How many birds are in the picture. Class Birds (Aves). External structure of a bird

Task 1. "External structure"

What are the senses on the bird's head?
What departments are distinguished in the body of a bird?
What features are typical for poultry skin?
What are the featherless areas of skin called?

Task 2. "Plumage"

Consider the drawing and answer the questions:

What is indicated in the figure under the numbers 1 - 8?
What three types of feathers are distinguished in birds?
What types of contour feathers do birds have?
How often do birds shed?

Task 3. "Skeleton of Birds"

Consider the drawing and answer the questions:

What is indicated in the figure by numbers 1 - 21?
What are the characteristics of bird bones?
What departments are distinguished in the spine?
What parts of the spine have grown together? Why?
What is the peculiarity of the sternum of flying birds?
What kind of pelvis is typical for birds? In connection with what?
What bones form the shoulder girdle?
How is the buckle formed?
What is the tarsus formed by?

Task 4. "Internal structure of birds"

Consider the drawing and answer the questions:

What is indicated in the figure by the numbers 1 - 16?
What is characteristic of the esophagus of birds of prey, chicken and pigeons?
What is typical for the stomach of birds?
What ducts of glands open into the initial section of the small intestine?
What is on the border of the small and large intestines?
Where are the vocal cords of birds located?
What are the lungs of birds?

Task 5. "Double breathing
birds "

Consider the drawing and answer the questions:

Where does gas exchange take place in the lungs of birds?
In which direction does the air travel through the lungs of birds when they inhale? When you exhale?
How many times is the volume of air sacs greater than the volume of the lungs?
Does gas exchange take place in the air sacs?
Explain the drawing.

Task 6. "The circulatory system of birds"

Consider the drawing and answer the questions:

What is indicated in the figure by the numbers 1 - 8?
In which half of the heart is venous blood?
From which chamber of the heart does the pulmonary circulation begin?
Through which vessel does blood move from the heart to the lungs?
What veins do arterial blood flow through?
From which chamber of the heart does the systemic circulation begin?
What is the aortic arch in birds?

Task 7. "The brain of birds"

What is indicated in the figure by numbers 1 - 5?
How many pairs of cranial nerves do anamnias (fish, amphibians) and amniotes (birds) have?

Task 8. "Organ systems of birds"

** Test 1. Features of the digestive system of birds.

Some species of modern birds have teeth on their jaws.
In pigeons, birds of prey, the esophagus expands into a crop.
From the esophagus, food first enters the muscular, and then into the glandular stomach.
The ducts of two large digestive glands - the pancreas and the liver - open into the stomach.
The ducts of the liver and pancreas open into the first section of the small intestine.
A well-developed cecum is located at the border of the small and large intestines.
The large intestine is short and opens into the cloaca.
The digestive, excretory and reproductive systems open in the cloaca.

** Test 2. Features of the respiratory system of birds.

At the top of the trachea is the singing larynx.
The singing larynx is located at the site of the division of the trachea into bronchi.
The enrichment of blood with oxygen occurs in the capillaries that encircle the alveoli.
The enrichment of blood with oxygen occurs in the capillaries that encircle the parabronchus.
Birds have double breathing: gas exchange occurs both during inhalation and exhalation.
Air travels through the lungs in one direction as you inhale and exhale - from the back air sacs through the lungs to the front.
When you inhale, the air fills the lungs, when you exhale, it leaves the lungs, that is, it moves through the lungs in two directions.
The volume of the air sacs is 10 times the volume of the lungs.
Air bags keep the bird from overheating during flight.

** Test 3. Features of the circulatory system of birds?

The heart is four-chambered.
There is arterial blood in the right half of the heart.
The small (pulmonary) circle of blood circulation ends in the right atrium.
The systemic circulation ends in the right atrium.
The right aortic arch and pulmonary artery depart from the ventricle.
The left aortic arch and pulmonary artery depart from the ventricle.
Arterial blood flows through the pulmonary artery.
In birds, the heart works very intensively, the heart rate in small birds can reach 1000 times per minute.
Birds have a very fast metabolism, they have a constant body temperature and are warm-blooded animals.

** Test 4. The nervous and excretory systems of birds are characterized by:

Complicated bird behavior is associated with good forebrain development.
Good vision is provided by the diencephalon.
A well-developed cerebellum is responsible for the coordination of movements.
Most birds have black and white vision.
Most birds have color vision.
The sense of smell in birds is poorly developed.
The end product of metabolism in birds is ammonia.
The end product of metabolism in birds is uric acid.
The end product of metabolism in birds is urea.
The bladder in birds is absent due to flight.
The bladder in birds is small and opens into the cloaca.

Task 9. "Reproductive and excretory systems"

Consider the drawing and answer the questions:

A - male genitourinary system; B - females

What is indicated in the figure by numbers 1 - 7?
What feature is characteristic of the excretory system of birds?
In which part of the oviduct does the fertilization of the egg take place?
Which ovary in birds is usually reduced?
What membranes does the ovum cover during its passage through the oviduct?

Task 10. "The construction of the egg and the development of the embryo"

Consider the drawing and answer the questions:

What is indicated in the figure by numbers 1 - 11?
What are the names of the membranes that cover the egg, egg membranes?
What are chalazes?
Why is the germ disc always on top?
What is the name of the embryo membrane that surrounds the developing embryo and is filled with fluid in which the embryo floats?
Which membrane is the outgrowth of the hind gut, accumulates metabolic products, blood vessels grow in it and it becomes an important organ of gas exchange?
What is the name of the outermost embryo membrane adjacent to the shell?

Task 11. "Embryo and egg membranes"

Sketch and fill in the table:

Task 12. "Chicks of the same age"

Consider the drawing and answer the questions:

What type of development does the chicks shown in the picture have?
What features are typical for the chicks shown in Figure 1?
What features are typical for the chicks shown in Figure 2?
What determines the size of the clutch of chicks and brood birds?

Task 13. "Reproduction and development of birds"

Write down the test numbers, against each - the correct answer options

** Test 1. The reproductive system of male birds has the following features:

The sex glands are two testicles in a body cavity.
The vas deferens open with a separate genital opening on the surface of the body.
The vas deferens open into the cloaca.
By the time of reproduction, the size of the testes increases a thousand times.

