Most representatives of the class of birds have mastered the ground-air habitat. The adaptation of birds to flight is due to the peculiarities of their external and internal structure. In this article, we will look at these aspects in more detail.
Bird adaptations for flight
The main features that allow birds to master the air environment are:
Feather cover;
Modification of the forelimbs into wings;
warm-blooded;
Light skeleton;
The presence of a special bone - the keel;
double breath;
shortened intestine;
The absence of one ovary in females;
Well developed nervous system.
These structural features illustrate how birds are adapted for flight.
Skeleton structure
With ease, it becomes possible for birds to rise up, first of all, thanks to their light skeleton. It is formed by bones, inside of which there are air cavities. The main sections are the skull, spine, belts of the upper and lower extremities, and the free limbs themselves. Many bones fuse together, providing strength to the entire "construction". Distinctive feature the skeleton of birds is the presence of a keel. This is a special bone to which the muscles that set the wings in motion are attached. It is unique to birds.
covers
The features of bird adaptation to flight are largely related to the characteristics of the integument. Feathers are the only group of animals whose body is covered with feathers. They can be grouped into three groups. The first is called "contour". Thanks to them, the body of the bird acquires a streamlined shape. Depending on the location on the body and the functions performed, the contour wings are covering, fly and steering. They cover the body, forming the contours of the wings and tail. Regardless of the type, each wing consists of a central part - a rod, on most of which there are fans formed by barbs of the first and second order with hooks. The lower bare section of the feather is called the chin.
The second group is represented by down feathers. Their beards are devoid of hooks, so the fans are not linked, but free. The third variety is fluff. characteristic feature its structures are fluffy beards, which are located in a tuft at one end of a strongly shortened chin.
On the example of the features of plumage, it is easy to see how birds have adapted to flight. It provides thermoregulation, determines the color, the ability to move in the air. By the way, the color of birds can serve both as a disguise from predators, and as one of the forms of demonstrative behavior.
warm-bloodedness
This adaptation of birds to flight is very important. Warm-bloodedness means the presence of a constant body temperature, independent of environment. After all, as you know, with height, the air temperature decreases significantly. And if the birds were cold-blooded, like fish or amphibians, they would simply freeze during the flight. This feature is inherent in this group of organisms due to the progressive structure of the circulatory system. It is represented by a four-chambered heart and two circles of blood circulation. Therefore, venous and do not mix, the exchange of gases and substances occurs very intensively.
External structure
The body of birds is divided into the following parts: head, movable neck, trunk, tail and limbs. On the head are eyes, nostrils and a beak covered with horn covers. The lack of teeth makes the skull even lighter. The eyelids are motionless in front of the eyes, the cornea is moistened with the help of nictitating membranes.
The main adaptation of birds to flight, of course, lies in the modification of the upper limbs. They are transformed into wings. Legs - lower limbs, often covered with horny scales. This feature of the structure remained in birds from their ancestors - reptiles. The claws located on the toes help the birds to stay on the supporting surface.
The internal structure of birds
The adaptation of birds to flight is also reflected in the structural features of most internal organs.
The digestive system is represented by the oral cavity, the esophagus, which forms an expansion - goiter. In it, the food undergoes additional enzymatic processing, becomes soft and digested faster. Further, food enters the stomach, which consists of two sections: glandular and muscular, and then into the intestines. It opens outwards with a cloaca. The intestines of birds are shortened compared to other animals. This structure also makes their body lighter. Undigested food remains do not stay long in the intestines and can be excreted through the cloaca even during the flight.
The adaptation of birds to flight can also be traced. Thanks to its development, animals have fairly clear color vision, which makes it easy to navigate in the air even at a fairly high altitude. Hearing functions well. And thanks to the developed cerebellum, the Birds are at a high level and quickly react during an approaching danger or hunting.
Compactness is a characteristic feature of the reproductive system. The testicles of males are small, bean-shaped. They open their ducts directly into the cloaca. Females have only one ovary. This structure makes the weight of the birds significantly less. The egg from the gonad moves along the oviduct, where the fertilization process takes place, the egg is covered with shells and calcareous shells. Then it goes out through the cloaca.
