The skeleton of the trunk mainly consists of spinal column made of a number of bony segments called vertebrae to which the head, the thoracic cavity and the pelvic bones are connected. The spinal column consists of 26 spinal column bones.
The human vertebrae are divided into differentiated groups. The seven most superior of them are the vertebrae called the cervical vertebrae. The first cervical vertebra is the atlas. The second vertebra is called the axis.
Inferior to the cervical vertebrae are twelve thoracic vertebrae. There is one rib connected to each thoracic vertebrae, making 12 pairs of ribs. Most of the rib pairs come together ventrally and join a flat bone called the sternum.
The first pairs or ribs are short. All seven pairs join the sternum directly and are sometimes called the «true ribs». Pairs 8, 9, 10 are «fal-se ribs». The eleventh and twelfth pairs of ribs are the «floating ribs».
Inferior to the thoracic vertebrae are five lumbar vertebrae. The lumbar vertebrae are the largest and the heaviest of the spinal column. Inferior to the lumbar vertebrae are five sacral vertebrae forming a strong bone in adults. The most inferior group of vertebrae are four small vertebrae forming together the соссух.
The vertebral column is not made up of bone alone. It also has cartilages.
New words
skeleton – скелет
make up – составлять
weight – вес
trunk – туловище
mainly – главным образом
thoracic cavity – грудная впадина
axis – ось
spinal column – позвоночник
inferior – низший
rib – ребро
pair – пара
sacral – сакральный
соссух – копчик
floating – плавающий
forming – формирующий
cartilage – хрящ
Если после конструкции there is (there are) стоит неисчисляе-мое существительное во множественном числе, вместо опущенного неопределенного артикля часто (не обязательно) употребляется слово «some».
Вставьте артикль, где необходимо.
1. There is… sofa in… corner of… room.
2. There are… cushions on… sofa
3. There are… books on… shelf. Give me… book, please.
4. Look into… refrigerator. What can you see on… shelves?
5. There is… butter in… butter-dish.
6. There is. sausage, but there is no… cheese.
7. There are… eggs,… apples.
8. There is… orange,… lemon, and… some jam in… little vase.
9. There is juice in this… cup. May I drink… juice?
10. There are… girls in… yard, but I can see no… boys. Where are… boys?
11… boys are playing football at… stadium.
12. I have. colour TV-set… TV-set is on… little table in… corner of… room.
13. There is… book,… pen, and… paper on my… writing-desk.
14. My… brother is… teacher. He works at… school.
15. He has… very good books. His… books are in… big bookcase.
16. There is… tea in my… glass. There is no… tea in my… friend's… glass.
17. His… glass is empty.
18. Where is… coffee-table in your… room? -… coffee-table is in… front of… sofa
19. There is… cup on… coffee-table and… newspa pers.
20. There is. coffee in… cup.
Answer the questions.
1. What do the bones of our body make up?
2. How many per cents does the skeleton form?
3. What does the skeleton of the trunk mainly consist of?
4. How many bones does the spinal column consist of?
5. What groups are the human vertebrae divided into?
6. How many groups are the most superior?
7. How is the first cervical vertebra called?
8. Are the first pairs or ribs short?
9. How is the second vertebra called?
10. What forms the соссух?
Make the sentences of your own using the new words (10 sentences).
Find the definite and indefinite articles in the text.
ЛЕКЦИЯ № 10. Muscles
Muscles are the active part of the motor apparatus; their contraction produces various movements.
The muscles may be divided from a physiological standpoint into two classes: the voluntary muscles, which are under the control of the will, and the involuntary muscles, which are not.
All muscular tissues are controlled by the nervous system. The involuntary muscles are controlled by a specialized part of the nervous system.
When muscular tissue is examined under the microscope, it is seen to be made up of small, elongated threadlike cells, which arc called muscle fibres, and which are bound into bundles by connective tissue.
There are three varieties of muscle fibres:
1) striated muscle fibres, which occur in voluntary muscles;
2) unstriated muscles which bring about movements in the internal organs;
3) cardiac or heart fibres, which are striated like (1), but are otherwise different. Both unstriated and cardiac muscles are involuntary. All living cells can move to some degree, but this ability is highly developed in muscles. Muscle tissue comprises about 40% of human weight. Muscle consists of threads, or muscle fibers, supported by connective tissue, which act by fiber contraction: the fibers can shorten to two – thirds of their resting length. There are two types of muscles smooth and striated. Smooth, or «involuntary» muscles are found in the walls of all the hollow organs and tubes of the body, such as blood vessels and intestines. These react slowly to stimuli from the autono-mic nervous system. The striated, or «voluntary» muscles of the body mostly attach to the bones and move the skeleton. Under the microscope their fibres have a cross – striped appearance. Striated muscle is capable of fast contractions. The heart wall is made up of special type of striated muscle fibres called cardiac muscle. Muscles vary greatly in structure and function in different organs and animals: some invertebrates have only smooth muscles, while all the arthropods have only striated muscles. The body is composed of about 600 skeletal muscles. In the adult about 35-40% of the body weight is formed by the muscles. According to the basic part of the skeleton all the muscles are divided into the muscles of the trunk, head and extremities.
According to the form all the muscles are traditionally divided into three basic groups: long, short and wide muscles. Long muscles compose the free parts of the extremities. The wide muscles form the walls of the body cavities. Some short muscles, of which stapedus is the smallest muscle in the human body, form facial musculature.
Some muscles are called according to the structure of their fibres, for example radiated muscles; others according to their uses, for example extensors or according to their directions, for example, – oblique. The muscles are formed by a mass of muscle cells. The muscle fibres are connected together by connective tissue. There are many blood vessels and nerves in the muscles.
Great research work was carried out by many scientists to determine the functions of the muscles. Three basic methods of study were used: experimental work on animals, the study of the muscles on a living human body and on the cadavers. Their work helped to establish that the muscles were the active agents of motion and contraction.
New words
muscles – мышцы
active – активный
part – часть
motor apparatus – двигательный аппарат
various – различный
movement – движение
elongated – удлиненный
threadlike – нитевидный
to be bound – быть связанным
some – некоторый
degree – степень