** Test 2. The reproductive system of female birds has the following features:

The sex glands are two ovaries in a body cavity.
In birds, only the left ovary is developed, the right one is reduced.
In birds, only the right ovary is developed, the left is reduced.
Fertilization of the egg takes place in the upper part of the oviduct.
Fertilization of the egg takes place in the cloaca.
In the oviducts, the egg cell is covered by the embryonic and egg membranes.
In the oviducts, the egg is covered only by the egg membranes.

** Test 3. Egg membranes include:

Amnion. 5. Shell.
Serosa (chorion). 6. Supershell.
Protein. 7. Allantois.
Two fibrous.

Test 4. Which weighs more - the egg before hatching, or the chick that hatched from this egg and weighed together with the shell immediately after hatching?

The weight will be the same.
The egg will be heavier.
The shell chicken will be heavier.

** Test 5. Indicate which birds from the above list belong to brood (a) and chicks, or nest (b):

Chickens. 5. Parrots.
Ducks. 6. Woodpeckers.
Geese. 7. Songbirds.
Doves. 8. Swans.

Z

Adania 14. "Imprint of Archeopteryx"

Consider the drawing and answer the questions:

What ancient reptiles are considered the ancestors of birds?
When did Archeopteryx live on Earth?
What are some signs of Archeopteryx suggesting it couldn't have been a good flyer?

Task 15. "Class Birds"

Write down the question numbers and answer in one sentence:

What features of the external structure allowed the birds to master the air habitat?
How many species of modern birds are known to science?
How are the fans of the contour feathers of birds formed?
What gland is well developed in birds?
What departments does the skeleton of birds consist of?
Features of skeletal bones associated with flight?
Which parts of the bird's spine have grown together?
What is the forelimb belt represented?
What are the bones of the forelimb?
What are the bones of the hind limb?
What muscles lift the wing? Lowering the wing?
What two stomachs do granivorous birds have?
In what direction does the air travel through the lungs of birds during inhalation and exhalation?
What blood is in the right side of the heart?
What is the aortic arch in birds?
What parts of the brain are better developed in birds compared to reptiles?
What reflexes are called conditioned?
What are the buds of birds?
What is the main protein metabolism product excreted in birds?
What is characteristic of the reproductive system of female birds?
What egg membranes are distinguished in an egg?
What embryonic membranes are formed during the development of a bird embryo?
Give two examples each of brood and nesting birds.
Give two examples each of sedentary, nomadic, and migratory birds.
What is the name of the largest modern bird? Her weight and height?
Which ancient reptiles share many similarities with birds and are considered the ancestors of birds?
What features are characteristic of the skeletal and jaw bones of Archeopteryx?
When did the real birds appear?

Task 16. "The most important terms and concepts of the topic"

Define terms or expand concepts (in one sentence, highlighting the most important features):

1. Pterilia, apterias. 2. Tarsus. 3. Buckle. 4. Keel. 5. Double breathing. 6. Bronchioles of the parabronchus. 7. Air bags.

Answers:

Exercise 1. 1.1 - head; 2 - torso; 3 - tail; 4 - wings; 5 - tarsus of the legs; 6 - toes; 7 - beak; 8 - mandible. 2. Organs of sight, hearing, smell, taste and touch. 3. Head, torso, tail, limbs. 4. Thin, dry, devoid of glands (with a single coccygeal gland). 5. Pharmacies.

Task 2. 1.1 - point; 2 - feather shaft; 3 - fan; 4 - barbs of the 1st order; 5 - barbs of the 2nd order; 6 - hooks; 7 - contour cover feather; 8 - down feather; 9 - down; 10 pterilia; 11 - pharmacies; 12 - primary flight feathers; 13 - secondary flight feathers. 2. Contoured, down and down. 3. Integumentary; primary-, secondary-, tertiary flight feathers and tail feathers. 4. Once or twice a year.

Task 3. 1.1 - mandible; 2 - beak; 3 - cerebral section of the skull; 4 - cervical spine; 5 - clavicle; 6 - crow bones (coracoids); 7 - scapula; 8 - humerus; 9 - forearm bones; 10 - buckle; 11 - phalanges of the fingers; 12 - ribs; 13 - sternum; 14 - keel; 15 - pelvic bones fused with a complex sacrum; 16 - caudal vertebrae; 17 - coccygeal bone; 18 - femur; 19 - shin bones; 20 - tarsus; 21 - phalanges of the fingers. 2. Lightweight, pneumatic, with cavities inside. 3. Cervical, thoracic, lumbar, sacral, caudal. 4. The thoracic vertebrae fused with a complex sacrum (lumbar, 2 sacral and part of the caudal vertebrae fused and formed a complex sacrum), due to the support of birds only on the hind limbs. The last caudal vertebrae are fused into the coccygeal bone. 5. Formed a keel. 6. Open, pubic bones do not grow together, due to the large size of eggs covered with a hard shell. 7. Paired shoulder blades, clavicle, crow bones (coracoids). 8. Fused bones of the wrist and some bones of the metacarpus. 9. Part of the bones of the tarsus and all bones of the metatarsus are fused.

Task 4. 1.1 - trachea; 2 - bronchi; 3 - lungs; 4 - heart; 5 - glandular stomach; 6 - gizzard; 7 - liver; 8 - spleen; 9 - small intestine; 10 - pancreas; 11 - kidneys; 12 - large intestine; 13 - testis; 14 - seed tube; 15 - cesspool; 16 - cloacal opening. 2. The esophagus has a goiter. 3. There is a glandular stomach, where enzymes act on food, and a muscular stomach, where food is ground. 4. Liver and pancreas. 5. Blind processes. 6. In the lower larynx. 7. Dense spongy bodies.

Task 5. 1. In the walls of the tertiary bronchi (parabronchi). 2. Both during inhalation and exhalation - in the same direction, from the posterior pulmonary sacs to the anterior ones. 3. 10 times. 4. No.

Task 6. 1.1 - right atrium; 2 - the right ventricle; 3 - left atrium; 4 - left ventricle; 5 - right aortic arch; 6 - veins of a large circle (hollow veins); 7 - pulmonary artery; 8 - pulmonary veins. 2. On the right. 3. From the right ventricle. 4. On the pulmonary artery. 5. By the pulmonary. 6. From the left ventricle. 7. Right.

