Interesting features of the structure and behavior of reptiles. Reptiles (reptiles) and their representatives. Digestive system of reptiles

reptiles

reptiles - they are; pl. Zool. The name of a class of vertebrates, including snakes, lizards, turtles, crocodiles; reptiles.

reptiles

(reptiles), a class of vertebrates. Mixed circulation is characteristic; they breathe with lungs, body temperature is unstable, the skin of the majority is covered with horny scales or shields (protection from drying out). Modern reptiles include: turtles, crocodiles, beakheads (tuatara) and scaly ones (lizards, amphisbaena and snakes). Over 8000 species, mainly in hot and warm zones. Most live on land, some in the seas. They feed mainly on animal food. They lay eggs, some are ovoviviparous and viviparous. Meat and eggs of some reptiles are eaten. Various products are made from the skin of snakes, lizards and crocodiles. Many species (especially turtles, snakes and crocodiles) are in sharp decline. About 150 species and subspecies of reptiles are in the IUCN Red List. The most ancient reptiles appeared in the Middle Carboniferous. Having reached prosperity and great diversity in the Mesozoic (dinosaurs, pterosaurs, etc.), many groups became completely extinct by the end of the Mesozoic. Herpetology is the study of reptiles.

reptiles

REPTILES (reptiles; Reptilia), a class of vertebrates (cm. VERTEBRATES); distributed on all continents except Antarctica. Reptiles are characterized by mixed circulation; they breathe with lungs, body temperature is unstable, the skin of most is covered with horny scales or shields (protection from drying out). Currently, there are about 7-8 thousand reptiles, divided into 4 orders. These are turtles (230 species); scaly, the most numerous (about 6500 species), which include snakes and lizards; crocodiles (22 species) and beakheads, represented by a single species - tuatara (cm. GUATTERIA) living in New Zealand. Reptiles live mainly in hot and warm climatic zones.
Reptiles are the oldest animals that appeared for the first time in the Middle Carboniferous. Compared with amphibians, they represent the next stage in the adaptation of vertebrates to life on land. These are the first true terrestrial vertebrates, reproducing on land with eggs and breathing only with lungs. Reaching into the Mesozoic (cm. MESOZOIC ERA) prosperity and great diversity (dinosaurs (cm. DINOSAURS), pterosaurs (cm. PTEROSAURS) etc.), many groups became completely extinct by the end of the Mesozoic. Herpetology is the study of reptiles. (cm. HERPETOLOGY).
The body of reptiles is covered with scales, scutes, or other horny formations and, in most species, is devoid of skin glands. They breathe atmospheric air. Body temperature is not constant, it depends on the ambient temperature, and the activity of animals also depends on it. Crocodiles and many turtles live in fresh water, some snakes and turtles live in the sea.
Most species reproduce by laying eggs, but there are also ovoviviparous and viviparous species. The eggs are enclosed in a hard calcareous (in turtles and crocodiles) or parchment-like (in lizards and snakes) shell, which protects them from drying out. The incubation period is from 1–2 months to a year or more (in the tuatara). Rarely take care of offspring. The vast majority of reptiles are carnivores or insectivores. Some lizards (agamas and iguanas) are omnivores; terrestrial turtles feed mainly on plants.
In the 20th century, the number of certain groups of reptiles, especially turtles, snakes and crocodiles, sharply decreased due to the use of meat for food, leather and shells for the manufacture of various products, and the use of snake venom for medical purposes. To restore and preserve the number of reptiles, they are bred in captivity, breeding sites are protected and fishing is prohibited.
In captivity they contain lizards, snakes, turtles and even crocodiles. The soil in the terrarium (earth, sand, peat) and its moistening must correspond to the living conditions of animals in nature. For all animals, including desert dwellers, clean water should be in the terrarium (in drinking bowls, cuvettes, pools). All reptiles need shelter, and many species require humidity chambers. For normal life, they imitate the natural change in temperature, the length of daylight hours. For this, incandescent lamps and other devices are used, with the help of which during the day they heat the area familiar to animals, which can accommodate all the inhabitants of the terrarium. At night, the heater is turned off, which simulates a nighttime decrease in temperature.
In the cold season, for several weeks or months, they reduce the length of daylight hours and reduce the temperature of the content. For animals living in nature in a temperate climate, they imitate the state of wintering. Live frogs, small rodents, birds, worms, various insects, as well as carcasses of small animals, prepared and frozen in advance, serve as food. Fish, squid, shrimp, snails, less often meat are also used in feeding, they also provide vitamins. It is desirable to diversify animal food for carnivorous reptiles with vegetable food, and animal food must be added to herbivorous reptiles.
To get offspring in captivity, various methods of forming breeding groups are practiced. The best option is considered for turtles 2-3 males per 1 female, for lizards - 1-2 males per 3 females, for snakes - 2 males per 1 female. The female can be planted with a group of males or sequentially with several separately sitting males only during the breeding season. Eggs or emerging young are removed from the terrarium with adult animals. The eggs are kept in special incubators. The temperature and duration of incubation are different for different groups and species of reptiles.

encyclopedic Dictionary. 2009 .

