Анатомическая терминология в английском языке. Учебное пособие
.pdfWhile passing through the lung capillaries, blood absorbs the oxygen which entered the body during inhalation. The newly oxygenated blood next immediately returns to the heart through the pulmonary vein. The pulmonary vein is the only vein in the body which carries oxygen-rich blood. The circulation of blood through the vessels from the heart to the lungs and then back to the heart again is known as the pulmonary circulation.
Oxygen-rich blood enters the left side of the heart from the pulmonary veins/ The muscles in the left side of the heart pump the blood out of the heart through the largest single artery in the body, the aorta. The aorta moves up at first but then arches over dorsally and runs downward just in front of the vertebral column. The aorta divides into numerous branches which carry the oxygenated blood to all parts of the body. The names of some of these arterial branches: brachiocephalic, intercostal, esophageal, celiac, renal, and iliac arteries.
The relatively large arterial vessels branch further to form smaller arterioles. The arterioles, still containing oxygenated blood, branch into smaller tissue capillaries, which are near the body cells. Oxygen leaves the blood as it passes through the thin capillary walls to enter the body cells. There, involved in complicated chemical process, it combines with food to release needed energy.
One waste product of these chemical processes is carbon dioxide. It is produced in the cell but is harmful to the cell if it remains. It must thus pass out of the cells and into the bloodstream, at the same time that oxygen is entering the cell. As the blood makes its way back from the tissue capillaries toward the heart in venules and veins, it is full of carbon dioxide and deoxygenated.
The circuit is thus completed when deoxygenated blood enters the heart from the venae cavae. This circulation of blood from the body organs [except the lungs] to the heart and back again is called the systemic circulation. [2, c. 142–144]
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Task
Compare the following Latin terms with the corresponding English ones:
Oxygenium; arteria pulmonalis; vena pulmonalis; aorta ascendens; aorta descendens; arteria brachiocephalica; arteria intercostalis; arteria oesophagea; arteria coeliaca; arteria renalis; arteria iliaca; Carbonei dioxydum; circulus; organa corporis; pulmones
Developing Questions: Something to Think about
1.How is blood deficient in oxygen called?
2.Where does the blood become deoxygenated?
3.What is the pulmonary artery unusual in?
4.What is the pulmonary vein unusual in?
5.What section of the aorta is called ascending aorta?
6.What section of the aorta is called descending aorta?
Text 3. Anatomy of the Heart
The human heart weights less that a pound, it roughly the size of the human fist, and lies in the thoracic cavity, just behind the breastbone and between the lungs.
The heart is a pump, consisting of four chambers: two upper chambers called atria, and two lower chambers called ventricles.
NB! sing. atrium — plur. atria [from Latin]
It is actually a double pump, bound into one organ and synchronized very carefully. All the blood passes through each pump in a definite pattern. Pump station number one, on the right side of the heart, sends deoxygenated blood to the lungs, where the blood picks up oxygen and releases its carbon dioxide. The newly oxygenated blood returns to the left side of the heart to pump station number two and does not mix with the
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deoxygenated blood in pump station number one. Pump station number two then forces the oxygenated blood out to all parts of the body. At the body tissues, the blood loses its oxygen and upon returning to the heart, to pump station number one, deoxygenated blood is sent out to the lungs to begin the cycle anew.
Deoxygenated blood enters the heart through the two largest veins in the body, the venae cavae. The superior vena cava drains blood from the upper portion of the body, while the inferior vena cava carries blood from the lower part of the body.
The venae cavae bring deoxygenated blood which has passed through all of the body to the right atrium, the thin-walled upper right chamber of the heart. The right atrium contracts to force blood through the tricuspid valve into the right ventricle, which is the lower right chamber of the heart. The cusps of the tricuspid valve form a one-way passageway designed to keep the blood flowing only in one direction. As the right ventricle contracts to pump deoxygenated blood to the lung through the pulmonary artery, the tricuspid valve stays shut, thus preventing blood from pushing back into the right atrium.
The deoxygenated blood which enters the lung capillaries from the pulmonary artery soon loses its large quantity of carbon dioxide into the lung tissue and the carbon dioxide is expelled. At the same time, oxygen enters the capillaries of the lungs and is brought back to the heart within the pulmonary vein. The newly oxygenated blood enters the left atrium of the heart from the pulmonary vein. The walls of the left atrium contract to force blood through the mitral valve into the left ventricle.
The left ventricle has the thickest walls of all four heart chambers. It must pump blood with great force so that the blood travels through arteries to all parts of the body. The blood is pumped out of the left ventricle through the aortic valve and into the aorta, which branches to carry blood all over the body.
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The four chambers of the heart are separated by partitions called septa.