Task 7. 1.1 - forebrain; 2 - midbrain; 3 - cerebellum; 4 - diencephalon; 5 - medulla oblongata. 2. Anamnias - 10 pairs, amniotes - 12 pairs.

Task 8. ** Test 1: 2, 5, 7, 8. ** Test 2: 2, 4, 5, 6, 8, 9. ** Test3: 1, 4, 5, 8, 9. ** Test 4: 1, 3, 5, 6, 8, 10.

Task 9. 1.1 - testes; 2 - vas deferens; 3 - kidneys; 4 - cloaca; 5 - ovary; 6 - oviduct; 7 - reduced right ovary (rudiment). 2. There is no bladder, it opens into the cloaca. 3. In the part where the oviduct funnel is located. 4. Right. 5. Squirrel, shell, shell.

Task 10. 1.1 - shell; 2 - shell shells; 3 - air chamber; 4 - protein; 5 - cords (chalazes) 6 - yolk; 7 - embryonic disc; 8 - embryo; 9 - amniotic fluid under the amniotic membrane; 10 - allantois; 11 - serosa. 2. Protein, shell, shell, shell. 3. Cords holding the yolk suspended. 4. The lower part of the yolk is heavier. 5. Amnion. 6. Allantois. 7. Serosa.

Task 11.

Shells

Functions, features:

Egg shells:

Protein

Two fibrous, shell, supershell shell

Embryonic membranes:

Allantois

Serosa (chorion)

Protective function, source of water and nutrients for the developing embryo.

Protection against mechanical damage, gas exchange (there are many pores in the shell), a source of minerals for the formation of the skeleton, protection against the penetration of microorganisms. The air cavity is a reservoir containing air for the chick to breathe as it leaves the egg.

The membrane that surrounds the embryo. Between the embryo and the amniotic membrane is the amniotic fluid in which the developing embryo is located. Performs protective functions.

The outgrowth of the hind gut, into which metabolic products enter. It gradually grows and adheres to the shell. Blood vessels develop in it, and it performs the function of gas exchange.

Outer germinal membrane.

Task 12. 1.1 - brood; 2 - chick. 2. The chicks of brood birds follow their parents in a few hours and are able to feed on their own. 3. Chicks hatch blind and helpless, need feeding, heating and protection for a long time. 4. For chicks, the size of the clutch is determined by the ability to feed the chicks, for broodlings - by the possibility of incubating the clutch.

Task 13. ** Test 1: 1 - yes; 2 - no; 3 - yes; 4 - yes. ** Test 2: 1 - no; 2 - yes; 3 - no; 4 - yes; 5 - no; 6 - no; 7 - yes. ** Test 3: 1 – 3, 4, 5, 6. Test 4: 2 (during incubation during the respiration of the embryo, part of the organic matter was oxidized). ** Test 5: 1 - a; 2 - a; 3 - a; 4 - b; 5 B; 6 - b; 7 - b; 8 - a.

Task 14. 1. Tecodonts, who lived 200 million years ago. 2.150 million years ago, in the Mesozoic era. 3. At the end of the Mesozoic era, 200 - 150 million years ago. 4. Absence of keel, fingers on the wings, bones are not pneumatic.

Task 15. 1. Wings, plumage. 2. 8 600 species. 3. Barbs of the first and second order, linked by hooks. 4. Coccygeal. 5. Skeleton of the head, skeleton of the trunk, limbs and their belts. 6. Lightness, pneumatic bones. 7. Thoracic, lumbar, sacral and first caudal vertebrae. 8. Paired shoulder blades, collarbones, crow bones and unpaired sternum. 9. The humerus, forearm bones, buckle and phalanges of the fingers. 10. Femur, shin bones, tarsus and phalanges of four fingers. 11. Raise - subclavian, lower - large chest. 12. Glandular and muscular. 13. From the back air sacs through the lungs to the front. 14. Venous. 15. Right. 16. Forebrain, middle and cerebellum. 17. Which are formed during life in response to external stimuli. 18. Secondary (pelvic, metanephros). 19. Uric acid. 20. Reduction of the right ovary. 21. White, two fibrous, shell, supra-shell. 22. Amnion, allantois, chorion. 23. Brood ducklings, chickens; chicks - pigeons, parrot chicks. 24. Sedentary - magpies, pigeons; nomadic - waxwings, bullfinches; migratory - swifts, swallows. 25. African ostrich, up to 3 m., 90 kg. 26. Tecodonts. 27. Bones are not pneumatic, on the jaws there are teeth. 28.200-150 million years ago.

Task 16. 1. Feathered and non-feathered areas of the skin. 2. Distal bones of the tarsus fused into one bone with the bones of the metatarsus. 3. Distal bones of the wrist fused into two long bones with the bones of the metacarpus. 4. Outgrowth of the sternum. 5. Double gas exchange during inhalation and exhalation, as during inhalation and exhalation, air flows through the lungs in the same direction. 6. Thin-walled tubes, braided with capillaries, in which gas exchange takes place. 7. Outgrowths of the bronchi located between the internal organs of birds, and their processes are located under the skin, between the muscles and in the cavities of the bones.

152. Draw a diagram of the external structure of the bird, sign the main parts of the body. What features of the external structure of a bird are associated with its ability to fly?

Streamlined body shape
The presence of wings
Feather cover
Small head, long neck, trunk and limbs are more compact

153. Consider the drawing. Write the names of the numbered portions of the pen.

1.fan
2.stem (barrel)
3.chin

154. Study the table “Class Birds. The structure of a dove ". Consider the drawing. Write the names of the bones of the bird's skeleton, indicated by numbers.

1.skull
2.brush
3.forearm
4.shoulder
5.coccygeal bone
6.thigh
7.shin
8.gun
9.fingers
10.sternum with keel
11. cervical spine

155. Indicate the features of the skeleton associated with the fitness of birds to fly.
The skeleton is characterized by strength and lightness. The tubular bones are hollow. Flat bones (skull, sacrum, pelvis) are very thin and grow together. The jaws have no teeth.
In the spinal column system there is a complex sacrum formed by the fusion of the last thoracic vertebrae, the lumbar region, the sacral itself and part of the caudal. The fused last caudal vertebrae form the coccygeal bone.
All the bones of the pelvis grow together and grow to the complex sacrum.
The shoulder girdle is highly developed and consists of powerful caracoid bones, shoulder blades and fused clavicles.
The forelimbs retain only three digits, and only the second toe has two phalanges. All bones of the metacarpus and wrist are fused into one complex bone, to which the flight feathers are attached.
The hind limbs often have four toes, sometimes three or two. There is a complex tarsus bone.
The sternum is large and, in most species, bears a sharp keel to which powerful pectoral muscles attach. The ribs of birds are flattened, the chest is strong and inactive.

