Иностранный язык (английский). Учебное пособие
.pdfbands that rotate and crush food by shifting the food from one area to the next within the gizzard. The gizzard of some species contains small pieces of grit or stone swallowed by the bird to aid in the grinding process of digestion, serving the function of mammalian or reptilian teeth. The use of gizzard stones is a similarity between birds and dinosaurs, which left gizzard stones called gastroliths as trace fossils. Most birds drink by repeatedly raising their heads after filling their mouths to allow the liquid to flow by gravity.
Skeletal system consists of skull, cervical vertebrae, furcula, and coracoid, uncinate processes of ribs, patella, tarsometatarsus, digits, tibia, femur, ischium, pubis, illium, caudal vertebrae, pygostyle, sacrum, scapula, lumbar vertebrae, humerus, ulna, radius, carpus, metacarpus and digits. The bird skeleton is highly adapted for flight. It is extremely lightweight but strong enough to withstand the stresses of taking off, flying, and landing, birds usually have a smaller number of bones than other vertebrates. Birds also lack teeth or even a true jaw, instead having evolved a beak, which is far more lightweight. Birds have many bones that are hollow with criss-crossing struts. Birds also have a highly flexible neck consisting of 13–25 vertebrae. Birds are the only vertebrate animals to have a fused collarbone or a sternum or breastbone. The keel of the sternum serves as an attachment site for the muscles used for flight, or similarly for swimming in penguins. It is noted that swimming birds have a wide sternum, while walking birds had a long or high sternum while flying birds have the width and height nearly equal.
Skeletal composition. The skull consists of five major bones: the frontal (top of head), parietal (back of head), premaxillary and nasal (top beak), and the mandible (bottom beak).
The vertebral column consists of vertebrae, and is divided into three sections: cervical (neck), sacrum, and pygostyle (tail). The chest consists of the furcula (wishbone) and coracoid (collar bone), together with the scapula, forms the pectoral girdle. The side of the chest is formed by the ribs, which meet at the sternum (mid-line of the chest). The shoulder consists of the scapula (shoulder blade), coracoid, and humerus (upper arm). The humerus joins the radius and ulna (forearm) to form the elbow. The carpus and metacarpus form the “wrist” and “hand” of the bird and the digits (fingers) are fused together. The
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bones in the wing are extremely light so that the bird can fly more easily.
The hips consist of the pelvis which includes three major bones: illium (top of the hip), ischium (sides of hip), and pubis (front of the hip). These are fused into one the innominate bone. Innominate bones allow birds to lay eggs. They meet at the acetabulum and articulate with the femur, which is the first bone of the hind limb.
Structure of the leg. The upper leg consists of the femur. At the knee joint, the femur connects to the tibiotarsus (shin) and fibula (side of lower leg). The leg bones of birds are the heaviest, contributing to a low center of gravity.
Muscular system. Most birds have approximately 175 different muscles. The largest muscles in the bird are the pectorals, or the breast muscles, which control the wings and make up about 15–25 % of a flighted bird’s body weight. They provide the powerful wing stroke essential for flight. The muscle ventral (underneath) to the pectorals is the supracoracoideus. It raises the wing between wingbeats. The skin muscles help a bird in its flight by adjusting the feathers, which are attached to the skin muscle and help the bird in its flight maneuvers. There are only a few muscles in the trunk and the tail, but they are very strong and are essential for the bird. The pygostyle controls all the movement in the tail and controls the feathers in the tail. This gives the tail a larger surface area which helps keep the bird in the air.
Head. Skull of a bird. Birds have acute eyesight thanks to higher densities of photoreceptors in the retina, a high number of optic nerves, a second set of eye muscles not found in other animals, and, in some cases, an indented fovea which magnifies the central part of the visual field. Many species have two foveas in each eye. Many birds can detect polarized light. The eye occupies a considerable part of the skull and is surrounded by a sclerotic eye-ring, a ring of tiny bones that surround the eye. The bills of many waders have Herbst corpuscles which help them detect prey hidden under wet sand using minute pressure differences in the water. Birds have a large brain to body mass ratio. This is reflected in the advanced and complex bird intelligence. The region between the eye and bill on the side of a bird's head is called the lore. This region is sometimes featherless, and the skin may be tinted, as in many species of the cormorant family.