Breathing Features
The adaptations of birds to flight also concern. Indeed, for the intensive work of the muscular system, a continuous supply of tissues and organs with oxygen is necessary. Therefore, along with pulmonary respiration, birds have additional organs - air sacs. These are additional air reservoirs with a sufficiently large volume. Therefore, the breath of birds is also called double.
Adaptation of birds to the environment
The features of the external structure often change depending on the habitat. For example, a woodpecker living in the forest has sharp claws. With their help, he moves along the branches of trees, leaning on a tail with hard feathers. The beak of this bird is like a chisel. Using it, as well as with the help of a long sticky tongue, he takes out insects and larvae from the bark, seeds from cones.
Birds - inhabitants of water bodies, also have a number of important adaptations. These are short lower limbs with swimming membranes, a dense feather cover, lubricated with a water-repellent secretion of special glands. "Get out of the water dry" - this proverb, known to everyone, appeared due to the peculiarities of life
Inhabitants of open spaces - steppes and deserts, have a protective coloring of feathers, very powerful legs and excellent eyesight.
The birds of the coast are masters of gliding flight. Albatrosses, gulls and petrels are characterized by strong and long wings. But they have a short tail. All this allows coastal inhabitants to fish directly from the air.
Is it possible to see prey at a distance of up to a thousand meters? For this it is not a big deal. Falcon, hawk, eagle are bright representatives of this group. They have a large curved beak with which they grab and tear food. And powerful sharp claws leave no chance of salvation. Predators are able to soar in the air for a long time thanks to their very wide wings. And those of them who hunt at night, additionally have sharp eyesight and perfect hearing. For example, owls and owls.
Do all birds fly
Not all representatives of this class are able to fly. For example, penguins are excellent swimmers, their upper limbs are modified into flippers. But these birds cannot fly. They have a keel, but their large weight does not allow them to soar into the air. And a thick fat layer and dense plumage are simply necessary for life in the harsh conditions of the north.
The ostrich superorder unites emu, kiwi, cassowary, rhea. These feathered keels are absent. And the inability to fly is compensated by a fast run. This skill saves birds in the conditions of flat Africa.
The vast majority of modern birds are perfectly adapted to flight and habitat. They live in the forest, on water bodies and their coasts, steppes and deserts.
Representatives of the class of birds are striking in their diversity, are important in nature and human life, and character traits structures determine the ability to fly.
slide 1
Slide text:
Presentation on the topic
“Features of the internal structure of birds. Features of the fitness of a bird for flight
field lark
Compiled by biology teacher
Abretsova Tatyana Vasilyeva
slide 2
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The place of birds in the wildlife system
Kingdom: Animal
Type: Chordates
Class: Birds
slide 3
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The ability to move in the air, warm-bloodedness and other features of the structure and life gave them the opportunity to widely settle on Earth.
Birds are vertebrates whose body is covered with feathers, and whose forelimbs are turned into wings.
blackbird
slide 4
Slide text:
Nature gave the birds unique clothes that
Nature has given the birds a unique clothing-feather cover that warms in the cold, protects and, most importantly, it is clothing for flight.
covers
slide 5
Slide text:
Feathers make the body streamlined and provide flight. According to their purpose, they are divided into flight feathers (primary and tail feathers) and coverts (head, body, wings, tail). When a bird is cold, it fluffs up its plumage, reducing its thermal conductivity. When the bird is hot, it presses the plumage, increasing its thermal conductivity.
slide 6
Slide text:
bird skeleton
The skeleton of a bird is light because the bones are hollow
Lime salts and strong bone joints
give them strength.
The lightness and strength of bird bones are the adaptation of birds to flight.
Slide 7
Slide text:
Slide 8
Slide text:
Zoryanka - robin
fast food lovers
The digestion process is fast. In small birds 8-10 minutes.
Slide 9
Slide text:
The structure of the digestive system
pharynx
esophagus
stomach
intestines
glandular
muscular
thin
thick
cloaca
without teeth
Slide 10
Slide text:
Most Efficient Breathing
Circular air path
Air bags
slide 11
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Principle of double breathing
trachea
bronchi
Air bags
lungs
Air
bags
trachea
lungs
slide 12
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The heart is four-chambered;
Two circles of blood circulation;
The heart beats at a high rate
goshawk
The most perfect circulation
slide 13
Slide text:
big circle
blood circulation
pulmonary artery
Circulatory system
Lower
hollow
vein
Slide 14
Slide text:
excretory system
The excretory system in birds consists of
kidney,
No ureter, no bladder.