156. Consider the drawing. Use colored pencils to color in the bird's circulatory system. Sign parts of it. Use arrows to indicate the movement of arterial and venous blood.

157. Fill in the table.

Bird organ systems.

158. Consider the drawing. Sign the names of the sections of the bird's brain.

159. Describe the process of double breathing of a bird.
When birds inhale, the volume of the body cavity increases and the air sacs expand, sucking in air. In this case, air from the lungs is sucked into the front air sacs, and air from the external environment through the trachea, bronchi goes into the lungs and into the rear air sacs. When you exhale, the volume of the body cavity decreases and, under the pressure of internal organs, air is squeezed out of the air sacs. The air containing a lot of oxygen from the rear air sacs is forced into the lungs, and the air from the front bags, which already contains little oxygen, but a lot of carbon dioxide, is pushed into the trachea and is expelled. Thus, oxygen-saturated air practically continuously, both during inhalation and exhalation, passes through the lungs, enriching the blood with oxygen ("double breathing").

160. Consider the drawing. Label the numbered parts of the bird's reproductive system.

1.Ovary
2.oviduct
3.cloaca
4. kidney
5.ureter
6.seed tube
7.testis

161. Describe the process of reproduction and development of the bird.
During the breeding season, birds form pairs.
Eggs in birds are large, rich in yolk, ripening unevenly. The ripe egg enters the oviduct. In the upper part, fertilization takes place. The walls of the oviduct contract, pushing the egg (fertilized egg) towards the cloaca. When moving, it becomes covered with shells. First, the egg is covered with protein, then with two fibrous (sub-shell) and then with a shell. The egg enters the cloaca and is laid out.
Bird eggs are large, contain many nutrients in the protein and yolk.
The embryo in the egg develops very quickly, at a high temperature (37 -38 ° C) and a certain humidity. By the end of development, the chick fills the entire internal cavity of the egg.
When hatching, the chick breaks through the parchment shell, pushes its beak into the air chamber and begins to breathe. With the help of an egg tooth (a tubercle on the beak), the chick breaks the shell and gets out of it.

162. Perform laboratory work "External structure of a bird".
1. Consider the external structure of the bird. Describe the shape of her body, the color of the plumage.
The body of the bird is covered with feathers, the front limbs are modified into flight organs - wings. The legs of birds are massive, have four sections: thigh, drumstick, tarsus and 4 toes. The bird has a beak and eyes on its head. The body shape is streamlined. The color of the feather cover is camouflage.
2. Draw and label the body parts of the bird.
see question 152.
3. Examine the bird's head. What organs are located on it?
Eyes, ear holes (covered with feathers - middle ear only), beak, nostrils.
4. Examine the limbs of the bird. What are the features of their structure?
For flight, modified forelimbs - wings serve. The legs of birds have four sections: the thigh, drumstick, tarsus, and toes. Usually the legs are four-toed, but sometimes the number of toes is reduced to three or even two. Of the four fingers, in the overwhelming majority of cases, three are directed forward, and one is directed backward.
5. Examine the feathers of the bird. Draw designs of different types of feathers.

6. Sketch the outline of the outline of the pen. Sign parts of it.

7. What features of the external structure of a bird are associated with its fitness for flight?
see question 152.

163. Consider the pictures. Write the names of the ecological groups to which the birds depicted belong.

1.forest birds
2.birds of open spaces
3.waterfowl and birds of water bodies and coastal areas
4.birds foraging in the air
5.day birds of prey

Review the general characteristics and classification of the Chordate type.

Explore the aromorphoses of the Bird class. Write it down in a notebook.

Study the structure of birds. Complete notes in a notebook.

Consider stuffed birds of different species.

To study the external and internal structure of birds using the example of a Dove (opening a dove).

In the album, complete 7 drawings indicated in the printed manuals V (red check mark). In the electronic manual, the drawings that must be completed in the album are presented at the very end of the text.

In a notebook, write down and learn the classification of modern birds.

In a notebook, draw and fill in table 1 .:

Table 1. The structure of the bird's egg.

In a notebook, draw and fill in table 2 .:

Table 2. Diversity of birds.

Know the answers to Control questions themes:

General characteristics of the Chordate type. Classification of the Chordate type.

Features of the organization of birds.

Systematic position, lifestyle, body structure, reproduction, significance in nature and for humans of the Dove.

General characteristics of birds

In modern animal taxonomy Birds(Aves) is a class in the Chordata subtype of the Vertebrata subtype.

Basic aromorphoses(aromorphoses are major evolutionary changes leading to a general complication of the structure and organization of the organism) The birds are as follows:

the appearance of a four-chambered heart;
complete separation of arterial and venous blood flow;
perfection of thermoregulation;
the formation of spongy lungs;
progressive development of the nervous system;
ability to fly;
adaptive behavior.

Birds- warm-blooded animals capable of flying. They settled around the globe, settled in various places, and also mastered the air habitat. Currently, more than 8 thousand species are known, united in 35-40 orders.

Birds appeared at the beginning of the Jurassic period (195 million years ago), and maybe a little earlier - even in the Triassic of the Mesozoic era (230 million years ago), from ancient reptiles, from which dinosaurs also originated.

The structure of birds

The structure of birds is considered on the example Dove(type Chordates, subtype Vertebrates, class Birds, order Pigeon-like). Dove lives in forests, mountains and cities, everywhere. Pigeons nest on trees, rocks, in buildings, hollows. They live in pairs, in colonies. There are 2 eggs in a clutch. Both the female and the male hatch eggs. The hatched chicks are naked, blind and require long-term parental care. Both parents take care of the chicks, who first feed them with "goiter milk", and then regurgitate them partially digested food. Already fully fledged chicks leaving the nest switch to grain feeding. The gray dove is the ancestor of numerous breeds of decorative and carrier pigeons.

