Conclusion: the web does not dissolve in 70% acetic acid. But the material (web) curled up into a ball, which means it is pure protein.

EXPERIMENT No. 3 Purpose: to determine whether the cobweb dissolves in baking soda.

Equipment and materials: glass cup, baking soda diluted with water, cobwebs.

The course of the experiment: the web was placed in a glass cup, drinking soda was dripped with diluted water. The web didn't dissolve. 5 minutes passed, the web did not dissolve, after 30 minutes the web did not dissolve either. After 4 hours of experience, the web did not dissolve. Another 12 hours passed - the web did not dissolve.

Conclusion: the web does not dissolve in an alkaline environment.

EXPERIMENT No. 4 Purpose: to determine if the web is really a pure protein.

Instruments and materials: test tube, transparent nitric acid, pure white cobweb.

The course of the experiment: the web was placed in a test tube, nitric acid was dropped. cobweb dissolved nitric acid slightly yellowed.

Conclusion: the web is a pure protein.

EXPERIMENT No. 5 Purpose: to determine whether the web decomposes without air access.

Devices and materials: sealed plastic bag, branch with cobwebs

The course of the experiment: they placed a branch with a web in a transparent bag. The package was sealed tightly and hung on the balcony in the sun. We watched the web for a month. Despite the fact that the air temperature changed, the web did not change either in color or in shape, it remained the same.

Conclusion: the web is woven from a dense material. Air temperature does not affect fiber quality. The substance from which the web is formed does not oxidize in air, does not decompose without air access. So its chemical composition is pure protein.

EXPERIMENT No. 6 Purpose: to determine whether the web is of natural origin.

Devices and materials: matches, metal rod, cobwebs.

The course of the experiment: we fix the web on a metal rod with a wooden tip, set it on fire. She's on fire.

Conclusion: the web burns, not melts. So this is completely natural origin product without chemical impurities. With a specific smell of burning protein.

EXPERIMENT No. 7 Purpose: to determine whether the web does not deform when stretched. And does the web have a signal thread.

Devices and materials: ruler, branches, web.

The course of the experiment: we move apart the branches on which a web 2 cm in diameter is fixed, to the sides. The web stretched 0.5 mm wide. When we release the branches, the web returns to its previous position. We measure the web, it remained the same size and did not deform.

Conclusion: the web is elastic, does not deform and does not tear when stretched. This means that the thread consists of a long fiber, which the spider synthesizes from amino acids. In addition, the spider reacted to the movement of the branch - it appeared on its web, which means that the web really has a signal thread.

EXPERIMENT No. 8 Purpose: to determine whether the quality and appearance cobwebs temperature difference.

Devices and materials: sealed plastic bag, freezer, thermometer, spider web.

The course of the experiment: the web was placed in a sealed plastic bag and placed in a freezer, where the air temperature is minus 10ºС, for 24 hours. In appearance and quality (remained sticky), the web has not changed.

They hung the same package in the sun, where the air temperature was plus 20ºС, the appearance of the web did not change, remained the same. The quality of the web has not changed, it remains sticky.

Conclusion: the appearance of the web and its quality (stickiness) is not affected by a sharp drop in air temperature.

Experiment: I caught a fly, carefully planted it on the web, the fly stuck, buzzed and tried to escape. The signal thread twitched, the spider instantly ran up to the fly and approached from one side, then from the other side, doing something to the fly, and the fly began to subside, swaddled with cobweb threads. Less than a minute passed, and the fly was already tied up and did not twitch.

Conclusions: After conducting my observations, research, I found out that the spider never sits in the very center of its trapping web, it hides in some kind of shelter nearby. And from the network to the shelter, a cobweb necessarily stretches - a signal thread.

CONCLUSION.

Through experiments and observations, I came to the conclusion that the web is a protein. I learned that fiber contains amino acids that are highly hygroscopic. Protein chains are arranged along one axis and form long fibers, reminiscent of silk proteins in amino acid composition. By its origin, the web belongs to the group of globular proteins, it does not dissolve in water and is not wetted by it. This is a completely natural product of animal origin, it burns, not melts.

While working, I learned that the webs are different not only in size, but also in the woven pattern. Spider web squeezes out with different speed. That the web freezes instantly. The spider weaves a thread intermittently, since the development of a web takes a lot of energy: having developed 30-35 meters of thread, it restores strength within a few days. All crosses have different nets, although all crosses have round nets and look like lace. But the webs of house spiders are completely different, they are stretched in a corner, from wall to wall, without any order. Like thin gray patches. Those spiders that live in trees, in bushes, in grass, gossamer threads stretch from branch to branch, from leaf to leaf, from blade of grass to blade of grass, also without much order.

I learned that spider web is stronger than steel and more elastic than natural silk. Spider nets are used in a wide range of applications from socks to fishing nets, and were previously used as dressings.

You can still tell a lot of interesting things about the web and spiders. After all, spider webs and the silk fibers from which they are made have not been sufficiently studied. But for starters, I think that's enough.

And now every summer I will watch them lace and take pictures. Since in the future I dream of connecting my activities with medicine, my work and my observations will be useful to me in the future, both in my studies and in choosing a profession.

Maybe in the future, spider farms will be created to create children's environmentally friendly and harmless clothes for newborns. Someday we will not use chemical compounds to kill flies, but we will use a web that does not need to be disposed of (burned, buried in the ground) and harm nature.