Excretion is carried out through the cloaca
What do you think is the reason for the absence of the bladder?
slide 15
Slide text:
highly developed nervous
system
great tit
Significant development of the brain, the volume is 10 times greater than that of reptiles;
Can be trained;
Sense organs: sight, hearing, smell
slide 16
Slide text:
Give examples of more complex behavior.
Choose a conditioned reflex from the given test:
1. Nest building
2. Search for food
3. They resort to the voice of the poultry
4. Feeding the chicks.
bird nesting,
- caring for offspring
- flight of birds,
- formation of conditioned reflexes
Birds have more complex behavior than reptiles.
Give examples of complex bird behavior.
nesting
care of offspring
bird flights
formation of conditioned reflexes
Choose an example of a conditioned reflex in the test:
1 foraging
2 nest building
3 resort to the voice of the bird
4 bird migrations
1) double breath birds are tricky. Let's try to understand the scheme:
The lungs of birds are spongy, they cannot expand and contract like ours. This work (expand during inhalation and contract during exhalation) in birds is performed air bags. When inhaling(blue arrows) the air sacs expand and air enters. Air that has passed through the lungs (saturated with carbon dioxide, "used") enters bags No. 2. No. 1 bags store clean air. When exhaling(red arrows) bags are compressed. The used air from bags No. 2 is exhaled immediately, and the clean air from bags No. 1 passes through the lungs before being released. In this way, both inhalation and exhalation fresh air passes through the lungs of a bird. That is why bird breathing is called "double". By the way, pay attention: the air through the lungs of birds moves all the time in the same direction, which facilitates the organization of countercurrent. Due to double breathing and countercurrent (it turns out “quadruple breathing”), birds receive much more oxygen than us.
2) To store oxygen flying muscles contain a lot of myoglobin.
3) Circulatory system does not lag behind the respiratory: it has a very high pressure and heart rate. (The average pressure in birds is 133 mm Hg, and in mammals - only 97 mm Hg. But the pulse of a half-kilogram mammal will be about 250 times per minute, and in a similar bird - only 180. But the mass of the bird's heart is an average of 0.8% of body weight, compared to only 0.6% in a mammal. .)
4) Due to the well-developed circulatory and respiratory systems, birds have a very fast metabolism and high body temperature (in mammals from 36 to 39 ° C, and in birds - from 40 to 42 ° C). At high temperatures, all life processes go faster, including faster muscle contraction. This allows the birds to do more work per unit of time. For non-physics buffs: work divided by time is called power. Birds over powerful so they can fly.
5) To get a lot of bird energy eat a lot more than mammals with the same body weight (against the background of birds, even a shrew, which has to eat 80 times a day, after eating - sleep for 10 minutes, then eat again - does not look like such a sufferer). To save at least a little, some birds (for example, hummingbirds) decrease their body temperature during sleep ( heterothermia).
2. Aerodynamics
6) Streamlined body shape. In particular, the large muscles that move the limbs are located on the body, and the tendons go to the limbs (that's why the birds are so thin-legged).
7) Chewing food takes place not in the head, but in the stomach (with the help of stones). Relief of the body is unlikely, but heavy chewing devices are at least located in the center of the body ( centering aircraft).
3. Body lightening
8) Feathers, forming the flying surface of the wings, dead (analogues of our hair). They do not need blood vessels to bring food and oxygen, so the feathers are very light.
9) light skeleton filled with air (in the bones there are air sacs from item 1). (In this regard, birds do not have red bone marrow and red blood cells have to reproduce themselves - for this they have a nucleus.)
10) Decreased number of bones especially in the wings and legs.
11) One ovary.
12) There are no salivary glands.
13) no bladder(this is more likely due to the excreted metabolic product - uric acid, which is not poisonous, so it does not need to be diluted).
4. Other features of the skeleton
14) Keel for attaching powerful flight muscles (lowering the wing).
15) The forelimbs have turned into wings(What, didn’t you expect?), so you have to walk on two legs. To reach the ground, large birds have a long, flexible neck.