So, the body of streamlined birds consists of a small head, neck, body and tail. The front legs are the wings, the hind legs are the legs. There is a beak on the head, which consists of a beak and a lower beak. The beak is covered with a horny sheath. At the base of the beak there are openings of the nostrils, adjacent to them is an area of soft bare skin - wax. On the sides of the head are large eyes, protected by the upper and lower eyelids and the blinking membrane. Behind the eyes are the external auditory openings. The neck is long and flexible.

Cover. The skin is thin and dry. A single skin gland at the base of the tail (coccygeal) secretes a fat-like secretion for lubrication

General characteristics of birds

feathers (elasticity, water-repellent property). The skin is covered with feathers (Fig. 1, 2).

The feather consists of a quill, a shaft and a fan (Fig. 2). The fan is formed by barbs of the first and second order, which are connected by hooks, forming a closed plate. Contour feathers on the tail are called tail feathers, on the wings - flight feathers, and on the ventral and dorsal sides of the body - coverts. The wing plane is formed by two rows of contour, flight feathers, covered with overlapping cover feathers (streamlined body shape). Down feathers are located under the cover feathers. The change in feather cover is accompanied by seasonal molting. Its functions are: the acquisition of seasonal coloration, demonstration coloration during the mating season and thermoregulation. Areas covered with contour feathers alternate with areas of bare skin. By giving off excess heat, unfeathered areas protect the body from overheating. On the lower part (tarsus), the fingers are covered with horny shields.

The characteristics of the feathers are discussed in table 1.

Rice. 1. Types of feathers.

1 - contour pen; 2 - side feather of the wood grouse; 3 - down feather; 4 - threadlike feather; 5 - bristle; 6 - down itself.

General characteristics of birds

Rice. 2. The structure of the feather.

1 - fan; 2-barrel; 3 - down part of the fan; 4 - top hole; 5 - ochin; 6 - bottom hole.

Table 1. Types of feathers in birds.

Feather types	Structure
Contour	They consist of a hollow rod to which the fans are attached. The fan consists of first and second order barbs. The latter have hooks connecting them together.	Create bearing planes (wings, tail); shape the body contour; protect the body from mechanical stress; have thermal insulation properties
	Thin stem, no second order barbs - no closed fan	Thermal insulation
	The stem is shortened, and the barbs extend from it in one bunch	Thermal insulation
Filiform	Down feathers without barbs	Signals about air currents under feathers
	Feathers with an elastic shaft without barbs. Found in the corners of the mouth of insectivorous birds that forage in the air	Increasing the catching surface of the mouth

General characteristics of birds

Skeleton has structural features due to adaptation to flight and walking on land only on the hind limbs. The lightness of the skeleton is ensured by the pneumaticity of the bones (the presence of air cavities in the tubular bones). The strength of the skeleton is ensured by the fusion of individual bones (sternum, complex sacrum).

The skeleton consists of an axial skeleton (spine), a head skeleton (skull), and a limb skeleton. The skeleton of a bird is shown in Figure 3.

The spine is divided into five sections: cervical includes 14 movably connected vertebrae. Pectoral consists of five vertebrae fused together. Together with the ribs and sternum, they form the rib cage. There is an outgrowth on the sternum - a keel, which increases the area of attachment of the pectoral muscles. Lumbar formed by six vertebrae, merged into one continuous bone plate. Sacral consists of two vertebrae. The last thoracic vertebra, all lumbar, sacral and anterior caudal (five) vertebrae grow together into a single complex sacrum. Tail consists of 15 vertebrae. The anterior five vertebrae are part of the complex sacrum, the middle six remain free, and the four posterior vertebrae merge to form the coccygeal bone (pygostyle), to which the bases of the tail feathers are attached.

Scull large, movably articulated with the spine by means of one condyle. Consists of a large cerebral region and jaws, covered with horny sheaths, forming a beak (without teeth). The skull has a narrow base and very closely spaced walls of huge eye sockets. Fusion of bones occurs with the disappearance of the seams of the skull (strength, lightness of the structure).

Limb skeleton includes the girdle and skeleton of free limbs. Shoulder girdle consists of three paired bones: scapula, clavicle and crow bones. Both collarbones grow together in a fork, which gives the belt elasticity. Pelvic girdle durable, resistant. Paired pelvic bones fused with the lumbar and sacral spine and the first caudal vertebrae.

Skeleton of free limbs: the forelimbs are transformed into wings and consist of the shoulder, forearm and hand. The bones of the wrist and metacarpus merge to form a buckle. Of the fingers, only three are preserved - the second, third and fourth, while the third finger has two phalanges, and the second and fourth have one each. The hind limbs serve for movement on the ground and consist of the thigh, the tibia (the tibia is rudimentary and grows to the tibia) and the tarsus (the fused bones of the tarsus and metatarsus). There are four fingers, three of them are directed forward, one - back.

General characteristics of birds

Rice. 3. Skeleton of a pigeon (diagram).

1 - upper jaw; 2 - lower jaw; 3 - cervical vertebrae; 4 - shoulder; 5 - thoracic vertebrae; 6 - clavicle; 7 - crow's bone; 8 - sternum; 9 - keel; 10 - shin; 11 - tarsus; 12 - thigh; 13 - pelvis; 14 - coccygeal bone; 15 - caudal vertebrae; 16 - ribs; 17 - forearm; 18 - brush; 19 - scapula; 20 - skull; 21 - toes.

General characteristics of birds

Rice. 4. Internal structure of a bird (pigeon).

1 - trachea, 2 - goiter, 3 - singing (lower) larynx, 4 - jugular vein, 5 - ventricles of the heart, 6 - right atrium, 7 - aorta, 8 - unnamed artery, 9 - pulmonary arteries, 10 - lungs, 11 - liver, 12 - small intestine, 13 - pancreas, 14 - large intestine, 15 - cecum, 16 - cloaca, 17 - factory bag, 18 - ureter, 19 - kidney, 20 - testis, 21 - gizzard.

General characteristics of birds

The internal structure of the bird is shown in Figure 4.

Muscular system highly developed and differentiated. The most developed are the muscles of the chest, which ensure the movement of the wings. Paired large pectorals, attached to the sternum and its keel, serve to lower the wing, the subclavian muscles - to raise the wing. The long muscles of the neck provide complex head movements. The strongly developed muscles of the hind legs are designed for movement on the ground.

