The Anatomy of the Heart

The heart is a muscle, about the size of your fist that is encased in a sac called the pericardium. The pericardium helps to keep the heart in position and protects it from getting hurt. The pericardium and the heart are separated by a layer of lubricating fluid which allows the heart to pump freely inside the walls of the chest. The heart is made up of three layers of muscle, the endocardium, myocardium and epicardium. The myocardium makes up about seventy five percent of the heart tissue. The epicardium is a thin lining that covers the myocardium. There is a layer called the endocardium that is between the myocardium and the inside of the heart. The endocardium acts as the inner covering of the heart and protects the myocardium.

The heart functions as a pump that circulates nourishment and oxygen to, and carbon dioxide and waste away from, tissues and organs of the body. The heart is separated into four different chambers through which blood is pumped. The heart is separated by a thick wall of muscle called the septum, which divides the heart into two halves. Each half is then separated into an upper and lower chamber by valves. The upper chambers are called the atria and are the inputs to the heart. The lower chambers are called the ventricles and are the outputs of the heart.

The valves that separate the upper and lower chambers are called the atrioventriclular valves. The valve that separates the right atrium from the right ventricle is called the tricuspid valve and the valve that separates the left atrium from the left ventricle is called the mitral valve. A different set of valves controls the flow of blood from each ventricle to the main arteries. The valve that separates the right ventricle from the pulmonary artery, the artery that carries blood to the lungs, is called the pulmonary valve. The aortic valve is the valve that separates the left ventricle from the aorta, the main artery that carries blood to the rest of the body's organs and tissues.

Exercise 16.Give Ukrainian equivalents to the following medical terms and word combinations.

main artery, aortic valve, pulmonary valve, right ventricle, mitral valve, pulmonary artery, different set of valves, tricuspid valve, atrioventricular valves, upper chamber, lower chamber, septum, epicardium, myocardium, endocardium, pericardium, thick wall of muscle, inputs to the hear, outputs of the heart, protects the myocardium, thin lining, a layer of lubricating fluid, inner covering of the heart, circulates nourishment.

Exercise 17. Answer the following questions:

1. What is the size of the heart?

2. What does the pericardium help to?

3. What are the pericardium and the heart separated by?

4. What is the heart made up?

5. What is the function of the heart?

6. How many chambers is the heart separated into?

7. What are functions of different valves?

8. What valves is the heart separated by?

9. What is the function of the main artery?

Exercise 18. Form nouns form the following verbs.

To separate, to nourish, to divide, to control, to carry, to depolarize, to move, to pass, to change, to differ, to concentrate, to stimulate, to act, to relax, to contract, to pump, to indicate, to detect, to create, to conduct.

Exercise 19. Change the following sentences into the Passive.

1. The septum divides the heart into two halves.

2. The mitral valve separates the left atrium from the left ventricle.

3. The heart pumps nourishment and oxygen to tissues and organs of the body.

4. The aortic valve separates the left ventricle from the aorta.

5. A different set of valves controls the flow of blood from each ventricle to the main arteries.

6. Three layers of muscle make up the heart.

7. A layer of lubricating fluid separates the pericardium and the heart.

8. The pericardium protects the heart.

9. The pulmonary valve separates the right ventricle from the pulmonary artery.

10. The endocardium protects the myocardium.

11. The epicardium covers the myocardium.

12. The tricuspid valve separates the right atrium from the right ventricle.

Exercise 20. Retell the text “The anatomy of the heart”.

Exercise 21. Read and translate the text in a written form.