See what "reptiles" are in other dictionaries:

Reptiles ... Wikipedia

reptiles, representatives of approximately 6,000 species of vertebrates, distributed throughout the globe. Reptiles are POIKILOTHERM (cold-blooded) animals. Most of them lay eggs rich in yolk on land. Some… … Scientific and technical encyclopedic dictionary

- (reptiles) class of vertebrates. Mixed circulation is characteristic; breathe with lungs, body temperature is unstable, the skin of the majority is covered with horny scales or shields (protection from drying out). Modern reptiles include: ... ... Big Encyclopedic Dictionary

Reptiles (Reptilia), a class of vertebrates. The most ancient P. cotylosaurs appeared in the Middle Carboniferous and still retained in their structure features characteristic of Paleozoic amphibians (stegocephalians). Later P. were divided into 2 ch. trunk ... ... Biological encyclopedic dictionary

Reptiles Dictionary of Russian synonyms. reptiles adj. reptiles Dictionary of Russian synonyms. Context 5.0 Informatics. 2012 ... Synonym dictionary

reptiles, theirs, sg. stinging, stinging, cf. The class of vertebrates moving predominantly. crawling or dragging their belly along the ground (snakes, lizards, crocodiles, turtles), reptiles. Explanatory dictionary of Ozhegov. S.I. Ozhegov, N.Yu. Shvedova. 1949 1992 ... Explanatory dictionary of Ozhegov

- (Reptilia) class of vertebrates. The skin is covered with horny scales or scutes, breathing is exclusively pulmonary, the blood temperature is unstable, the heart is three or four chambered, the arterial blood flow is mixed with the venous or in the heart, or ... ... Encyclopedia of Brockhaus and Efron

reptiles- reptiles, reptiles: breathe only air; breed only on land; mixed circulation; the skin of most is covered with horny scales; feed on predominately. animal food. turtles (land, freshwater, marine). hydromedusa. ... ... Ideographic Dictionary of the Russian Language

- (Reptilia) class of vertebrates. The skin is covered with horny scales or scutes, breathing is exclusively pulmonary, blood temperature is unstable, the heart is three or four chambered, arterial blood flow is mixed with venous blood either in the heart, or along ... ... Encyclopedic Dictionary F.A. Brockhaus and I.A. Efron

This lesson will cover the topic "Reptiles. Differences between reptiles and other animals. We learn about the first terrestrial real animals - the Reptile squad. They are well, with the exception of some, adapted to life on land. Consider the main differences between reptiles and other animals.

It consists of a head, body, paired limbs with claws and a long tail. In case of danger, some lizards can drop their tail. Lizard skin is covered with scales, plates, ridges. Their head moves well, their eyes have movable eyelids. Lizards respond well to moving prey, they hear well. Lizards have small teeth and a tongue in their mouths. This tongue is bifurcated, because it is perfectly adapted to hunting. It is also the organ of smell, touch and taste. The food of lizards is varied.

The yellowbell and the brittle spindle have no legs and look like snakes (Fig. 2, 3).

Rice. 2. Yellowbelly ()

Rice. 3. Brittle spindle ()

The agile, green, and viviparous lizards (Figure 4-6) are the most common.

Rice. 4. Quick lizard ()

Rice. 5. Green lizard ()

Rice. 6. Viviparous lizard ()

The marine iguana has mastered the water element, where it feeds (Fig. 7).

Rice. 7. Marine iguana ()

Basilisks have a very frightening appearance, they run on water as if on land (Fig. 8).

Rice. 8. Basilisk ()

The agama family includes the most bizarre lizards - a flying dragon (Fig. 9).

Rice. 9. Flying dragon ()

Moloch impresses with its large and sharp spikes (Fig. 10).

There are poisonous lizards (Fig. 11).

Giant monitor lizards live on Komodo Island (Fig. 12).

Rice. 12. Gigantic monitor lizard ()

Chameleons can change their color and body pattern (Fig. 13).

Rice. 13. Chameleon ()

The gecko can walk upside down (Fig. 14).

In nature, there is even a blue-tongued skink (Fig. 15).

Rice. 15. Blue-tongued skink ()

snakes are also scaly reptiles. They have a long cylindrical body with a tail. The head is usually facial or triangular in shape. Snakes have no legs, their body is covered with scales. Snakes move very well, crawl fast enough. The eyes of snakes are covered with a transparent film, they do not see well and do not hear very well. Snakes have the same language as lizards. They have teeth. Some snakes are venomous. Snakes are predatory animals. They also shed their skin and their body coloration is protective. Among the snakes there are those that strangle the victim, wrapping themselves around in rings. This is a boa constrictor and a python.

There are miniature blind snakes. They can even live in a flower pot (Fig. 16).

Rice. 16. Blind snake ()

The rattlesnake is known for its rattle at the end of its tail. This is a kind of warning about the appearance of this snake (Fig. 17).

Rice. 17. Rattlesnake ()

In nature, there are even two-headed snakes (Fig. 18).

Rice. 18. Two-headed snake ()

There are completely harmless snakes - these are snakes (Fig. 19). In case of danger, they themselves can pretend to be dead.

But the common viper is a viviparous snake (Fig. 20).

Very dangerous and poisonous snakes are taipan (fig. 21) and tiger snake (fig. 22).

Rice. 22. Tiger snake ()

A cobra has a warning before an attack - a swollen hood (Fig. 23).

There are tree flying snakes. When in a tree, they jump straight down in search of prey if necessary.