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Reproduction. Fledgling. Although most male birds have no external sex organs, the male does have two testes which become hundreds of times larger during the breeding season to produce sperm. The female's ovaries also become larger, although only the left ovary usually functions. However, if the left ovary is damaged by infection or other problems, the right ovary will try to function. In the males of species without a phallus, sperm is stored in the seminal glomera within the cloacal protuberance prior to copulation. During copulation, the female moves her tail to the side and the male either mounts the female from behind or in front (in the stitch bird), or moves very close to her. The cloacae then touch, so that the sperm can enter the female's reproductive tract. This can happen very fast, sometimes in less than half a second. The sperm is stored in the female's sperm storage tubules for a week to a year, depending on the species. Then, eggs will be fertilized individually as they leave the ovaries, before being laid by the female. The eggs continue their development outside the female body.
Scales. The scales of birds are composed of the same keratin as beaks, claws, and spurs. They are found mainly on the toes and metatarsus, but may be found further up on the ankle in some birds. Feathers can be intermixed with scales on some birds' feet. Feather follicles can lie between scales or even directly beneath them, in the deeper dermis layer of the skin.
Vocabulary list
external [eks'tə:nl] – наружный, внешний beak [bi:k] – клюв
iris ['aiəris] – радужка, радужная оболочка (глаза) mantle ['mæntl] – кора головного мозга
covert – оперение
scapula ['skæpjulə] – лопатка
rump – ягодичная область, крестец
vent ['vent] – отверстие (вход в полость)
tibio-tarsal – большая берцовая предплюсневая кость tarsus ['ta:səs] – предплюсна
tibia ['tibiə] – большеберцовая кость
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flank ['flænk] – бок
breast ['brest] – грудь, грудная клетка wattle ['wætl] – сережка (у птиц) inhalation ["inhə'lei∫ən] – вдыхание exhalation ["ekshə'lei∫ən] – выдыхание
cervical air sac [sə:'vaikəl εə sæk] – цервикальный альвеолярный мешочек
clavicle air sac ['klævikl εə sæk] – ключичный альвеолярный мешочек
cranial ['kreinjəl] – краниальный, черепной thoracic air sac – грудной альвеолярный мешочек caudal ['kɒ:dəl] – каудальный
anterior air sac [a:n'tiəriə εə sæk] - передний альвеолярный мешочек posterior air sac – задний альвеолярный мешочек
four-chambered – четырехкамерный
alimentary ["eli'mentəri] – пищевой, пищеварительный papilla [pə'pilə] – сосок, сосочек, бугорок
crop – зоб
ventriculus L – желудок, желудочек gizzard ['gizəd] – второй желудок band [bænd] – связка, пучок волокон grit [grift] – песок, гравий
gastrolith – безоар (инородное тело в желудке), желудочный камень
fossil – ископаемый, окаменелость furcula L. – дужка (грудная кость птицы) coracoid L. – клювовидный
uncinate process – крючковидный отросток
patella [pə'telə] – надколенник, (над)коленная чашечка tarsometatarsus L. ['ta:səu,metə'ta:səs] – предплюсна digit – палец
ischium L. – седалишная кость pubis L. – лобок, лобковая кость ilium L. – подвздошная кость pygostyle ['pigəυ'stail] – хвост sacrum ['seikrəm] – крестец
lumbar vertebrae – поясничный позвонок
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humerus L. – плечевая кость ulna – локоть
radius ['reidjəs] – лучевая кость carpus ['ka:pəs] – запястье
evolve – эволюционировать, развиваться hollow – углубление, впадина, полость criss-crossing – перекрещивающийся
strut – важная или неестественная походка flexible neck ['fleksəbl nek] – гибкая шея collar bone – дужка (грудная кость птицы) sternum ['stə:nəm] – грудина
breastbone [brest boun] – грудина
parietal [pə'raiitl] – париетальный, теменной premaxillary bone [pri:'mæksiləri] – резцовая кость mandible ['mændibl] – нижняя челюсть
vertebral column – позвоночник, позвоночный столб
cervical [sə:'vaikəl] – затылочный шейный цервикальный отдел pectoral girdle ['pektərəl gə:dl] – грудной пояс
hip [hip] – бедро
innominate bone – тазовая кость acetabulum L. – вертлужная впадина femur [fi:mə] – бедро
hind limb [haind li:m] – задняя конечность knee joint – коленный сустав
fibula ['fibjulə] – малоберцовая кость breast muscle – грудная мышца
ventral ['ventrəl] – вентральный, брюшной supracoracoid L. – надклювовидный отросток (лопатки) retina ['retinə] – сетчатка
optic – глазной, зрительный fovea – ямка
lore – уздечка (у птиц) fledgling – оперение ovary ['əuveri] – яичник
phallus ['fæləs] – половой бугорок glomera – сперма, семенная жидкость cloacal – клоачный
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tubule ['tju:bju:l] – трубочка, каналец scale ['skeil] – чешуйка
