heart – сердце muscular – мышечный cardiac – сердечный to pump – качать endocardium – эндокардиум innermost – самый внутренний conducting system – проведение системы subendocardial – внутрисердечный impulse – импульс fibrosi – фиброзные кольца
Intrapulmonary bronchi: the primary bronchi give rise to three main branches in the right lung and two branches in the left lung, each of which supply a pulmonary lobe. These lobar bronchi divide repeatedly to give rise to bronchioles. Mucosa consists of the typical respiratory epithelium. Submucosa consists of elastic tissue with fewer mixed glands than seen in the trachea. Anastomosing cartilage plates replace the C-shaped rings found in the trachea and extra pulmonary portions of the pri тагу bronchi. Bronchioles do not possess cartilage, glands, or lymphatic nodules; however, they contain the highest proportion of smooth r muscle in the bronchial tree. Bronchioles branch up to 12 times to supply lobules in the lung. Bronchioles are lined by ciliated, simple, columnar epithelium with nonciliated bronchiolar cells. The musculature of the bronchi and bronchioles con tracts following stimulation by parasympathetic fibers (vagus nerve) and relaxes in response to sympathetic fibers. Terminal bronchioles consist of low-ciliated epithelium with bronchiolar cells. The costal surface is a large convex area related to the inner surface of the ribs. The mediastinal surface is a concave medial surface, contains the root, or hilus, of the lung. The diaphragmatic surface (base) is related to the convex sur face of the diaphragm. The apex (cupola) protrudes into the root of the neck. The hilus is the point of attachment for the root of the lung. It contains the bronchi, pulmonary and bronchial vessels, lym phatics, and nerves. Lobes and fissures. The right lung has three lobes: superior, middle and inferior. The left lung has upper and lower lobes. Bronchopulmonary segments of the lung are supplied by the segmental (tertiary) bronchus, artery, and vein. There are 10 on the right and 8 on the left. Arterial supply: Right and left pulmonary arteries arise from the pulmonary trunk. The pulmonary arteries deliver deoxygenated blood to the lungs from the right side of the heart. Bronchial arteries supply the bronchi and nonrespiratory por tions of the lung. They are usually branches of the thoracic aorta. Venous drainage. There are four pulmonary veins: superior right and left and inferior right and left. Pulmonary veins carry oxygenated blood to the left atrium of the heart. The bronchial veins drain to the azygos system. Bronchomediastinal lymph trunks drain to the right lymphatic duct and the thoracic duct. Innervation of Lungs: Anterior and posterior pulmonary plexuses are formed by vagal (parasympathetic) and sympathetic fibers. Parasympathetic stimulation has a bronchoconstrictive effect. Sympathetic stimulation has a bronchodilator effect.
lungs – легкие intrapulmonary bronchi – внутрилегочные бронхи the primary bronchi – первичные бронхи lobar bronchi – долевые бронхи submucosa – подслизистая оболочка
28. Respiratory system
The respiratory system is structurally and functionally adapt ed for the efficient transfer of gases between the ambient air and the bloodstream as well as between the bloodstream and the tissues. The major functional components of the res piratory system are: the airways, alveoli, and bloodvessels of the lungs; the tissues of the chest wall and diaphragm; the systemic blood vessels; red blood cells and plasma; and respi ratory control neurons in the brainstem and their sensory and motor connections. LUNG FUNCTION: provision of 02 for tissue metabolism occurs via four mechanisms. Ventilation – the transport of air from the environment to the gas exchange surface in the alveoli. 02 diffusion from the alveolar air space across the alveolar-capillary membranes to the blood. Transport of 02 by the blood to the tissues: 02 diffusion from the blood to the tissues. Removal of C02 produced by tissue metabolism occurs via four mechanisms. C02 diffusion from the tissues to the blood. Transport by the blood to the pulmonary capillary-alveolar membrane. C02 diffusion across the capillary-alveolar membrane to the air spaces of the alveoli. Ventilation – the transport of alveolar gas to the air. Functional components: Conducting airways (conducting zone; anatomical dead space). These airways are concerned only with the transport of gas, not with gas exchange with the blood. They are thick-walled, branching, cylindrical structures with ciliated epithelial cells, goblet cells, smooth muscle cells. Clara cells, mucous glands, and (sometimes) cartilage. Alveoli and alveolar septa (respiratory zone; lung parenchyma). These are the sites of gas exchange. Cell types include: Type I and II epithelial cells, alveolar macrophages. The blood-gas barrier (pulmonary capillary-alveolar membrane) is ideal for gas exchange because it is very thin (‹ 0,5 mm) and has a very large surface area (50 – 100 m 2 ). It consists of alveolar epithelium, basement membrane interstitium, and capillary endothelium.