There is another type of reptile - this turtles. There are about 200 species of them. The body of turtles is usually hidden under a powerful shell, their limbs and neck are keratinized, the shape of the head is pointed, the turtles have no teeth. Turtles have color vision. In case of danger, the turtle hides all the protruding parts of the body under the shell. Turtles can be herbivores and carnivores. In nature, there are land, sea and freshwater turtles. The largest leatherback turtle belongs to the marine ones (Fig. 24).

Rice. 24. Leatherback turtle ()

Green turtle meat is eaten by humans (Fig. 25).

Rice. 25. Green turtle ()

Sea turtles have flat limbs, they do not retract them into the shell. These reptiles are excellent swimmers.

Land turtles less mobile. Among them are centenarians. The sizes are very different. Very large elephant (Fig. 26), and small - spider turtle (Fig. 27).

Rice. 26. Elephant turtle ()

Rice. 27. Spider Turtle ()

The Central Asian turtle hisses like a snake (Fig. 28).

Rice. 28. Central Asian tortoise ()

There are also freshwater turtles - this is the mata-mata fringed turtle. Its appearance is very unusual (Fig. 29).

Rice. 29. Turtle mata-mata ()

The Chinese trionics belongs to soft-bodied turtles (Fig. 30).

Rice. 30. Chinese trionics ()

Caiman turtles are very biting and aggressive (Fig. 31).

Rice. 31. Cayman turtle ()

There are other representatives of reptiles - this is crocodiles. There are about 20 species in nature. Crocodiles are semi-aquatic animals, their skin is covered with shields and plates. They have an elongated, long body. Muscular tail and webbed limbs provide excellent swimming in the water. Crocodiles see and hear well. They have powerful jaws with sharp teeth. Crocodiles swallow their food whole, without chewing. The combed crocodile is considered the largest; it can even attack a person (Fig. 32). Its weight reaches over one ton. The Chinese alligator is a symbol of power in its homeland, because it looks like a dragon. In China, it is believed that meeting with a crocodile is good luck.

Caimans are orderlies of reservoirs.

The Ghanaian gharial has a very unusual appearance (Fig. 35). It has surprisingly narrow and long jaws that look like large tweezers. They help to catch the most agile fish.

Rice. 35. Ghanaian gavial ()

In nature, there is another order of reptiles - this beakheads. The most interesting thing is that it consists of only one representative, the tuatara, which is found only in New Zealand. Hatteria has a peculiar body shape. In appearance, the hatteria is more like a lizard, its head has a tetrahedral shape, the head and the whole body are covered with scales of various shapes. On the neck, back, tail stretches a comb of spikes. In addition to teeth, the tuatara has incisors, like rodents. The shape of the mouth is also unusual like a beak. The most interesting thing is that this reptile has three eyes. The third eye is located on the head and is covered with thin skin. Tuataria are the most cold-loving of all reptiles (Fig. 36).

Rice. 36. Hatteria ()

In the lesson, we were convinced that reptiles are amazing and interesting animals that rightfully occupy an important place in nature. . Consider the most interesting representatives of reptiles.

The largest snake is the Anaconda water boa, 11 m 43 cm.

The largest lizard is a monitor lizard from Komodo Island, up to 3 m in length, weighing up to 140 kg.

The largest crocodile is combed, up to 9 m in length, and its mass is approximately 1 ton.

The largest turtle in the sea is leathery, about 3 m, and its weight is 960 kg.

On land, the largest turtle is elephant, 2 m long, weighing up to 600 kg.

The most venomous snakes are taipan, black mamba, tiger snake, rattlesnake, sea snake.

The number of species of reptiles is decreasing, and people are also to blame. Very often a person, because of his fear, destroys and destroys these animals. It must be remembered that, like all living things, reptiles must be protected and protected.

The next lesson will cover the topic “Ancient reptiles and amphibians. Dinosaurs. On it, we will go on a long journey many millions of years ago and get acquainted with ancient reptiles and amphibians, the features of their structure and habitat. We will also learn about animals that became extinct many centuries ago - dinosaurs.

Bibliography

1. Samkova V.A., Romanova N.I. The world around 1. - M .: Russian word.
2. Pleshakov A.A., Novitskaya M.Yu. The world around 1. - M .: Education.
3. Gin A.A., Faer S.A., Andrzheevskaya I.Yu. The world around 1. - M .: VITA-PRESS.

1. Mirzhivotnih.ru ().
2. Filin.vn.ua ().
3. Festival of pedagogical ideas "Open Lesson" ().

Homework

1. Who are reptiles?
2. What are the characteristics of reptiles?
3. Name four orders of reptiles and describe each of them.
4. * Draw a picture on the topic: "Reptiles in our world."

Reptiles are an unusual class that lies between amphibians and mammals. Otherwise they are called reptiles. But not everyone knows who reptiles are.

Reptiles are vertebrates that resemble birds and mammals.

Let's take a closer look at this class.

Who are reptiles

Members of this class are cold-blooded creatures. Their body temperature is determined by the ambient temperature. But they have one feature, they can regulate their own temperature. The ancestors of reptiles are amphibians. In winter, reptiles usually sleep. And in hot weather they lead only a nocturnal lifestyle.

The skin of reptiles is tough and covered with scales.. Such skin is needed in order to protect the body from drying out. These animals breathe only through the lungs. Some representatives of this class have lungs of the same size, while others have one lung larger than the other. And this is the norm. The skeleton of reptiles is well developed. Everyone has ribs, but their number depends on the representative of this class.

