XI. Выберите правильный ответ на вопрос:

1. What did the scientists find out?

a. The scientists find out the total blood weight.

b. The scientists found out the total blood weight.

c. The scientists have found out the total blood weight.

2. What is the rate of the heartbeat regulated by?

a. The rate of the heartbeat was regulated by two groups of nerve fibers.

b. The rate of the heartbeat has regulated by two groups of nerve fibers.

c. The rate of the heartbeat is regulated by two groups of nerve fibers.

3. What has the physician used?

a. The physician has already used the new method of treatment.

b. The physician is already used the new method of treatment.

c. The physician already used the new method of treatment.

4. How many phases does each cardiac cycle consist of?

a. Each cardiac cycle consist of three phases.

b. Each cardiac cycle is consist of three phases.

c. Each cardiac cycle consists of three phases.

XII. Переведите предложения, обращая внимания на выделенные наречия:

1. Я часто посылаю письма своим родителям. 2. Я только что отправил письмо своим родителям. 3. Вчера я отправил письмо своим родителям. 4. Вчера я отправил письмо своим родителям до того, как пошел на лекцию. 5. Я отправлю письмо своим родителям в следующий понедельник. 6 Я отправлю письмо своим родителям к концу недели. 7. Сейчас я отправляю не письмо, а фотографии.

XIII. Прочтите и переведите текст:

Text A. WORK OF THE HUMAN HEART

The human heart contracts from the first moment of life until the last one. The contractions of the heart pump the blood through the arteries to all parts of the body. Scientists have determined that the total weight of the blood pumped by the heart daily is about ten tons. The rate of heart contractions is regulated by two groups of nerve fibers. It varies in different persons and at different age.

Physiologists have determined that in the adult the heart makes from 60 to 80 beats per minute. In children the rate of heartbeat is much higher. Research work of many scientists has helped to determine that the rate of heartbeat increases depending on different emotions.

Each beat of the heart is followed by a period of rest of the cardiac muscle. Each wave of contraction and a period of rest following it compose a cardiac cycle. Each cardiac cycle consists of three phases: physiologists have called the first phase of short contraction of both atria – the atrial systole. They have called the second phase of a more prolonged contraction of both ventricles – the ventricular systole. The period of rest of the cardiac muscle is called – the diastole.

During the systole of the ventricle the blood is pumped from the right ventricle into the pulmonary artery. When the right ventricle has pumped the venous blood into the pulmonary artery it enters the pulmonary circulation. The blood is brought to the lungs. In the lungs the venous blood discharges out carbon dioxide. When the blood has discharged out carbon dioxide it takes in oxygen in the lungs. The blood which has become oxygenated passes from the pulmonary veins to the left atrium of the heart.

Under the pressure of the left atrium the arterial blood which the pulmonary veins have brought to the heart is pumped into the left ventricle. During the prolonged contraction of the left ventricle the arterial blood is pumped into the aorta – the main artery of the vascular system. When the left ventricle has pumped the arterial blood into the aorta it is carried through the arteries to all the parts of the body.

Prolonged research work of many physiologists has given the possibility to estimate the role of the ventricles which serve as the main pump. The atria act as receiving chambers.

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