keratin ['kerətin] – кератин, роговое вещество claw – коготь
spur – костная шпора
ankle [æŋkl] – голеностопный сустав, лодыжка
I. Answer the following questions.
1.What is the general plan of the structure of respiratory system?
2.What is the skeleton composed of?
3.What does the skull contain?
4.What is the external covering of the body?
5.How is sound produced?
6.What heart do the birds have?
7.What does the digestive system look like?
8.How many stomachs do the birds have?
9.What happens with the food in the stomachs?
10.What is the skeleton composed of?
11.How many muscles do the birds have? What muscles can you name?
12.What do we call the bones of the head?
13.What are the organs of reproduction?
14.What is the structure of the legs?
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The anatomy of the pig
Circulatory system. Pigs, like all mammals, have a four chambered heart. Blood enters the right atrium via the superior and inferior vena cava. The blood is then pumped into the right ventricle from where it is pumped to the lungs to be oxygenated via the pulmonary arteries. Oxygen-rich blood is then pumped through the left atrium and into the left ventricle. Location of the fetal heart will show that the walls of the left ventricle are thicker than those of the other chambers. This is due to fact that the muscle of the left ventricle must be strong enough to pump oxygen-rich blood throughout the body.
The aortic arch of a fetal pig has two arteries attached to it, the brachiocephalic artery and the subclavian artery. As the aorta descends, it splits into two large iliac arteries. An umbilical artery branches near the base of each iliac artery. The umbilical arteries run through the umbilical cord, carrying blood to the maternal placenta where it becomes oxygenated, nutrient-rich, and free of waste. This oxygenated, nutrient-rich blood is then returned to the liver of the fetus via the umbilical vein. There are only a few differences between the circulatory system of an adult pig and a fetal pig, besides from the umbilical arteries and vein. There is a shunt between the wall of the right and left atrium called the foramen ovale. This allows blood to pass directly from the right to left atrium. There is also the ductus arterius which allows blood from the right atrium to be diverted to the aortic arch. Both of these shunts close a few minutes after birth.
Digestive system. The monogastric digestive system of the fetal pig harbors many similarities with many other mammals. The fetal pig's digestive organs are well developed before birth, although it does not ingest food. These organs include the esophagus, stomach, small and large intestines. Mesenteries serve to connect the organs of the fetal pig together. In order for digestion to occur, the fetal pig would have to ingest food. Instead, it gains much needed nutrition from the mother pig via the umbilical cord. In the adult pig, food will follow the general flow through the esophagus, which can be located behind the tracheae. From the oral cavity, the esophagus leads to the stomach, small intestine, and large intestine. Other organs developing during
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fetal pig development such as the gallbladder, pancreas and spleen are all critical in contributing to the overall flow of the digestive system.
After being digested and absorbed, the food follows through the large intestine and is excreted through the rectum and anus. In the fetal pig however, the metabolic wastes are sent back to the mother through the umbilical cord where the mother excretes the wastes. Other remaining wastes remain in the fetal pig until birth. The oral cavity of the fetal pig begins developing before birth. The tongue's taste buds, located in the enlarged papillae, facilitate food handling after birth. These taste buds develop during fetal development. Adult pigs have up to 15,000 taste buds, a much larger number than the average human tongue, which has 9,000. The dental anatomy of the fetal pig shows differences from adult pigs. The fetal pig develops primary teeth (which are later replaced with permanent teeth). Some may erupt during fetal stage, which is why some of the pigs that are/will be dissected show evidence of teeth. Depending on the age of the fetal pig, it is natural to see eruptions of third incisor and canine in the fetal pig. Because the fetal pigs were still in the mother’s uterus, teeth will still form which supports reasons for hollow unerupted teeth that may be seen during the dissection. Similar to human dental anatomy, the overall dental anatomy of the pig consists of incisors, canines, premolars, and molars. Exploring the dental anatomy even further, piglets can have 28th teeth total and adult pigs can have 44 teeth total. If you would like to compare this to the dental anatomy of a human, there are 20 primary teeth and 28–30 permanent teeth.