Almost all species of this class have a language, but for someone it is short, and for someone it is very long. It is also the main sense organ. To protect themselves from enemies, these animals change color, some have a hard shell, and some are generally poisonous. These animals breed like birds, that is, they lay eggs.

The following animals belong to the class of reptiles:

• snakes;
• Lizards;
• Turtles;
• Dinosaurs.

reptile types

Reptiles or reptiles are divided into four orders:

Reptiles can be found anywhere, but most of them live in warm countries. Where it is always cold and there is little vegetation, these animals are very rare. Reptiles live everywhere. And in the water, and on the ground, and in the air. Let's take a closer look at the representatives of this class.

Turtles

Turtles are the most famous among reptiles. They can live both on land and in water. They can be seen not only in the zoo and in the wild, many keep them at home. These cute animals do not pose any danger to humans, they are harmless.

Turtles appeared about two hundred million years ago. These reptiles have a shell. He protects them from enemies. It consists of two parts: abdominal and dorsal. From above it is covered with horny tissue in the form of plates.

These animals come in different sizes.. There are giant tortoises that can reach 900 kilograms. And there are little turtles. Their mass does not exceed 125 grams, and the length of the shell is only ten centimeters.

Instead of teeth, this animal has a powerful beak. With it, she crushes food.

According to their habitat, turtles are divided into:

• Freshwater: painted or decorated, European marsh, red-eared, caiman;
• Marine: hawksbill turtle, leathery, green or soup;
• Ground;
• Land: elephant, Egyptian, Central Asian, leopard, Cape;

What do these animals eat?. Their food is completely dependent on their habitat. Land turtles feed on fruits, vegetables, tree branches, mushrooms and grass. And sometimes they can even eat worms and snails.

Water turtles feed on small fish, shrimps, squids, frogs, snails, mollusks, insects, bird eggs.

Land turtles who live at home eat cabbage, apples, tomatoes, beets, cucumbers, dandelions, chicken eggs. And domestic water turtles love to eat earthworms, boiled meat, bloodworms, insects, algae and lettuce.

The turtle is a long-liver. She will outlive any other representative of reptiles.

crocodiles

Crocodile

The crocodile is the only member of the archosaur subclass. Their body length is from two to seven meters. And the mass can reach more than 700 kilograms. The crocodile is a fairly fast animal in the water. Its speed can reach forty kilometers per hour.

The number of teeth in a crocodile ranges from 70 to 100. It depends on the type of crocodile. The teeth are long and sharp, about five centimeters.

These animals live only in warm countries with a humid climate: Africa, Japan, Australia, Bali, North and South America, Guatemala, the Philippine Islands.

Crocodile is a predator, so he eats fish, shellfish, birds, lizards, snakes, antelopes, deer, buffaloes, wild boars, dolphins, sharks, leopards, lions, hyenas. These animals can even eat a monkey and a porcupine, a kangaroo and a bunny. And there are times when crocodiles eat their own kind.

Crocodiles live for a long time - a hundred years.

Variety of crocodiles

Crocodiles are divided into three families: true crocodiles, gharials and alligators.

In its turn, Crocodiles of the present family are divided into the following types:

The alligator family is divided into:

• Mississippi - differ from other species in that it can calmly endure the cold, freezing its whole body into ice.
• Chinese - a rare and small species of alligators. Its length does not exceed two meters, and it weighs only about forty-five kilograms.
• Crocodile caiman - otherwise it is called a spectacled crocodile. This is due to the fact that on his face between the eyes there are growths that resemble glasses.
• The black caiman is a fairly large species of alligator. Its length reaches 5.5 meters, and it weighs more than 500 kilograms.

The gavial family is divided into:

• Gangetic gharial. The length of his body reaches six meters, and he weighs only about two hundred kilograms.
• gavial. The muzzle of this species is narrow and long. The body length is six meters, and the weight does not exceed 200 kilograms.

Tuatara

Most people think that tuatara is lizard. But this is an erroneous opinion. This reptile lived in the era of dinosaurs and forms a detachment of beakheads. This reptile has another name - tuatara.

They live only in New Zealand. In appearance, they resemble an iguana. Internally, the structure looks like a snake. They took something from turtles, and something from crocodiles.

She also has another feature - three eyes. The third eye is located on the back of the head. The length of the tuatara reaches more than fifty centimeters, and it weighs no more than one kilogram.

This amazing animal leads only a nocturnal lifestyle. The breath of the tuatara is slow. She can hold her breath for sixty minutes.

This reptile feeds on insects, snails, and worms. Life expectancy is quite long, about a hundred years.

lizards

Lizards belong to the class of reptiles.. Their diversity is very large - about six thousand species. All of them differ from each other in their size, color, habitat.

Lizards are very similar to newts, but they have many differences. One of the main differences is that the newt is an amphibious animal. An amphibious animal is different from a reptile.

Almost all lizards have a feature- This is the ability to drop your tail in case of emergency. Many lizards can change body color.

Lizards feed on insects: butterflies, snails, grasshoppers, spiders, worms. Large representatives feed on small animals, snakes and frogs.

Lizards are divided into six infraorders:

• Skin-shaped;
• Iguanas;
• Geckos;
• Fusiform;
• worm-like;
• monitor lizards

All these infraorders are divided into families. Skin-shaped are divided into:

iguanas divided into fourteen families. The most striking representative of this infraorder is the chameleon.

geckos divided into seven families. Of which an unusual lizard can be distinguished - this is a scale leg. The peculiarity of this reptile is that it has no legs.

