医学专业英语Chapter5RespiratorySystem

1、精品文档Chapter 5Respiratory SystemIn this passage you will learn: The organs of the respiratory system The structure and function of these organs The mechanism of breathing The gas transport and cleaning systemAll living animals must take in oxygen and get rid of carbon dioxide. In the vertebratesanima

2、ls with backbones that get their oxygen from the air, both tasks are performed by special gas-exchange organs called lungs. The lungs provide a place where oxygen can reach the blood and carbon dioxide can be removed from it. They are equipped with tubes and a bellows system for drawing in air from

3、the outside, while the pulmonary veins and arteries circulate blood through from inside. The lungs also have a cleaning system that traps, ejects, or destroys irritants and other harmful substances that travel in with the air.In the simpler cold-blooded amphibians and reptiles, the lungs are two bal

4、loon-like sacs. In active animals that require large amounts of oxygen, especially the warm-blooded birds and mammals , the lungs are a spongy labyrinth of sacs that supply an enormous surface area for the transfer of gases. In the adult human the total lung surface, if flattened out, would be large

5、r than a badminton court, about 100 square yards (83 square meters).Air enters the body through the nose and passes through the nasal cavity, which is 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

6、hollow, air-containing spaces within the skull that communicate with the nasal cavity. 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 cavity, the air nex

7、t reaches the pharynx (throat). There are three divisions of the pharynx. The nasopharynx is the first division, and it is nearest to the nasal cavities. It contains the adenoids, which are masses of lymphatic tissue. The adenoids (also known as the phary ngeal ton sils) are more prominent in childr

8、e n, and if en larged, they can obstruct air passageways . Below the nasopharynx and closer to the mouth is the second division of the pharynx, the oropharynx. The palatine tonsils, two rounded massed of lymphatic tissue, are located in the oropharynx. The third division of the pharynx is the hypoph

9、arynx (also called the laryn gophary nx).It is in the hypophary ngeal regi on that the phary nx, serv ing as a com mon passageway for food from the mouth and air from the no se, divides into two bran ches, the lary nx (voice box) and the esophagus.The esophagus leads into the stomach and carries foo

10、d to be digested. The lary nx contains the vocal cords and is surrounded by pieces of cartilage for support. Sounds are produced as air is expelled past the vocal cords, and the cords vibrate. The tension of the vocal cords determ ines the high or low pitch of the voice.Since food entering from the

11、mouth and air entering from the nose mix in the pharynx, what prevents the passing of food or drink into the larynx and respiratory system after it has been swallowed? Even with a small quantity of solid or liquid matter finding its way into the air passages, breath ing could be seriously blocked. A

12、 special deterre nt to this event is provided for by a flap of cartilage attached to the root of the tongue that acts like a lid over the larynx. This flap of cartilage is called the epiglottis. The epiglottis lies over the entrance to the larynx. In the act of swallowing, when food and liquid move

13、through the throat, the epiglottis closes off the larynx, so that these things cannot en ter.On its way to the lun gs, air passes from the lary nx to the trachea (win dpipe), a vertical tube about 4 12 inches long and 1 inch in diameter. The trachea is kept open by 16-20 C-shaped rings of cartilage

14、separated by fibrous connective tissue that stiffens the front and sides of the tube. In the region of the mediastinum, the trachea divides into two branches called bronchi. Each bronchus leads to a separate lung and divides and subdivides into smaller and finer tubes, somewhat like the bran ches of

15、 a tree (see Figure 6-1).AlrrnliBrnfwhjolw,lapillanm曲urtBnine-hiPt fi uni ewicyDiaphragmFigure 6-1The smallest of the bronchial branches are called bronchioles. At the end of the bronchioles are clusters of air sacs called alveoli. Each alveolus is made of a on e-cell layer of epithelium. The very t

16、hin wall allows for the exchange of gases between the alveolus and the capillaries that surro und and come in close con tact with it. The blood that flows through the capillaries accepts the oxyge n from the alveolus and deposits carb on dioxide into the alveolus to be exhaled. Oxyge n is comb ined