Nervous system consists of the spinal cord and brain with nerves extending from them. The brain is represented by the following departments:

1. Forebrain has developed large hemispheres. Their surface contains an accumulation of nerve cells that form the archipallium. However, most of the forebrain is formed by the striatum. There are no furrows and convolutions. The hemispheres regulate complex forms of bird behavior, the visual lobes are highly developed, and the olfactory lobes are weak.

2. Diencephalon poorly developed. On the upper side is the pineal gland, and at the bottom, behind the optic nerve intersection, is the large pituitary gland.

3. Midbrain has well-developed visual hillocks.

4. Cerebellum well developed due to coordination of movements and balance during flight. Consists of a middle lobe - a worm and two lateral protrusions. Behind it covers the midbrain and part of the medulla oblongata.

5. Medulla passes into the spinal cord.

12 pairs of cranial nerves depart from the brain.

Spinal cord has a thickening in the shoulder and lumbar regions, where nerves extend from it to the front and hind limbs, forming the brachial and pelvic plexus.

Sense organs. Vision and hearing are leading. Organ of taste- taste buds in the throat. Olfactory organ poorly developed. Organ of vision very well developed. The eyeballs are large, located on the sides of the head. The field of view of each eye is 150 °, and the field of binocular vision is 30-50 °. Visual acuity is very high. The image on the retina is large, which makes it possible to distinguish the details of the object. The retina has a high density of photoreceptors, birds can distinguish colors and shades. Accommodation (double) is carried out by changing the shape of the lens (under the action of the ciliary muscle) and simultaneous movement relative to the retina. In the area of the blind spot there is a vascular formation - a ridge, which is a source of nutrients and oxygen. The mechanical strength of the eyes is provided by the thickening of the sclera and the appearance of bone plates in it. The eyelids are well developed. There is a blinking membrane (third eyelid). Organ of hearing developed

General characteristics of birds

OK. Consists of the inner and middle ear. In the inner ear, the outgrowth of the round sac lengthens and the number of sensory cells increases. In the middle ear, the size of the tympanic cavity increases, the shape of one auditory ossicle, the stapes, becomes more complicated, which increases its mobility. The size of the tympanic membrane increases. The eustachian tubes open into the pharynx with one common opening. The rudiments of the outer ear appear, and there is an auditory canal ending with the tympanic membrane. Organs of the cutaneous sense of touch- an accumulation of sensitive cells that respond to changes in the position of feathers. Thermal detectors register changes in body temperature, consist of an accumulation of sensitive cells, braided by nerve endings.

Digestive system associated with the peculiarities of life processes. Warm-bloodedness and high mobility of birds require significant amounts of food and its rapid assimilation. Food in the gastrointestinal tract is rapidly digested due to the activity of digestive enzymes and an increase in the absorbing surface of the intestine. The horny edges of the jaws form a beak that serves to capture food. No teeth. The tongue is muscular, conical, and has keratinized spines for retaining food. The ducts of the salivary glands with digestive enzymes. The pharynx has a laryngeal slit with a respiratory system. The esophagus is long and easily stretchable, the lower part of it forms a temporary receptacle for food - goiter. The stomach is divided into two sections: glandular, with thick walls that secrete digestive juices; muscular, with an inner dense horny surface, where food moistened with digestive enzymes is mechanically processed by muscle contractions and crushed by pebbles (gastroliths).

The intestine is long, differentiated into the duodenum (the ducts of the liver and pancreas open), the small intestine, paired blind and short large intestine, ending in the cloaca. The rectum is very short, and undigested food debris, without accumulating, is quickly excreted. On the dorsal side of the cloaca there is a blind outgrowth - the bag of fabrice, which performs the function of an endocrine gland and participates in the body's immune defense. The liver is large, bilobed. The pigeon has no gallbladder.

Respiratory system consists of a complex system of airways and lungs. The airways include the nostrils, nasal cavity, nasopharynx, larynx, and long trachea. In the place of branching of the trachea into the bronchi, there is a lower larynx, which is characteristic only of birds. It contains the vocal cords, which vibrate and emit sounds when air passes. The variety of sounds emitted is controlled by the contraction of specific singing muscles. Lungs - dense spongy bodies, low stretch, with a small volume. Consist of branched bronchial tubes. The main bronchus enters the lung and gives 15-20 branches (secondary bronchi), interconnected by parabronchuses with numerous outgrowths (bronchioles), braided by a network of blood

General characteristics of birds

capillaries (gas exchange occurs). Part of the bronchial branches (4-5 bronchi) extend beyond the lungs and form thin-walled expansions - air sacs located between the internal organs. In terms of volume, they are about 10 times the volume of the lungs. There are paired air sacs (cervical, prothoracic, posterior and abdominal) and unpaired air sacs (interclavicular). The outgrowths of air sacs penetrate into the cavities of large bones. The importance of air sacs: cooling and lightening the body, "pumps" that pump air into poorly expandable lungs (gas exchange in the bags does not occur). Thoracic respiration mechanism. With the expansion of the chest, inhalation occurs, with the relaxation of the pectoral muscles and the narrowing of the chest cavity, exhalation. Unlike all terrestrial vertebrates, birds are saturated with oxygen through the lungs both during inhalation and exhalation (the so-called double breathing).

Circulatory system closed, has two circles of blood circulation. The heart is four-chambered (the right half contains venous blood, the left - arterial), therefore arterial and venous blood are completely separated, which ensures a high metabolic rate (warm-blooded animals). Two independent vessels depart from the heart: the pulmonary trunk (carries venous blood) and the right aortic arch (arterial blood).

Small circle of blood circulation. The pulmonary trunk departs from the right ventricle, which, when exiting the heart, is divided into the right and left pulmonary arteries. Gas exchange takes place in the lungs, and oxygen-rich arterial blood flows through the right and left pulmonary veins into the left atrium.

A large circle of blood circulation. From the left ventricle, the right aortic arch departs, which, when exiting the heart, is divided into two vessels: the right and left unnamed arteries, each of which branches into the common carotid and subclavian arteries (brachial and thoracic). The right aortic arch wraps around the heart and forms the dorsal aorta. All organs of the body are supplied with arterial blood. Venous blood from the posterior parts of the body is collected through the inferior vena cava and flows into the right atrium, after being cleared through the portal system of the liver and kidneys. Venous blood from the front of the body is collected in the anterior vena cava, which flows into the right atrium. The heart is large compared to the size of the body. The high speed of blood circulation through the vessels is ensured by a high heart rate.