Fusiform is divided into five families: earless monitor lizards, fusiform, legless lizards, monitor lizards, xenosaurs.

worm-like lizards are from the same family. These reptiles are similar to earthworms.

monitor lizards consist of several families. They are the largest lizards. For example, a Komodo dragon can weigh over ninety kilograms.

snakes

The snake is a cold-blooded animal, which belongs to the class of reptiles. The weight and size of snakes is different. Their length can reach nine meters, and weight more than one hundred kilograms.

Snakes are venomous and non-venomous. These reptiles are deaf. They navigate through language. It is he who collects information about the environment.

Snakes feed rodents, bird eggs, fish, and some even feed on their own kind. They only eat twice a year.

Snakes are oviparous. Someone lays ten eggs, and someone one hundred and twenty thousand eggs. Some representatives give birth to live cubs.

The variety of snakes is huge. There are more than three thousand species of them.

The most interesting representatives are the following:

Now you know what reptiles or reptiles are. And who are their representatives.

What is a reptile? This question is of interest to all students taking a biology course in their educational institutions. However, the question of what a reptile is can be asked not only by schoolchildren and students.

Young children are also interested in animal themes, especially crawling and jumping ones. Adults, observing the world around them, may also ask questions about what a reptile is and what are its features. This article will be devoted to this topic.

Definition

In short, reptiles are eukaryotic organisms of the chordate type. They include terrestrial vertebrates such as turtles, amphisbaes, crocodiles, lizards, beakheads, snakes, and the like.

According to rough estimates, the Reptile class includes about 9.5 thousand species. Almost eighty varieties of them live in our country.

What are the main signs of reptiles by which they can be distinguished from other representatives of the world fauna? Let's find out.

Epidermis

Yes, in order to understand the question of what a reptile is, it is necessary to study in detail its appearance, way of life and other features.

So, the skin. The epidermis of this class of animals is thickened and keratinized. As a result, scales are formed on the surface that overlap each other, like tiles on the roof of a residential building. Interestingly, several times a year (in almost all species) there is a complete or partial replacement of the horny cover, in other words, molting.

The skin of reptiles is hard and dry, it does not have mucous glands, but it has special secretory cells that produce odorous substances.

The inner layer of the dermis contains pigments, due to which some amphibians and reptiles are able to change their body color. This is especially true for the chameleon.

Skeleton

The class Reptiles has an axial skeleton, consisting of five sections of the spinal column: caudal, sacral, lumbar, trunk and cervical. The total number of vertebrae depends on the type of animal, usually fifty to eighty. However, in snakes their number varies between 140 and 435.

Interestingly, the two front cervical vertebrae of reptiles form one joint, which helps the head to stay upright and turn in different directions.

Most representatives of this class have a chest (however, snakes do not have it), as well as a pelvis attached to the sacral region. The tail vertebrae (from 15 to 40 pieces) are a group of gradually decreasing rod-shaped bones.

The skull of reptiles is ossified and rather strong. The front and hind limbs are equipped with claws.

Skeletal muscles

Class Reptiles has a muscular system, the fibers of which are adapted to work in conditions unusual for humans (without oxygen), which allows animals to move short distances in record time. However, after intense running, muscle fatigue quickly develops, provoked by the accumulation of lactic acid in the muscles.

nervous structure

The nervous system of amphibians and reptiles consists of two types of brain:

• Brain. Located inside the skull, twelve pairs of nerves diverge from it. It is subdivided into the anterior, intermediate, middle, medulla oblongata and cerebellum.
• Dorsal. From which the spinal nerves originate, forming the brachial and pelvic plexuses.

Opportunities

Like many chordates, amphibians and reptiles have six senses. First of all it is:

1. Vision. The eyes of reptiles are able to distinguish objects in the air. Thanks to the lacrimal glands, they are protected from drying out, and the nictitating membrane and eyelids perform other protective functions.
2. Smell. It is represented by choans (internal nasal openings), which allow animals to breathe freely when food is in the throat, and also help to find food buried in the ground at a depth of up to eight centimeters.
3. Taste. Represented by taste buds located in the pharynx and the inner part of the tongue.
4. Hearing. Although most reptiles have ears, hearing does not play a significant role in their life. Many perceive sound signals in a very small range (approximately from sixty to two hundred hertz).
5. Touch. This feeling is clearly expressed. Animals can recognize even a light touch on their shell or keratinized epidermis.
6. Thermal sensitivity is an important sensory organ of reptiles, located in the area of ​​​​a small depression between the eye and the nose of the animal.

Breath

The respiratory system of this class is represented by bag-shaped lungs, trachea and bronchi. Inhalation and exhalation are possible due to the process of expansion and contraction of the muscles located in the intercostal and abdominal zone.

Skin respiration is absent in these animals, with the exception of some subfamilies of turtles and snakes.

Circulatory system

Circulation is one of the main features of reptiles. Most often it is represented by a three-chambered heart, veins, arteries and aorta. It is noteworthy that the blood circulation consists of systems that are practically independent of each other, which, however, are combined in the dorsal aorta.

Digestion

This important system is represented by numerous organs: strong teeth, bony palate, muscular forked tongue, narrow esophagus, thick-walled stomach, pancreas, liver, and so on.

