Exercise 6. Read and translate the text:

The cardio-vascular system

The cardiovascular system is sometimes called the circulatory system. It consists of the heart, which is a muscular pump and a system of vessels such as arteries, veins, and capillaries.This system is responsible for blood transportation. The cardiovascular system moves blood throughout the body that transports oxygen and nutrients to the cells and removescarbon dioxide and other wastes from the body. The word cardiovascularis composed of two parts: the Greek word kardia which means "heart" and the Latin word vasculum which means "small vessel."

The heart is the muscular pump in the centre of the chest that beats continuously and rhythmically to send blood to the lungs and the rest of the body. It is located on the diaphragm between the lower borders of the lungs, occupying the middle of the mediastinum. It is covered ventrally by the sternum and the adjoining parts from the third to the sixth costal cartilages. The weight of the heart in men is approximately 300 g and in women 260 g. Much of the heart consists of myocardium, a special type of muscle. The heart muscle is supplied with oxygen and nutrients by two coronary arteries.

The internal surface of the heart is lined with a smooth membrane, called endocardium, and the entire heart is enclosed in a tough, membranous bag, the pericardium. A thick central muscular wall, the septum, divides the heart cavity into right and left halves. Each half consists of an upper chamber, called an atrium, and a larger lower chamber, called a ventricle. The right atrium receives deoxygenated blood from the entire body via 2 large veins called the venae cavae. This blood is transferred to the right ventricle and pumped to the lungs via the pulmonary artery to be oxygenated and to lose carbon dioxide. The left atrium of the heart receives oxygenated blood from the lungs (via the pulmonary veins); this blood is transferred to the left ventricle and then pumped to all tissues in the body.

The valves of the heart include the tricuspid valve, the bicuspid (mitral) valve, the semilunar aortic valve, and the semilunar pulmonary valve. The sinoatrial node in the right atrium of the heart initiates the cardiac impulse, causing the atria to contract. These one-way valves at the exits from each chamber ensure that blood flows in only 1 direction. As resistance to blood flow through the general circulation is much greater than resistance through the lungs, the left side of the heart must contract more forcibly than the right one that’s why it has greater muscular bulk.

Exercise 7. Answer the questions:

1. What does the cardiovascular system consist of?

2. What is the function of this system?

3. What does the word cardiovascular stand for?

4. Where is the heart located?

5. What does septum serve for?

6. What does each half of the heart consist of?

7. What are the valves of the heart?

8. What is the function of the right atrium?

9. What is the function of the left atrium?

10. What do one-way valves at the exits from each chamber ensure?

11. Why does the left side of the heart have greater muscular bulk?

Exercise 8. Match the two columns:

1. to pump 2. to contract 3. to oxygenate 4. to deoxygenate 5. to receive 6. to transfer 7. to enclose 8. to divide into 9. to supply 10. to compose of

a) to put together or make up by combining b) to separate into parts c) to acquire or get something d) to surround on all sides; close in e) to enrich with oxygen f) to raise or cause to flow by means of a pump g) to make available for use; provide h) to reduce in size by drawing together; shrink i)  to convey or remove something from one place to another j) to deprive of oxygen