NB! sing. septum — plur. septa [from Latin]
The heart wall is composed of three layers. The endocardium is a smooth layer of cells which lines the inferior of the heart, and also is the material of which the valves of the heart are formed. The myocardium is the middle, muscular layer of the heart wall and is the thickest layer. The epicardium is a thin layer and forms the outermost layer of the heart wall. The pericardium is a delicate, double-folded membrane which surrounds the heart like a sac. [2, c. 144–146]
Task
Compare the following Latin terms with the corresponding English ones:
cor; atria cordis dextrum et sinistrum; ventriculi dexter et sinister; vena cava superior; vena cava inferior; valvula tricuspidalis; cuspis; arteria pulmonalis; vena pulmonalis; valvula mitralis; valvula aortalis; septum interatriale; septum interventriculare
Developing Questions: Something to Think about
1.The return of what blood to the left ventricle does the aortic valve prevent?
2.What does the interatrial septum separate?
3.What does the interventricular septum separate?
4.What heart layer is attached to the breastbone in front and to the diaphragm below?
5.Find and explain the term elements [combining forms] in the following terms: endocardium, myocardium, epicardium, pericardium?
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Text 4. Heartbeat
There are two phases of the heartbeat. These phases are called diastole [relaxation] and systole [contraction]. During diastole, the atria of the heart fill with blood from the venae cavae and the pulmonary vein. At the end of diastole, the atria contract and force blood into the ventricles through the tricuspid and mitral valves.
Systole begins as diastole ends. The ventricles, now filled with blood, contract and pump blood out of the heart. The right ventricle pumps blood to the pulmonary artery and lungs, and the left ventricle pumps blood into the aorta and its branches. The mitral and tricuspid valves close during systole to prevent the flow of blood back into the atria.
Systole, then, is the active contraction phase of the heartbeat, when the ventricles pump blood out of the heart. Diastole is the relaxation phase of the heartbeat, when the atria and ventricles fill with blood. [2, c. 146– 147]
Developing Questions: Something to Think about
1.What is the origin and meaning of the prefix in the term diastole?
2.What is the origin and meaning of the prefix in the term systole?
Text 5. Conducting System of the Heart
Primary responsibility for initiating the heartbeat rests with a small region of specialized muscle tissue in the posterior portion of the right atrium, where an electrical impulse originates. This region of the right atrium is called the sinoatrial node [S-A node]. The S-A node is also called the pacemaker of the heart. The current of electricity generated by the pacemaker causes the walls of the atria to contract and force blood into the ventricles, ending diastole.
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The wave of electricity passes from the pacemaker to another region of the myocardium. This region is at the posterior portion of the interatrial septum and is called the atrioventricular node [A-V node]. The A-V node immediately sends the excitation wave along to a region deep in the ventricle wall, called the bundle of His. From there the electrical wave passes to all parts of the ventricles and stimulates them to contract, pumping blood from the heart. A short rest period follows, and then the pacemaker begins the wave of excitation across the heart again. [2, c. 147–148]
Task
Compare the following Latin terms with the corresponding English ones:
nodus sinoatrialis; nodus atrioventricularis
Developing Questions: Something to Think about
1.How is the record used to detect the electrical changes in heart muscle called?
2.How many waves does the normal ECG show?
3.What nervous system regulates the heartbeat?
Review
Match the term for the cardiovascular system in 1 with an appropriate meaning in 2:
1)arteriole; capillary; atrium; aorta; venule; mitral valve; vena cava; tricuspid valve; pulmonary artery; pulmonary vein;
2)small vein; only artery which carries deoxygenated blood; largest vein in the body; lies between the left atrium and left ventricle; upper chamber of the heart; smallest of the blood vessels; only vein which carries oxygenated blood; small artery; lies between the right atrium and right ventricle; largest artery in the body.
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CHAPTER 6. RESPIRATORY SYSTEM
Text 1. Introduction
Respiration is referred to as the mechanical process of breathing, that is, the repetitive and, for the most part, unconscious exchange of air between the lungs and the external environment. This exchange of air at the lungs is also called external respiration. In external respiration, oxygen is inhaled into the air spaces [sacs] of the lungs and immediately passes into tiny capillary blood vessels surrounding the air spaces. Simultaneously, carbon dioxide, a waste product of the chemical combination of oxygen and food in cells, passes from the capillary blood vessels into the air spaces of the lungs to be exhaled.