The salivary glands of animals possess digestive enzymes.

genitourinary system

Primarily, the urinary system includes the kidneys, ureter, and bladder.

With regard to the reproductive system, it should be noted that reptiles are animals of different sexes. Males have two testes, a wolf duct, and a seminal vesicle.

In females, ovaries and Müllerian ducts are observed.

So, having analyzed the structure of reptiles, we smoothly moved on to their way of life. Let's start with reproduction.

Reproduction of offspring

The reproduction of reptiles includes internal fertilization, the result of which is the deposition of eggs. Most often, animals lay their eggs in nests or other secluded places.

In some cases, the reproduction of reptiles can be the gestation of eggs by the female (in a special internal area of ​​\u200b\u200bthe oviduct) until the cubs hatch. Most often, some individual species of vipers and lizards breed in this way.

For many representatives of this class, an instinctive desire to take care of offspring is inherent, although there are cases of eating cubs by females. Most often this happens with crocodiles.

What else can be said about the lifestyle of reptiles?

Nutrition

Representatives of this class are carnivores, that is, those who eat meat. And yet, sometimes there are species of reptiles that consume mixed or even herbal food.

Way of movement and communication

Most often, animals move with the help of four limbs, dragging their stomach along the ground.

The head apparatus of reptiles is poorly developed, so they very rarely give a voice. In exceptional cases (fear, pain, rage, mating season) some sounds can be made.

Types of reptiles

Representatives of this class, found in various parts of the world, are divided into four groups:

1. Turtles. Includes a little more than three hundred species.
2. Crocodiles. There are 25 varieties.
3. Scaly. This includes almost 5.5 thousand lizards and snakes.
4. Getteria (otherwise - tuatara).

Let's talk about them in more detail.

Reptiles. List

Turtles. This detachment is divided into sea and land. The latter include land and freshwater.

The distinctive and most recognizable feature of these animals is the shell that protects them from enemies. It can withstand a weight two hundred times the weight of the individual itself.

Some turtles, such as elephant turtles, can reach one and a half meters in length, while their body weight can be four hundred kilograms. The smallest species (these primarily include the Cape speckled, living in South Africa) can barely reach ten centimeters. Accordingly, the body weight of such turtles is also small - about two hundred grams.

Turtles live longer than all vertebrates. Their life expectancy can reach two hundred years or more.

crocodiles. They have a large and dense lizard-like body, very thick skin and a strong tail. They can swim well and move a little on land. Most often, animals are found in regions with a tropical climate. They can reach two to five meters in length. The bite of a crocodile is very strong and painful.

snakes. Their body length can vary from ten centimeters to seven meters. Many snakes are venomous (capable of killing even humans). Others can be dangerous because they use their ability to strangle (or suffocate) their prey for hunting purposes.

The largest snakes are the reticulated python and the anaconda.

It is noteworthy that snakes, unlike other reptiles, do not have paired limbs, eyelids, and an external auditory apparatus.

Chameleons. These unique animals are able to change the color of the epidermis for camouflage or protective purposes. They live in trees and feed mainly on insects.

iguanas. These are lizards, distinguished by spiky ridges located on the tail and along the back. They prefer to live in trees, eat greens and fruits.

monitor lizards. Very similar to dinosaurs. The length of animals can vary from twenty centimeters to three meters. The weight of monitor lizards depends entirely on the length. Sometimes body weight can reach one and a half tons.

Animals have a tenacious grip and a powerful tail. Their tongue is forked, it is the organ of smell. They can live in Africa, Asia and Australia, live among desert thickets or near water bodies.

geckos. Interesting animals that can stick to any, even the smoothest surface. Most often they lead a nocturnal lifestyle. They can call each other with a variety of sounds.

Finally

The species of reptiles listed above prove how rich and diverse the world of wildlife is. The class of reptiles includes many species and families, diverse in appearance, way of life and other properties.

And yet they are united by common features inherent in one class. First of all, it is a thick scaly skin, the respiratory system, and also the circulatory and digestive systems.

Many reptiles are carnivores. They reproduce bisexually, laying their eggs in a variety of places.

Do people use reptiles for their own purposes? Yes, but not all. For example, the skin of crocodiles, large lizards and snakes can be used to make a variety of products or items for use. Meat or eggs of some reptiles can be eaten. Snake venom is often used in pharmacology and cosmetology for the manufacture of ointments, creams and other products.

Reptiles are true land animals that breed on land. They live in countries with a hot climate, and as they move away from the tropics, their number noticeably decreases. The limiting factor in their distribution is temperature, as these cold-blooded animals are active only in warm weather, in cold and hot weather they burrow, hide in shelters, or fall into a torpor.

In biocenoses, the number of reptiles is small and therefore their role is hardly noticeable, especially since they are not always active.

Reptiles feed on animal food: lizards - insects, molluscs, amphibians, snakes eat many rodents, insects, but at the same time they pose a danger to domestic animals and humans. Herbivorous land turtles cause damage to gardens and orchards, aquatic turtles feed on fish and invertebrates.

The meat of many reptiles is used as food (snakes, turtles, large lizards). Crocodiles, turtles and snakes are exterminated for the sake of the skin and horny shell, and therefore the number of these ancient animals has been greatly reduced. There are crocodile farms in the USA and Cuba.

The Red Book of the USSR includes 35 species of reptiles.