16) Lumbar vertebrae to create a good base grown together among themselves, with the sacral and caudal vertebrae, as well as with the ilium.
5. Nervous system and sense organs
17) Enlarged cerebellum for better coordination.
18) At a height, sense of smell and hearing are useless, therefore they are developed so-so in birds. But they have the best on earth vision.
Many birds have mastered the ground-air habitat. The adaptation of birds to flight became possible due to many changes in appearance and internal structure.
The main features of the adaptation of birds to flight
- Double breath.
- Flight muscles contain large amounts of myoglobin.
- Feather cover.
- Lightweight skeleton.
- Developed circulatory system.
- Fast metabolism.
- Modification of the forelimbs in the wings.
- Streamlined body shape.
- There is a special bone - the keel.
- Warm-bloodedness.
- One ovary.
- Reduced number of bones.
- The cerebellum is enlarged.
- Well developed nervous system.
How are birds adapted to fly?
In birds, the lungs do not have the ability to expand or contract as they do in humans. Air bags do all this work. When inhaling and exhaling, fresh air moves through the lungs of a bird, which is stored in bags. For this reason, breathing in birds is called "double". In birds, the flight muscles contain a lot of myoglobin to supply enough oxygen.
The internal structure of the bird diagram
Birds have to eat a lot to get a lot of energy. They have a very well developed circulatory and respiratory system. The average pressure of birds is about 130 mm Hg. Art., while in mammals it is only 95 mm Hg. Art.
Birds have a very fast metabolism, body temperature reaches from 40 to 42 degrees. High body temperature significantly affects all vital processes, and muscle contraction occurs many times faster.
To a large extent, the large muscles that move the limbs are located on the body, and the tendons already go to them.
Birds chew their food in the stomach, so all chewing processes are located inside the body, which improves their aerodynamics.
Feathers have feathers that do not need blood vessels, they are too light and soft. Also, in addition to all this, birds have a light skeleton that is filled with air. And for better coordination of movements, the cerebellum was enlarged.
Adaptation of birds to the environment
Depending on the habitat, the external structure of birds is greatly modified. For example, a woodpecker has a beak that looks like a chisel. He uses it to get insects and larvae from the bark of trees. In addition, he has an overly long, sticky tongue and sharp claws that allow him to perform all the necessary tasks to continue living.
Birds that live in water bodies also have some changes. They have short lower limbs with swimming membranes and a continuous covering of feathers. Birds living in deserts and steppes have a protective color of feathers, they have excellent eyesight and strong legs.
Ostrich-like birds inhabit Africa. They cannot fly, as birds have underdeveloped wings, but their legs are well developed. Birds can reach speeds of up to 70 km / h, their weight is 50-90 kg, and their height is about 2.5-2.7 meters. Ostrich-like animals live in savannahs, deserts, and steppes.
- Related article -
Birds of prey have large, curved beaks that are used to tear their prey into small pieces. Having powerful sharp claws, they cling to prey, after which they inflict fatal wounds on them or carry food to their nest. Predators can hover in the air for a long time, they have excellent sharp eyesight and excellent hearing.
Municipal state educational institution "Bogorodsk school No. 8"
Methodical development lesson:
“Features of the internal structure of birds. Features of adaptation of birds to flight
Completed by: biology teacher
S.V. Kulikova
Bogorodsk - 2017
Lesson Objectives:
To study the features of the internal structure of birds associated with flight;
show the place of birds in the wildlife system;
to teach to see the beauty in the world of birds, to show the unity of man and nature.
Lesson objectives:
Educational
To ensure that students acquire knowledge about the life processes of birds,
On the features of the structure of their internal organs in connection with their functions, fitness for flight.
To teach to recognize the organ systems of the bird class, to establish the relationship between the structure and functions of organs.
Educational
Promote the development of logical thinking,
ability to compare, analyze,
Identify cause and effect relationships in nature.
educators
Continue the education of love and respect for nature.
Equipment: bird picture,
use of the presentation “Features of the structure of birds. Features of the fitness of birds for flight.
During the classes
1.Organizing time.
