- •Unit 1
- •Skeletal System
- •Bones
- •Long bones have long longitudinal axes and expanded ends. Examples are the arm and leg bones.
- •Short bones are somewhat cube like, with their lengths and widths roughly equal. The bones of the wrists and ankles are examples of this type.
- •Functions of Bones
- •Skeletal parts provide shape, support, and protection for body structures. They also act as levers that aid body movements, house tissues that produce blood cells and store various inorganic salts.
- •Joints of the Skeletal System
- •The Plan for Rendering the Text
- •Unit 3
- •1 Learn the key words and phrases:
- •2 Match the terms to following definitions:
- •the gap between the ends of the broken
- •bone
- •4) the remains of something broken
- •down or destroyed
- •5) a rigid dressing of gauze impregnated
- •with plaster of Paris for immobilizing a
- •diseased or broken part
- •Fractures
- •Repair of a Fracture
- •Meanwhile, phagocytic cells begin to remove the blood clot as well as any dead or damaged cells in the affected area. Osteoclasts also appear and resorb bone fragments, thus aiding in "cleaning up" debris.
- •Unit 5
- •Muscular System
- •Muscles, the organs of the muscular system, consist largely of cells that are specialized to undergo contractions. During these contractions, chemical energy from nutrients is converted into mechanical energy, or movement.
- •Atrophy and Hypertrophy of Skeletal Muscles
- •Pre-text assignments
- •Digestive System and Digestion
- •Unit 10
- •The Alimentary Canal
- •Unit 11
- •Stomach
- •Unit 12
- •Heart
- •Unit 19
- •Actions of the Heart
- •Unit 20
- •Blood Vessels
- •Unit 21
- •Paths of Circulation
4 Give the meaning of the following:
l) vasoconstriction |
a) inserting a catheter into the heart. |
2) cardiac murmur |
b) chest pain |
3) cardiac catheterization |
c) tightening of a vessel |
4) ischemia |
d) abnormal sound in the heart |
5) nitroglycerin |
e) twisted, dilated veins |
6) varicose veins |
f) abnormal heart rhythm |
7) infarction |
g) drug given for the relief of angina |
8) arrhythmia |
pectoris |
9) emboli |
h) area of dead tissue |
10) angina pectoris |
i) closure of a blood vessel |
11) occlusion |
j) insufficient blood flow to a tissue |
|
k) floating clots or other material carried |
|
in the bloodstream |
5 Tanslate the following:
1 The blood will have less oxygen combined with hemoglobin because the need of the active muscles has withdrawn more oxygen than in a restful state. 2 Cardiac failure may be present when the heart is functioning at 90 per cent efficiency or any fraction of the norma1 100 per cent effectiveness. 3 A drug extracted from a plant of the digitalis group is indicated in almost all cases of heart failure.
Actions of the Heart
Although the previous discussion described the actions of the heart chambers separately, they do not function independently. Instead, their actions are regulated so that the atrial walls contract while the ventricular walls are relaxed, and ventricular walls contract while the atrial walls are relaxed. Such a series of events constitutes a complete heartbeat or cardiac cycle. At the end of each cycle, the atria and the ventricles remain relaxed for a moment, and then a new cycle begins.
During a cardiac cycle, the pressure within the chambers of the heart rises and falls. For example, when the atria are relaxed, the blood flows into them from the large, attached veins. As these
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chambers fill, the pressure inside gradually increases. About 70% of the entering blood flows directly into the ventricles through the atrioventricular orifices before the atrial walls contract. Then, during atrial contraction (atrial systole), the atrial pressure rises suddenly, forcing the remaining 30% of the atrial contents into the ventricles.
Although the heart is a unit, anatomically and functionally, it can be thought of as two isolated pumps – the "right heart" and the "left heart". Normally the only route of communication between these two parts of the heart is the lung. The right heart receives blood from the veins and pumps it into the lung by way of the lesser circulatory system. In the lung the blood is supplied with oxygen. Then it moves into the left heart. From the left heart the well-oxygenated blood is pumped into a large artery called the aorta, which distributes it to the entire body by means of the greater circulatory system. The blood is returned to the heart by means of the veins. A continuous circulation is thus kept up.
Post-text assignments:
1 Respond to the following assignments:
1 Where is the heart located?
2 Name and locate the four chambers of the heart.
3 Name the structure that separates the right and left sides of the heart.
4 Describe the pressure changes that occur in the atria and ventricles during a cardiac cycle.
5 What causes heart sounds?
6 How do changes in body temperature affect the heart rate?
2 Add the proper combining form, suffix or prefix, to the parts of medical terms so as to fit their definitions:
1 A thickening and loss of elasticity in the inner walls of arteries, accompanied by the formation of the deposition of fatty compounds (athero...). 2 A thickening and loss of elasticity of the walls of the arteries, as in old age (...sclerosis). 3 Abnormal heart rhythms (...rrhythmia). 4 Inflammation of the endocardium (endocard...). 5 A narrowing or constriction of a passage, duct, opening (as in a mitral
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valve of a heart (mitral .. osis). 6 High blood pressure affecting the heart and blood vessels (...tension). 7 Inflammation of a vein (...itis). 8 Lack of oxygen in blood (de...genation). 9 The branch of medicine dealing with the heart, its functions, and its diseases (cardio...).
(a – a...; b - ...sclerosis; c – arterio...; d – sten...; e – ...itis; f – phleb...;g – hyper...; h – ...logia; i – oxy...)
3 Translate in writing:
The valves of the heart consist of leaflets of connective tissue, the surfaces being invested with a thin endothelial layer continuous with that of the heart chambers and great vessels. The connective tissue of each leaflet forms a tough fibrous sheet, the lamina fibrosa. The valve connective tissue also contains a significant amount of elastin. At the attached margins of each valve, the collagenous tissue becomes condensed to form a fibrous ring and the rings of 'the four valves together form a central fibrous "skeleton" which is continuous with the connective tissue of the myocardium, endocardium and epicardium.
4 Do you know that:
normocardia – a heart rate 60-100 beats/min tachycardia – a heart rate that exceeds 100 beats/min bradycardia – a heart rate of less than 60 beats/min
5 Give extended answers:
1 What do the contractions of the heart produce? 2 What is the cardiac cycle composed of? 3 What is the role of the ventricles and atria? 4 Describe the pulmonary circulation. 5 Describe the systemic circulations. 6 What are the corpuscular elements of blood? 7 What are the heart sounds? 8 Where is the first (second, third) heart sound heard? 9 What do heart sounds help the doctors to determine?
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