About 6300 species of reptiles are known, which are much more widespread on the globe than amphibians. Reptiles live mainly on land. Warm and moderately humid regions are most favorable for them, many species live in deserts and semi-deserts, but only a very few penetrate into high latitudes.

Reptiles (Reptilia) are the first terrestrial vertebrates, but there are some species that live in the water. These are secondary aquatic reptiles, i.e. their ancestors moved from a terrestrial way of life to an aquatic one. Of the reptiles, venomous snakes are of medical interest.

Reptiles, together with birds and mammals, make up the superclass of higher vertebrates - amniotes. All amniotes are true terrestrial vertebrates. Thanks to the embryonic membranes that have appeared, they are not associated with water in their development, and as a result of the progressive development of the lungs, adult forms can live on land in any conditions.

Reptile eggs are large, rich in yolk and protein, covered with a dense parchment-like shell, develop on land or in the mother's oviducts. The water larva is absent. A young animal hatched from an egg differs from adults only in size.

Class characteristic

Reptiles are included in the main trunk of the evolution of vertebrates, since they are the ancestors of birds and mammals. Reptiles appeared at the end of the Carboniferous period, approximately 200 million years BC, when the climate became dry, and in some places even hot. This created favorable conditions for the development of reptiles, which turned out to be more adapted to living on land than amphibians.

A number of features contributed to the advantage of reptiles in competition with amphibians and their biological progress. These should include:

• a shell around the embryo (including the amnion) and a strong shell (shell) around the egg, protecting it from drying out and damage, which made it possible to reproduce and develop on land;
• further development of the five-fingered limb;
• improvement of the structure of the circulatory system;
• progressive development of the respiratory system;
• appearance of the cerebral cortex.

The development of horny scales on the surface of the body, which protected against adverse environmental influences, primarily from the drying effect of air, was also important.

reptile body divided into head, neck, torso, tail and limbs (absent in snakes). Dry skin is covered with horny scales and scutes.

Skeleton. The spinal column is divided into five sections: cervical, thoracic, lumbar, sacral and caudal. Skull bony, occipital condyle one. In the cervical spine there is an atlas and an epistrophy, due to which the head of the reptiles is very mobile. Limbs end with 5 fingers with claws.

musculature. It is much better developed than in amphibians.

Digestive system. The mouth leads to the oral cavity, equipped with a tongue and teeth, but the teeth are still primitive, of the same type, they serve only to capture and hold prey. The digestive tract consists of the esophagus, stomach and intestines. On the border of the large and small intestines is the rudiment of the caecum. The intestine ends with a cloaca. Developed digestive glands (pancreas and liver).

Respiratory system. In reptiles, the respiratory tract is differentiated. The long trachea branches into two bronchi. The bronchi enter the lungs, which look like cellular thin-walled bags with a large number of internal partitions. The increase in the respiratory surface of the lungs in reptiles is associated with the absence of skin respiration. Breathing is only lung. The breathing mechanism of the suction type (breathing occurs by changing the volume of the chest), more advanced than that of amphibians. Conductive airways (larynx, trachea, bronchi) are developed.

excretory system. Represented by secondary kidneys and ureters that flow into the cloaca. It also opens the bladder.

Circulatory system. There are two circles of blood circulation, but they are not completely separated from each other, due to which the blood is partially mixed. The heart is three-chambered (in crocodiles, the heart is four-chambered), but consists of two atria and one ventricle, the ventricle is divided by an incomplete septum. The large and small circles of blood circulation are not completely separated, but the venous and arterial flows are more strongly separated, so the body of reptiles is supplied with more oxygenated blood. Separation of flows occurs due to the septum at the time of contraction of the heart. When the ventricle contracts, its incomplete septum, attached to the abdominal wall, reaches the dorsal wall and separates the right and left halves. The right half of the ventricle is venous; the pulmonary artery departs from it, the left aortic arch begins above the septum, carrying mixed blood: the left part of the ventricle is arterial: the right aortic arch originates from it. Converging under the spine, they merge into an unpaired dorsal aorta.

The right atrium receives venous blood from all organs of the body, and the left atrium receives arterial blood from the lungs. From the left half of the ventricle, arterial blood enters the vessels of the brain and anterior part of the body, from the right half of the venous blood goes to the pulmonary artery and then to the lungs. Mixed blood from both halves of the ventricle enters the trunk region.

Endocrine system. Reptiles have all the endocrine glands typical of higher vertebrates: the pituitary, adrenals, thyroid, etc.

Nervous system. The brain of reptiles differs from the brain of amphibians in the large development of the hemispheres. The medulla oblongata forms a sharp bend, characteristic of all amniotes. The parietal organ in some reptiles functions as a third eye. The rudiment of the cerebral cortex appears for the first time. There are 12 pairs of cranial nerves that emerge from the brain.

The sense organs are more complex. The lens in the eyes can not only mix, but also change its curvature. In lizards, the eyelids are movable; in snakes, the transparent eyelids are fused. In the organs of smell, part of the nasopharyngeal passage is divided into olfactory and respiratory sections. The internal nostrils open closer to the pharynx, so reptiles can breathe freely when they have food in their mouths.

reproduction. Reptiles have separate sexes. Sexual dimorphism is pronounced. Sex glands are paired. Like all amniotes, reptiles are characterized by internal insemination. Some of them are oviparous, others are ovoviviparous (that is, a cub immediately emerges from a laid egg). Body temperature is not constant and depends on the ambient temperature.