Greeting: Birds are amazing creatures of nature. They - birds are one of the most important natural components, their role is significant. But birds are also an ornament of nature. Entering the forest or walking through the field, we are accompanied by the voices of birds
Question - What is the name of the branch of zoology that studies birds? (ornithology)
What type are birds in the animal kingdom? (Chordates) slide-2
On board: Type: Chordates
Class: Birds
Today we will continue to get acquainted with the Class "Birds", with the structural features of birds in connection with the fitness of birds for flight.
lesson problem: can birds be called living aircraft?
Survey of the material covered
In the previous lesson, we got acquainted with some features of the adaptation of birds to flight. Slides 3.4.5
What are these traits? (Integuments, skeleton and muscles)
At home, you should have started filling out the chart and putting the fitness traits on the chart.
Working with a table
1. The body of the bird is covered with feathers.
What is the meaning of feathers? Students answer.
Nature gave birds universal clothes - feather cover, which warms them in the cold, protects them from attack, and most importantly, this clothing is adapted for flight.
2. What are the structural features of the limbs in birds? Students answer.
Movement in the air is carried out with the help of forelimbs transformed into wings, and tail. The wings serve both as aerodynamic surfaces to keep the bird in the air and as a source of thrust to propel it forward.
When flying, the bird makes rhythmic synchronous movements with its wings.
Let's remember! What do birds need to be in order to take to the air? Student responses.
on the one hand, they must be light in order to rise into the air (comparing a bird to a balloon filled with air. Demonstration of a balloon.
on the other hand, they are very strong, like weightlifters (image of a weightlifter athlete)
Question - What allows a bird to be as light as a balloon and as strong as a weightlifter at the same time?
3. What are the features of the skeleton? Student responses. (slide 6)
bird skeleton has its own characteristics, and they are also associated with flight.
The bones of a bird are very light because they are hollow.. Some bones have air-filled cavities associated with the respiratory organs. However, despite the lightness, the bones of the bird are very elastic and durable. These qualities are absolutely necessary to overcome all the difficulties of flying.
Man also learned to fly. But not with the help of wings attached to the body. After all, man is completely unsuitable for flight, and in order to correct this situation, he needed to come up with something more radical.
What? (eg = aircraft)
What lifts a bird into the sky?
What allows us to raise and lower our hands? Students' answers are muscles.
Teacher - What muscles? Where are they located?
Wing muscles, pectoral muscles.
Teacher - Muscles in birds have reached a high level of development.
The weight of the human pectoral muscles, which move the shoulders and arms, is only one percent of the total body weight, while in some birds this figure reaches 30 percent of the total weight.
Question - Which muscles of birds lower their wings? The answer of the students is Breast.
Birds have a bone in the skeleton - the keel, a special outgrowth of the sternum, allows you to increase the area of attachment of the pectoral muscles, which contribute to the lowering of the bird's wing
Grades for D /Z. (compilation of the table)– for compiling all columns of the table -"5", if not completely filled without the 3rd column - "4", "3" and "2" at the discretion of the teacher.
Explanation of new material
Guys, as we have already learned, the body of birds is perfectly adapted for flight. This is a feather cover, wings, features of the skeleton. People have long dreamed of making wings and flying like birds. And there were craftsmen who made excellent wing designs ... and flew? Answer learn-Xia, their assumptions.
So, having wings is still far from enough to fly.
The purpose of our lesson: further study of the internal structure of birds. Find out if there are any more structural and functional features that help to adapt birds to flight?
Fizminutka.
Work in a notebook: recording the topic of the lesson
Theme "features of the internal structure, traits of birds' fitness for flight":
Digestive system : consider the features of the structure and work of the digestive system (slides 7.8)
1. Guys, look at the pictures of birds. Why don't they have the same beaks? What is it connected with? (with food) student answers.
Peculiarity digestive system - food is digested very fast. For example, a snake digests within 1-2 days, small owls - a mouse - in 3 hours. Juicy berries pass, intestines in 8-10 minutes.
Note the structural features of the digestive system? Slide
Mouth sections no teeth
esophagus - goiter - an enlarged part of the esophagus where food accumulates,
glandular stomach
muscular - an organ in which swallowed pebbles) crush its contents, thereby compensating for the absence of teeth.
small intestine
Conclusion: To compensate for the energy consumption during the flight, the digestive system is adapted to the rapid process of digestion.
Circulatory system - occurred in the circulatory system significant changes.