Excretory system represented by the pelvic kidneys (metanephros, secondary kidney). The relative size of the kidneys in birds is large and is directly related to the very intensive general metabolism. The ureters depart from the kidneys and flow into the cloaca. The end product of the exchange is uric acid. Urine passes through the excretory tract quickly due to the poor solubility of uric acid, the possibility of blockage of the pathways by urinary salts, and is excreted in the form of white crystals along with the droppings. This is related to the lack of

General characteristics of birds

birds of the bladder. The loss of water during urination in birds is small, since water is reabsorbed in the cloaca.

The reproductive system. Divided. The sex glands are paired. In males, bean-shaped testes, suspended on the mesentery, are located above the upper lobe of the kidneys. The size of the testes varies with the seasons. By the breeding season, the volume of the testes increases 1500 times. Weakly expressed appendages join the inner edges of the testes, from which the vas deferens depart, located parallel to the ureters and flowing into the cloaca. In some species, the vas deferens, before flowing into the cloaca, form an expansion - seminal vesicles (seed reservoir). There is no cumulative body. Fertilization is internal (in the upper parts of the oviduct), by bringing the openings of the cloaca of the female and male closer together. In females, the reproductive system consists of a left ovary and a left oviduct that opens into the cloaca. The reason for the reduction in the right half is apparently associated with the laying of relatively large eggs with a hard shell. The ovary is granular, irregular in shape, located in front of the left kidney. Its size is different depending on the maturity (size) of the eggs being formed. The oviduct looks like a long tube, one end of which opens into the cloaca, and the other funnel into the body cavity. The initial section of the oviduct is rich in glands that secrete a protein that thickly covers the passing egg. In the next section, the egg is covered with shell membranes. In the uterus, a calcareous egg shell and staining of the supra-shell membrane are formed. The last part of the oviduct (vagina) is short and has significant muscles, from which the egg goes into the cloaca and further out. The entire period of passage of the egg through the oviduct is 41 hours for a pigeon.

Birds are amniotes, i.e. by vertebrates, whose embryos have embryonic membranes that ensure the development of the embryo in the ground-air environment.

Development in birds, it is straight. The female pigeon lays two eggs in the nest. By type of development, pigeons are nesting (nesting) birds. The development of the embryo begins as a result of warming the egg (incubation for 16-19 days). As it develops, a feather coat appears, a beak, and a tail disappears. Before hatching, the chick breaks through the inner shells of the egg with its beak and breathes with its lungs in the air chamber. Then, with a tubercle on its beak, the chick breaks through the egg shell and comes out of it. The hatched chicks are naked, blind and require long-term parental care. Both parents take care of the chicks, who first feed them with "goiter milk", and then regurgitate them partially digested food. Already fully fledged chicks leaving the nest switch to grain feeding. The bird egg structure is shown in Table 2. The differences between chicks and brood chicks are described in Table 3.

Seasonal phenomena in the life of birds. All birds can be divided into migratory, nomadic and sedentary. Migratory birds (ducks, geese, swallows) include species

General characteristics of birds

which migrate considerable distances from nesting sites. Wandering birds (woodpeckers, titmice, bullfinches) do not make regular flights in strictly defined directions, they winter close to their nesting sites. Resident birds (rock dove, sparrows, jackdaws) migrate within the same area where they breed.

Bird ecology. Birds are adapted to different habitats, which is the reason for the emergence of ecological groups among them (Table 4). Each group is tied to their habitats, uses their own food and has certain adaptations for obtaining them.

Features of adaptation of birds to flight: transformation of the forelimbs into wings; streamlined body covered feathers; the formation of the sternum in the form keel, with powerful muscles that control the wings; double breathing, providing intensive metabolism; lightweight skeleton(hollow bones); weight loss due to the absence of a bladder, one ovary, teeth, rectum, copulatory organ; Availability high visual acuity and the progressive development of the brain, in particular the cerebellum.

Table 2. Poultry egg structure.

	Structural elements
Egg shells
Shell	Dense porous lime shell	Protective - from mechanical damage and the penetration of bacteria. Providing gas exchange
Under-shell casings	Formed by a network of organic fibers. The spaces between the fibers are filled with air	Providing gas exchange
Air chamber	In the process of gas exchange, the egg loses water. The evaporated water is replaced by gas, which forms an air chamber. The camera goes into the space between the fibers of the shell shells	Providing gas exchange (at a certain stage, the chick pierces the inner shell and begins to breathe air from the chamber)

General characteristics of birds

Table 2. (end)

	Structural elements
	Made up of 87% water, 13% protein and other substances	Protective - from mechanical damage. Water source
Yolk (egg itself)	Contains 50% water, 23% fat, 16% protein, 11% lipoids	Storage - nutrients, water. Material for embryo formation
Chalazes (ropes)	Consist of dense protein	Securing the position of the embryonic disc (shock absorbers)
Embryonic membranes
	The membrane that surrounds the embryo. Between the embryo and the amniotic membrane is the amniotic fluid in which the developing embryo is located	Protective
Allantois	The outgrowth of the hind gut, into which metabolic products enter. It gradually grows and adheres to the shell. Blood vessels develop in it	Providing gas exchange
Serous membrane (serosa,	Outer germinal membrane	Trophic

General characteristics of birds

Table 3. Types of development of chicks.

Brood

Chicks

Covered with down;

able to move

(a few hours after birth, follow the parents);

able to feed on their own;

the size of the clutch is determined

the possibility of incubating masonry

Naked or nearly naked;

unable to walk;

not capable on their own

feed;

the size of the clutch is determined

the ability to feed chicks

Representatives: ostriches, chickens, anseriformes, bustards, waders

Representatives: passerines, woodpeckers, dove-like, swift-like, diurnal carnivores, owls

Table 4. Ecological groups of birds.

