Text A. Types of muscles

The word “muscle”, according to one theory, comes from a Latin word that means “little mouse”: when a man’s muscles are contracting they look as if a little mouse runs about under the skin. According to another theory the word “muscle” comes from a Greek expression that means “to enclose”, that is layers of muscles enclose the body. We know that the muscles constitute about 50 per cent of the total body weight.

Muscles are the active part of the motor apparatus. Their contractions are producing various movements when they are active. Functionally all muscles are divided into two groups: voluntary and involuntary muscles.

There are three main types of muscular tissue that we identify and classify on the basis of its structure and functions:

1. smooth or visceral muscle;

2. striated or skeletal muscle;

3. cardiac muscle.

Smooth muscles can contract slowly. They make up the walls of the internal organs. They include all the muscles of the head, trunk and extremities as well as the muscles of some internal organs. Since we identify the internal organs as viscera, we sometimes call smooth muscles visceral muscles. The walls of the blood vessels are contracting when they respond to some chemicals in the blood or to the effect of temperature. For this reason we may call them involuntary muscles. Smooth muscle tissue consists of long cells. Smooth muscle fibers are bound into bundles by connective tissue which contain blood vessels and nerves. There are more than 400 skeletal muscles in the human body.

Striated muscle tissue consists of large fibers in the form of bundles. These muscles are necessary for manipulation of the bones of the skeleton for walking, running, turning the head and so on. That’s why we sometimes call them skeletal muscles. This type of muscular tissue includes the large muscle masses of the body, the muscles of the arms, legs, back, etc. It includes all the muscles which must respond quickly to changes in the environment. For this reason we call striated muscles voluntary muscles.

Cardiac muscle is a cross between the previous two. A characteristic feature of cardiac muscle is that fibers have neither a beginning nor an end. In other words the heart is simply a huge net of muscles in which all elements are continuous with each other. Cardiac muscles have the strength of contraction of the skeletal muscles. They are under complete involuntary control.

TASKS

I. Complete the following sentences:

1. Functionally all muscles can be divided into … a. three groups

b. two groups

c. numerous groups

2. Smooth muscles make up … a. free parts of the extremities

b. the walls of the internal organs

c. the main parts of the trunk

3. Striated muscles are necessary for … a. motion and contraction

b. formation of fibrous bundles

c. manipulation of the bones of the skeleton

4. Cardiac muscles are … a. under involuntary control

b. under voluntary control

II. Make up questions to the underlined words:

1. Muscles are the active part of the motor apparatus.

2. Their contractions are producing various movements.

3. Functionally all muscles are divided into two groups.

4. Smooth muscles make up the walls of the internal organs.

5. Smooth muscles can contract slowly.

6. Striated muscle tissue includes the large muscular masses of the body.

III. Express your agreement or disagreement with the following statements:

1.Theword muscle is an English word.

2. Muscles constitute about 50 per cent of the total body weight.

3. Muscles are the active part of the nervous system.

4. There are five main types of muscular tissue on the basis of its structure and

functions.

5. Smooth muscles make up the walls of the internal organs.

6. Striated muscles are called involuntary or visceral muscles.

7. There are more than 400 skeletal muscles in the human body.

IV. Answer the questions:

1. What is the origin of the word muscle?

2. What two groups of muscles do you know?

3. How many types of muscular tissue can we identify on the basis of structure and

functions?

4. What are the other names for smooth muscles?

5. Why can we call them visceral muscles?

6. Why can we call them involuntary muscles?

7. What are the other names for striated muscles?

8. Why can we call them skeletal muscles?

9. Why can we call them voluntary muscles?

V. Translate the sentences into English:

1. В теле человека примерно 400 скелетных мышц. 2. По строению и функциям мышцы можно разделить на три основные группы. 3. Соединительная ткань гладких мышц содержит нервы и кровеносные сосуды. 4. Поперечно-полосатые мышцы иначе можно назвать скелетными мышцами. 5. Они реагируют на изменения в окружающей среде. 6. Волокна сердечной мышцы непрерывны. 7. Сердце – это огромная сеть мышц.

VI. Learn the following words:

born [bLn]- рожденный

to be born - родиться

degree [di’grJ]– (ученая) степень; градус

to receive [ri’sJv]– получать, принимать

strong – сильный, крепкий, здоровый

surface [‘sWfis] - поверхность

point [point]– место. точка

origin [‘OriGin] – начало, источник, происхождение

finding [‘fQindiN]- находка

findings – данные, результаты

ending - окончание

abdomen [‘qebdqmqn] – живот, брюшная полость

to restore [ri’stL] - восстанавливать

condition [kqn’diSn]– состояние; условие

band - пучок

VII. Translate the sentences paying attention to the underlined words:

1. The bands of muscular fibers may be long or short. 2. The human leg has a large surface. 3. Show us in the picture the point of connection of the rib and the breastbone. 4. The origin of some diseases is not well studied. 5 He is the Ukranian by origin. 6 He received the degree of Doctor of Medicine at the age of 35. 7. The patient’s temperature was 38.5 degrees C. 8. It is impossible to work under such condition s. 9. The patient’s condition was not very bad. 10. The patient’s health was restored after the course of treatment.

VIII. Translate the following word combinations:

total body weight, under the skin, smooth muscle fibers, characteristic feature, to contain blood vessels and nerves, in the form of bundles, changes in the environment, a huge net of muscles, the strength of contraction, the surface of the cells, valuable method of treatment, connective tissue, the bands of muscular fibers, nerve endings, the point of origin, to receive important findings, the upper part of the abdomen, to restore health, patient’s condition

IX. Translate the text using a dictionary: