Text A. 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 sixth costal cartilages. The weight of the heart is about 300 grams(gr) in the male and about 220 gr in the female.

The heart consist of two separate 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 than those of the right one. The right ventricle is triangular in form and has thick walls. The right ventricle is in the anterior part of the heart. The left ventricle is longer and more conical than the right one. The walls of the left ventricle are three times as thick as the walls of the right one. The valves are located at the entrance and exit of each ventricle.

The muscular structure of the heart consists of fibrous bands divided into two groups – the first ones are the fibrous bands of the atria and the second ones are the fibrous bands of the ventricles.

The vascular system consist 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.

Most of the arteries are composed of three coats. The arteries dilate and contract simultaneously with the action of the heart.

 

Text B. The Valves of the Heart

In the left chamber the atrium and ventricle are separated by the mitral [´maitrəl] valve. In the right chamber the atrium and ventricle are separated by the tricuspid [trai’kλspid] valve.

At the point of origin of the aorta in the left ventricle another valve is located. This valve is called the semilunar[,semi´lu:nə] valve of the aorta.

At the point of origin of the pulmonary artery in the right ventricle the fourth valve is located. It is called the semilunar valve of the pulmonary artery.

B. Training lexical material and understanding new information. Fulfilling exercises after reading and translating the text.

Reading, speaking

Remember the facts.

The Heart..........

 

· Is a muscle about the size of your fist

· Weights approximately one pound

· Is located behind and slightly to the left of the breastbone

· Pumps about 5 quarts (4.7 liters) of blood every minute

The function of the heart is to circulate blood throughout the body by:

 

· Pumping blood through the lungs removes carbon dioxide and refreshes the blood with oxygen

· The oxygenated blood is pumped to the body to provide oxygen and nutrients and to remove waste products.

· The coronary arteries are the blood vessels that supply blood and oxygen to the heart muscle.

 

Blood Supply to the Heart

2 coronary arteries branch from the main aorta just above the aortic valve. “No larger than drinking straws, they divide and encircle the heart to cover its surface with a lacy network that reminded physicians of a slightly crooked crown (coronary comes from the Latin coronarius, belonging to a crown or wreath). They carry out about 130 gallons of blood through the heart muscle daily.”

 

Reading

 

3. Read and translate the following words and word combinations.

a heart, a muscular organ, a pericardium, the base of the heart, an apex, an interspace, costal cartilages, separate chambers, an atrium, a ventricle, atrioventricular valves, the right atrium, the left atrium, the right ventricle, the left ventricle, the anterior part, the posterior part.

Reading and speaking

4. Quote the sentences in which these words and word combinations are used in the text:

heart, vascular system, atrium, ventricle, muscular structure, fibrous bands, arteries, veins, capillaries, general system, systemic vessels, pulmonary system, portal system

 

Reading, speaking, writing