Habitat		Representatives
Birds of the forest	Tit, pika, kinglet, nuthatch		Thin strong beak. Tenacious and sharp claws, long fingers. Tough tail feathers. Migration
	Great spotted woodpecker		Chisel-shaped beak, long, thin and hard tongue. Long, tenacious fingers (two are directed forward and two are directed back). Tail feathers are tough and resilient. It feeds on insect larvae, in winter - on seeds of conifers. Sedentary

General characteristics of birds

Table 4. (continued)

Habitat			Representatives			Features of the structure and nutrition
Birds of the forest		Hazel grouse, black grouse, wood grouse, pheasant, partridge			They spend a lot of time on the ground. Scaly fringes (in hazel grouse), feathers (in partridges) help to stay in the snow without falling through. Strong legs armed with large claws; three fingers help to rake the forest floor. A strong, bent down beak helps to bite off buds, berries, young shoots of plants. The wings are short and wide
Birds of the forest					Curved scissor beak designed for hulling seeds from coniferous cones
Birds open air spaces		Swallow, swift, nightjar			Long, narrow wings, notched tail - rudder in flight. The beak is small, with a large oral funnel of bristle-like feathers at the corners of the mouth. Legs are short, tightly pressed to the body during flight. They feed on insects in the air. Migration
Birds of the steppes and deserts		Great bustard, African ostrich, little bustard, crane			Omnivores. Protective coloration, nest on the ground. The coccygeal gland is poorly developed. The huge paw of a flightless African ostrich has only two toes. Long legs, neck and beak. Migratory (Crane-like squad)
Birds open plots reservoirs	Duck, goose, swan, night heron, crested grebe			Swim well, many dive. The body is flattened, the legs are shifted far back, with membranes on the toes. The plumage is dense, the coccygeal gland is well developed. The beak is flattened, with horny denticles along the edges. Migration
Birds of coasts, reservoirs and marshes	Stork, heron, sandpiper, bittern			Long thin legs (very long fingers and small membranes) and neck, long beak (compressed from the sides). They feed on frogs, fish, molluscs, worms, insects. They nest on the shore, not far from water, some arrange nests in trees. Migration

General characteristics of birds

Table 4 (end)

Habitat	Representatives	Features of the structure and nutrition
Seabirds	Seagull, guillemot, water cutter, puffin, cormorant	They form bird colonies on steep cliffs, feed on fish. Tongs beak or harpoon beak for catching fish from the air and under water. Sedentary
Predator birds	Eagle, falcon, vulture, hawk, kite, owl	Predators. Excellent vision, powerful wings, sharp curved claws and a hooked beak. Many birds of prey can hover for a long time using warm currents of rising air. Sedentary

Bird class- warm-blooded animals, the body of which is covered with feathers (the only group of animals), and the forelimbs are turned into wings; hind limbs - legs. Birds fly beautifully, surpassing all other vertebrates in this respect. Also, birds move well on the ground, climb trees, many dive and swim in the water. Birds are extremely diverse in size, shape, color, habits and have adapted to living in various climatic conditions. There are about 9 thousand species.

External structure of a bird

Birds have a head, neck, torso, limbs and tail. The head of birds is small, it has a beak, eyes, nostrils. The beak is formed by bony jaws extended forward, which are covered from above with horny sheaths. Birds have no teeth, which makes the skull lighter. The nostrils are located at the base of the upper part of the beak. The rounded eyes are covered with two eyelids and a blinking membrane. Closer to the back of the head, under the feathers, the ear holes are hidden. A movable neck connects the head with a compact torso.

Features of the body structure of a bird

Signs	Features of the structure of the body of birds
Body shape	Streamlined
	Dry skin covered with horny feathers
Feather types	1. Contour - creates the shape of the body and helps with the flight; 2. Down feather and down - keep warm
	Lightweight and durable due to: Fusion of bones (bones of the hand, pelvis, skull) Air cavities inside the bones The flight muscles are attached to the keel (sternum)
	Large pectorals (lower wings); Subclavian (raise the wings)
Digestive system	Digestion of food in 2-3 hours (rapid metabolism to maintain a constant body temperature) Beak -> pharynx -> esophagus (with goiter) -> stomach (from two sections - muscular and glandular) -> intestines -> cloaca
Respiratory system	Cellular lungs and additional air sacs in the body cavity and bones - to improve gas exchange and protect against overheating. Breathing is double.
Circulatory system	Four-chambered heart (two atria and two ventricles), two circles of blood circulation
Nervous system	The cerebellum is well developed; Developed hemispheres of the forebrain (complex behavior, instincts)
Reproduction	Fertilization is internal, the female lays eggs containing a supply of nutrients for the embryo and protected by a calcareous shell and an undershell membrane
Bird development	In the spring: pairing -> mating of males -> nesting -> laying eggs (from 1-2 to 15-20 pcs.) -> laying eggs -> taking care of the offspring. Chicks: 1. Brood - they appear dressed in down, with open eyes and can leave the nest and follow their mother. 2. Nest - appear helpless, with eyelids accrete, do not leave the nest for a long time.

The most important orders of birds

Squads of birds	Signs	Representatives
Passerine	Mostly forest birds, have four-toed limbs (three fingers are directed forward, one is directed backward); chicks, live in pairs during the nesting period	Sparrows, larks, swallows, starlings, crows, blackbirds
Charadriiformes	Brood birds, live along river banks, wetlands; medium size, long legs and a thin long beak	Sandpiper, woodcock, lapwing, snipe
Anseriformes	Horny plates or teeth are located along the edges of the beak, and at the end of the beak there is a thickening - leg-current; waterfowl breeding birds	Geese, ducks, swans
Penguins	The wings are narrow, unsuitable for flight, there are swimming membranes on the paws, the legs are carried back, the skeleton is heavy, the feather cover is very dense	Imperial ping-gwin
Crane like	Birds of open spaces, have long legs and neck	Demoiselle crane
	Large birds; have weak wings unsuitable for flying and strong legs	African ostrich
	Short rounded wings (fly hard), four-fingered legs, with large claws and densely feathered, relatively large beak	Grouse, black grouse, quail, partridge, wood grouse
Daytime predators	Long, sharp hooked claws; the beak is short, curved; fast flight	Falcons, eagles, hawks, vultures
	Nocturnal birds of prey, with strong curved beaks and sharp claws, keen hearing and keen eyesight, have loose and soft plumage, which allows them to fly silently	Owl, owl, barn owl, scops owl