Systematics. Modern reptiles are divided into four subclasses:

1. lizards (Prosauria). The first lizards are represented by a single species - the hatteria (Sphenodon punctatus), which is one of the most primitive reptiles. The tuatara lives on the islands of New Zealand.
2. scaly (Squamata). This is the only relatively large group of reptiles (about 4000 species). The scaly ones are
   • lizards. Most species of lizards are found in the tropics. This order includes agamas, poisonous lizards, monitor lizards, real lizards, etc. Lizards are characterized by well-developed five-fingered limbs, movable eyelids and eardrums [show] .

     The structure and reproduction of the lizard

     quick lizard. The body is 15-20 cm long on the outside covered with dry skin with horny scales that form quadrangular scutes on the abdomen. The hard cover interferes with the uniform growth of the animal, the change of the horny cover occurs by molting. In this case, the animal sheds the upper stratum corneum of the scales and forms a new one. The lizard molts four to five times during the summer. At the ends of the fingers, the horny cover forms claws. The lizard lives mainly in dry sunny places in the steppes, sparse forests, shrubs, gardens, on the slopes of hills, railway and highway embankments. Lizards live in pairs in minks, where they hibernate. They feed on insects, spiders, mollusks, worms, eat many pests of agricultural crops.

     In May-June, the female lays 6 to 16 eggs in a shallow hole or burrow. The eggs are covered with a soft fibrous leathery shell that protects them from drying out. The eggs have a lot of yolk, the protein shell is poorly developed. All development of the embryo takes place in the egg; after 50-60 days, a young lizard hatches.

     In our latitudes, lizards are often found: agile, viviparous and green. All of them belong to the family of real lizards of the scaly order. The agama family belongs to the same order (steppe agama and roundheads - inhabitants of the deserts and semi-deserts of Kazakhstan and Central Asia). The scaly ones also include chameleons that live in the forests of Africa, Madagascar, India; one species lives in southern Spain.

   • chameleons
   • snakes [show]

     The structure of snakes

     Snakes also belong to the scaly order. These are legless reptiles (some retain only the rudiments of the pelvis and hind limbs), adapted to crawling on their belly. Their neck is not expressed, the body is divided into head, trunk and tail. The spine, which has up to 400 vertebrae, has great flexibility due to additional joints. It is not divided into departments; almost every vertebra bears a pair of ribs. In this case, the chest is not closed; the sternum of the girdle and limbs are atrophied. Only a few snakes have preserved a vestige of the pelvis.

     The bones of the facial part of the skull are movably connected, the right and left parts of the lower jaw are connected by very well stretchable elastic ligaments, just as the lower jaw is suspended from the skull by stretchable ligaments. Therefore, snakes can swallow large prey, even larger than a snake's head. Many snakes have two sharp, thin, poisonous teeth bent back, sitting on the upper jaws; they serve to bite, detain prey and push it into the esophagus. Poisonous snakes have a longitudinal groove or duct in the tooth, through which the poison flows into the wound when bitten. The poison is produced in altered salivary glands.

     Some snakes have developed special organs of thermal sense - thermoreceptors and thermolocators, which allows them to find warm-blooded animals in the dark and in burrows. The tympanic cavity and membrane are atrophied. Eyes without eyelids, hidden under transparent skin. The skin of the snake becomes keratinized from the surface and is periodically shed, i.e., molting occurs.

     Previously, up to 20-30% of victims died from their bites. Due to the use of special therapeutic sera, mortality has decreased to 1-2%.

3. Crocodiles (Crocodilia) are the most highly organized reptiles. They are adapted to an aquatic lifestyle, in connection with which they have swimming membranes between the fingers, valves that close the ears and nostrils, and a palatal curtain that closes the pharynx. Crocodiles live in fresh waters, come to land to sleep and lay eggs.
4. turtles (Chelonia). Turtles are covered above and below with a dense shell with horny shields. Their chest is motionless, so the limbs take part in the act of breathing. When they are drawn in, the air leaves the lungs, when they are pulled out, it enters again. Several species of turtles live in the USSR. Some species, including the Turkestan tortoise, are eaten.

The value of reptiles

Anti-snake sera are currently used for therapeutic purposes. The process of making them is as follows: horses are successively injected with small, but ever-increasing doses of snake venom. After the horse is sufficiently well immunized, blood is taken from it and a therapeutic serum is prepared. Recently, snake venom has been used for medicinal purposes. It is used for various bleeding as a hemostatic agent. It turned out that with hemophilia, it can increase blood clotting. The drug from snake venom - vipratox - reduces pain in rheumatism and neuralgia. To obtain snake venom and to study the biology of snakes, they are kept in special nurseries. Several serpentaries operate in Central Asia.

Over 2,000 species of snakes are non-venomous, many of them feed on harmful rodents and bring significant benefits to the national economy. Of the non-venomous snakes, snakes, copperheads, snakes, and steppe boas are common. Water snakes sometimes eat juvenile fish in pond farms.

Meat, eggs and tortoise shells are very valuable, they are export items. The meat of monitor lizards, snakes, and some crocodiles is used as food. The valuable skin of crocodiles and monitor lizards is used for the manufacture of haberdashery and other products. Crocodile breeding farms have been set up in Cuba, the United States and other countries.