The Heart and the Vascular System

The heart is an inner hollow muscular organ placed within the chest and included in the pericardium. The base of the heart is against the third rib. Its apex is against the interspace between the fifth and the sixth costal cartilages. The weight of the heart is about 300 grams (g) in the male and about 220 g in the female.

The heart consists of two chambers divided by the septum. Each of the chambers has two connected parts: the atrium and the ventricle. The atrioventricular valves separate the atria from the ventricles.

The right atrium is larger than the left one, but the walls of the left atrium are thicker. The left ventricle is longer and more conical and its walls are three times thicker than in the right one.

The muscular structure of the heart consists of fibrous bands of the atria and the fibrous bands of the ventricles. The vascular system consists of three groups of vessels – arteries, veins and capillaries. The vessels carrying blood to and from the tissues of the body compose the general system. They are called the systemic vessels. The pulmonary system is formed by the vessels carrying blood to and from the lungs. The portal system is formed by the veins passing to the liver.

Задание 4. Ответьте на вопросы:

1) What is the heart?

2) Where are the base and the apex situated?

3) What is the weight of the heart?

4) What main parts does the heart consist of?

5) Is there any difference between the atria or between the ventricles?

6) What fibrous bands form the muscular structure of the heart?

7) Does the vascular system consist of three groups of vessels? What are they?

II. Работа над грамматикой. (45 мин) Passive Voice

Задание 1. Прочтите § 14 Грамматического справочника, стр 290-291. Повторите форму Пассивного залога времён Simple.

Задание 2. Переведите предложения, укажите видо-временную форму сказуемого:

1) These operations are performed by me.