While external respiration occurs between the outside environment and the capillary bloodstream of the lungs, another form of respiration is occurring simultaneously between the individual body cells and the tiny capillary blood vessels which surround them. This process is called internal [cellular] respiration. Internal respiration is the exchange of gases not at the lungs but at the cells within all the organs of the body. In this process, oxygen carried in the blood from the capillaries of the lung to the capillaries surrounding body cells passes out of the bloodstream and into the cells. At the same time, carbon dioxide, the waste produced in cells as oxygen chemically combines with food, passes from the tissue cells into the bloodstream and is carried by the blood back to the lungs to be exhaled. [2, c. 157–158]
Task
Compare the following Latin terms with the corresponding English ones:
respiratio externa; respiratio interna; sacculus; Oxygenium; Carbonei dioxydum
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Developing Questions: Something to Think about
1.How much oxygen does air inhaled contain? [clue: 21 per cent]
2.How much carbon dioxide does exhaled air contain? [clue: 16 per
cent]
Text 2. Anatomy and Physiology of Respiration
Air enters the body through the nose and passes through the nasal cavities which are lined with a mucous membrane and fine hairs [cilia] to help filter out foreign bodies, as well as to warm and moisten the air. Paranasal sinuses are hollow, air-containing cavities within the cranium. They, too, have a mucous membrane lining and function to provide the lubricating fluid mucus, as well as to lighten the bones of the skull and help produce sound.
After passing through the nasal cavities, the air next reaches the pharynx [throat]. There are three divisions of the pharynx. The nasopharynx is the first division, and is nearest to the nasal cavities. It contains the adenoids, which are masses of lymphatic tissue. Below the nasopharynx and closer to the mouth is the second division of the pharynx, the oropharynx. The tonsils, two rounded masses of lymphatic tissue, are located in the oropharynx. The third division of the pharynx is the hypopharynx [also called the laryngopharynx]. It is in the hypopharyngeal region that the pharynx, serving as a common passageway for food from the mouth and air from the nose, divides into two branches, the larynx [voice box], and the esophagus. The larynx contains the vocal cords and is surrounded by pieces of cartilage for support.
What prevents the passing of food or drink into the larynx and respiratory system after it has been swallowed? A special deterrent is provided for by a flap of cartilage attached to the root of the tongue which acts like a lid over the larynx. This flap of cartilage is called the epiglottis. The epiglottis lies over the mouth of the larynx [also called the glottis]. In the act of swallowing, when food and water move through the throat, the
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glottis automatically moves under the epiglottis, closing off the larynx so that food cannot enter.
On its way to the lungs, air passes from the larynx to the trachea [windpipe]. A vertical tube about 4,5 inches long and an inch in diameter. The trachea is kept open by rings of cartilage separated by fibrous connective tissue.
In the region of the mediastinum, the trachea divides into two branches called bronchi.
NB! sing. bronchus — plur. bronchi [from Latin]
Each bronchus leads to a separate lung, and divides and subdivides into smaller and finer tubes. The smallest of the bronchial branches are bronchioles. At the end of the bronchioles are clusters of air sacs called alveoli.
NB! sing. alveolus — plur. alveoli [from Latin]
Each alveolus is made of a one-cell layer of epithelium. The very thin wall allows for the exchange of gases between the alveolus and the capillaries which surround and come in close contact with it. The blood which flows through the capillaries accepts the oxygen from the alveolus and deposits carbon dioxide into the alveolus to be exhaled. Oxygen is combined with a protein [hemoglobin] in erythrocytes and carried to all parts of the body.
Each lung is enveloped in a double-folded membrane called the pleura. The outer layer of the pleura, nearest the ribs, is the parietal pleura, and the inner layer, closest to the lung, is the visceral pleura. The pleura is moistened with a serous secretion which facilitates the movements of the lungs within the chest.
The right lung is slightly larger of the two and divided into three lobes, and the left lung is divided into two lobes.
The lungs extend from the collarbone to the diaphragm in the thoracic cavity. The diaphragm is a muscular partition which separates the
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thoracic cavity from the abdominal one, and aids in the process of breathing. The diaphragm contracts and descends with each inspiration [breathing in]. The downward movement of the diaphragm enlarges the area in the thoracic cavity and reduces the internal air pressure so that air flows into the lungs to equalize the pressure. When the lungs are full, the diaphragm relaxes and elevates, making the area in the thoracic cavity smaller, and thus increasing the air pressure in the thorax. Air then is expelled out of the lungs to equalize the pressure; this is called expiration [breathing out]. [2, c. 159–162]
Task
Compare the following Latin terms with the corresponding English ones:
nasus; cavitates nasales; sinuses paranasales; pharynx; tonsilla; larynx; cartilago; epiglottis; trachea; bronchus; pulmo; alveolus; pleura parietalis / visceralis; lobus; diaphragma; inspiratio; expiratio
Developing Questions: Something to Think about
1.In whom are the adenoids more prominent, in children or in adults? Can the adenoids obstruct air passages, and in what case?
2.How are sounds produced? [clues: air; to expel; vocal cords; to
vibrate]
3.What determines the high or low pitch of the voice? [clue: tension of the vocal cords]
4.Explain the meaning of the prefix epiin the term epiglottis. What is the origin of this prefix, Greek or Latin?
5.Explain the meaning of the term erythrocyte by its term elements [combining forms]. What is the origin of this term, Greek or Latin?
6.Are the two lungs quite mirror images of each other?
7.Can the lung continue to function normally if one lobe is removed without damage to the rest of the lung?
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