Urogenital system of a female pig. The fetal pig urogenital system is similar to the adult pig's system with the exception of the reproductive organs. The fetal pig urinary track is relatively developed and easy to locate during dissection. The kidneys are located behind the abdominal organs and are partially embedded into the dorsal body wall by the spine. The ureters carry the urine to the urinary bladder, the large sack-like organ by the umbilical artery and vein, to the urethra. From there, the urine can be excreted. To externally determine if the fetal pig is a female, there will be a fleshy protrusion ventral near the anus called the genital papilla.
Reproductive system. The female's internal reproductive system is located below the kidneys. The two sac-like organs attached
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to the coil-like fallopian tubes are the ovaries. The uterus, which becomes the vagina, is located where the fallopian tubes meet. This system can be difficult to find as it is small as well as extremely dorsal and posterior to the other systems.
Male: to externally determine if the fetal pig is male, look for the urogenital opening located behind the umbilical cord. Also note the swelling behind the hind legs of the fetal pig. This will be the scrotum. The male's internal reproductive system has two scrotal sacs, which depending on the age of the fetal pig may or may not have developed testes. The epididymis coil on the testes connects to the vas deferens. The vas deferens crosses over the ureter and enters the urethra, which then connects to the penis located just posterior to the skin. Similar to the female system, the male system may also be difficult to identify all parts. If the fetal pig is indeed male, take caution to not cut very deep into the scrotum when dissecting.
Vocabulary list
atrium pl. atria ['ætriəm] – предсердие
superior vena cava [sju:'piəriə 'vi:nə 'kævə] – верхняя полая вена inferior vena cava [in'fiəriə 'vi:nə 'kævə] – нижняя полая вена aortic arch – дуга аорты
subclavian artery – подключичная артерия
iliac artery ['iliæk 'a:təri] – подвздошная артерия umbilical artery – пупочная аорта
maternal placenta [mə'tə:nl plə'sentə] – материнская плацента fetus ['fi:təs] – плод
foramen ovale – овальное отверстие
ductus artery – артерия семявыносящего протока shunt – шунт
monogastric – одножелудочный mesentery ['mesəntəri] – брыжейка rectum ['rektəm] – прямая кишка metabolic – метаболический
taste bud – вкусовая почка
permanent teeth ['pə:mənənt ti:θ] – постоянные зубы unerupted teeth – непрорезанные зубы
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dissection [di'sek∫n] – рассечение protrusion – протрузия
ventral ['ventrəl] – брюшной papilla – сосочек
scrotum ['skrəutəm] – мошонка epididymis ['epi'didimis] – эпидидимис
vas deferens [væs'defərəns] – семявыносящий проток
I. Answer the following questions.
1.What peculiarities of the structure of сirculatory system do you know?
What is its function?
2.What organs form the digestive system and where are they contained?
What are the functions of the organs of digestion?
3.What is urogenital system? What are the excretory organs? What functions have they got?
4.What is reproductive system? What are the reproductive organs? What functions have they got?
The anatomy of the cattle
Cattle are raised as livestock for meat (beef and veal), as dairy animals for milk and other dairy products, and as draft animals (pulling carts, plows and the like). Other products include leather and dung for manure or fuel. In some countries such, as India, cattle are sacred. It is estimated that there are 1.3 billion cattle in the world today. Cattle have one stomach with four compartments. They are rumen, reticulum, omasum, and abomasum, with the rumen being the largest compartment. The reticulum, the smallest compartment, is known as the “honey comb”.
Cattle sometimes consume metal objects which are deposited in the reticulum and irrigation from the metal objects causing hardware disease. The omasum’s main function is to absorb water and nutrients from the digestible feed. The omasum is known as the “many plies”.
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