XI. Раскройте скобки, употребив сказуемое в Simple или Continuous:

1. The students ( to work) in the laboratory from 9 till 11 yesterday.

2. When we (to come) they (to classify) the bones of the upper extremities.

3. The walls of the blood vessels (to expand) when they ( to respond) to some

chemicals in the blood.

4. We ( to discuss) the characteristic features of cardiac muscles now.

5. A positive test ( to mean) the presence of bacteria in the blood.

6. The students ( to read) text when the teacher ( to enter) the classroom.

7. Voluntary muscles ( to control) the beating of the blood.

8. Many scientists ( to carry out) great research work.

9. You can’t see him now because he (to perform) the operation.

10. Next year students (to listen) to the lectures on therapy.

XII. Прочтите текст и найдите в нем эквиваленты следующих словосочетаний, переведите этот текст:

согласно одной теории, происходит от латинского слова, греческое выражение, двигательный аппарат, действие температуры, поворот головы, изменения окружающей среды, они находятся под контролем, характерная черта, не имеет ни начала ни конца, огромная сеть

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.

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