The circulatory system is closed, 2 circles of blood circulation - large and small (show). slide 10,11
How many chambers in the heart do reptiles have? Name the departments?
Birds have a heart 
chamber - 2 atria, 2 ventricles. The ventricle is completely divided in half by a septum. Thanks to these changes, the blood flows unmixed throughout the body. What does it give the bird? student's answer
What kind of blood moves in the systemic circulation?
Arterial blood moves through the body. What kind of blood is called arterial?
Blood enters the small circle -? Student's answer (Venous).
What kind of blood is called venous? student's answer
What are the functions of the circulatory system? Student's answer (Movement of nutrients and supply of oxygen to the body).
In which organ does blood give carbon dioxide and saturated with oxygen? Student's answer -Easy.
The circulation rate in birds is extremely high, associated with a high heart rate. The bullfinch has 730 times per minute.
Conclusion from the study: due to the appearance of a septum in the ventricle, venous and arterial blood does not mix, and the organs are supplied with oxygenated blood. It happens very quickly.
Respiratory system . (Slide 12.13) Using the manual 1C of the laboratory "Why do we breathe"
Consider the structure and operation of the respiratory system.
The organ where gas exchange takes place lungs. Air enters them through the nostrils larynx trachea bronchi - these are respiratory tubes - the teacher demonstrates a diagram of the structure of the respiratory system. The bronchi enter the lungs and they strongly branch. Many of them end in bubbles, wrapped in a dense network of capillaries.
The metabolism of birds is very fast. 
With body 
. This requires a lot of oxygen. Therefore, there are features in the structure of the lungs. depart from the lungs air bags(Slide show )
which are many times larger than the lungs. When the wings flap, the air fills the lungs and air sacs. The lungs are designed in such a way that air passes through them through and through. When you inhale, only 25% of the outside air remains directly in the lungs, and 75% passes through them and enters the air sacs. When exhaling, the air from the air sacs again goes through the lungs, but outward, forming the so-called double breathing.
For a better understanding of the breathing process, a fragment of the microfilm of the 1C laboratory “Why do we breathe” is shown on the computer. After watching, answer questions. What is breath? Why does the body need oxygen? What is its meaning? (Students began to study chemistry and knowledge about oxygen can apply and justify what they saw. Generalization of the teacher.)
Conclusion: Thus, the lungs are constantly saturated with oxygen, both during inhalation and exhalation. This double breathing relieves birds of shortness of breath: the faster they fly, the more they breathe. Increase the energy of the bird in flight. Working muscles and organs require a lot of energy. Air sacs are located between organs, under the skin, and even inside hollow bones, reducing the density of the bird, making it lighter. Air bags also protect internal organs from overheating during the flight.
excretory system: (slide 14) bean-shaped kidneys, the formed liquid decay products flow down the ureters into the cloaca and, together with the feces, are excreted. Birds do not have a bladder. What is it connected with? (facilitates birds in flight)
Nervous system (slide15) birds are well developed compared to reptiles. Let's note which departments are developed better. (cerebellum, anterior hemispheres)
Why do you think? What is the cerebellum responsible for? - cerebellum responsible for the coordination of movements. Birds in flight have to maneuver a lot in search of food, dodge predators.
Large hemispheres much larger, especially the visual lobes of the brain.
Sense Organs - Vision in birds is very good, especially in birds of prey. Color vision.
Hearing is well developed. The sense of smell in birds is less developed.
The large brain of birds testifies to their high development: they have complex behavior (flights, care for offspring, etc.), they easily learn new things, remember. slide 16
Anchoring . (slide 19) Thus, we learned that the internal structure of birds is much more complicated than that of reptiles. Features of the external and internal structure of birds indicate the adaptability of birds to life in flight.
Lesson conclusion: Can a bird be called an aircraft? Yes. Birds are perfect aircraft.
Birds are perfectly adapted to flight, and today we tried to prove it.
View slide 20. When further study animals we learn about another group of flying animals.
Slide 21 Reflection on the lesson.
Grading a lesson.
Houses §42, table.
Complete the table you started in the previous lesson. Describe the characteristics of bird adaptations for flight.
In the lesson, you can use the DER - presentation, microfilm from the educational digital manual 1C: Laboratory "Why do we breathe"