17、with a hemoglob in 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 moist

18、ened with a serous secretion that facilitates the movements of the lungs within the thorax.The two lungs are not quite mirror images of each other. The right lung, which is the slightly larger of the two, is divided into three lobes, or divisio ns, and the left lung is divided in to two lobes. It is

19、 possible for one lobe of the lung to be removed without damage to the rest, which can continue to function normally; The uppermost part of the lung is called the apex, and the lower area is the base. The hilum of the lung is the midline region where blood vessels, nerves, and bron chial tubes en te

20、r and exit the orga n.The lungs exte nd from the collarb one to the diaphragm in the thoracic cavity. The diaphragm is a muscular partition that separates the thoracic from the abdominal cavity and aids in the process of breath ing. The diaphragm con tracts and desce nds with each in halati on (in s

21、pirati on) .The dow nward moveme nt of the diaphragm en larges 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

22、, and thus increasing the air pressure in the thorax. Air then is expelled out of the lungs to equalize the pressure; this is called exhalation (expiration) . Other parts are also involved in the process. The cycle of respiration really begins when the phrenic nerve stimulates the diaphragm to contr

23、act and flatten. Also, the intercostal muscles between the ribs aid in inspiration by pulling the ribs up and out. The measure of how easily the lungs expand under pressure is compliance.Breathing is regulated unconsciously by center in the brainstem. These centers adjust the rate and rhythm of brea

24、thing according to changes in the composition of the blood, especially the concentration of carbon dioxide.Gas Transport. Oxygen is carried in the blood bound to hemoglobin in red blood cells. The oxygen is released to the cells as needed. Carbon dioxide is carried in several ways, but is mostly con

25、verted to an acid called carbonic acid. The amount of carbon dioxide that is exhaled is important in regulating the acidity or alkalinity of the blood. If too much carbon dioxide is exhaled by hyperventilation, body fluids tend to become more alkaline, a condition termed alkalosis. If too little car

26、bon dioxide is exhaled as a result of hypoventilation, body fluids tend to become more acid, a condition termed acidosis.The cleaning system of the lungs has four main components. Lining the trachea and bronchial tree are cells that secrete mucus, which traps pollutants and bacteria. Also in the bro

27、nchi are cells containing tiny cilia, that project into the blanket of mucus and with constant wavelike motions push the mucus up out of the airways. Irritating chemicals, stagnant and excessive mucus, and large bits of foreign matter are forcibly ejected as sputum from the bronchi by a cough. This

28、third important cleaning device like breathing, under partial voluntary control is a rapid muscle contraction and bronchial-tube constriction that generates a wind force far stronger than a tornado. Small harmful substances that make their way into the alveoli are destroyed by the fourth line of def

29、ense, the macrophages. These are patrolling cells that swallow up foreign particles or destroy them with enzymes.New Words and Phrases vertebrate Vlibreit jii.脊椎动物 behwsi bclauz；!.凤箱 lEiani 迪刘仏 剌激物 amplnbw xmfibijtljn.两栖动物 repiile repiailln.靶行动物 ballwnlike boluTlIaik adj.像P球的 wambblooded . won*bLdid

30、,adj.热血的 mammill mannal Ih. 甫乳动物 hlyrinth 13ebtrir）9 n.迷宫 badmintion court I beEbniintVk.711”.削毛球场 paranasial jpseroneizalJadj.鼻侧的 $inu f sainasln.鹫PararmaJ sinuses ars hollow, air-conlaining spaces nithin the nkull ifuii cvmmunicaif with the nasal cavity.（这里communicaLr的意思是相通） lubric-ating lu：brikei

31、ttr|.adj.润帘的 naKipluuynx ineizjufaeriijksln.鼻咽 adenoids acdinDidzn.腺状肿大 pharyngeal l farindjiJadj. Og 的 lomib tjnsizJn.扁桃腺 passapt*wuy paesidjwei n.过道 oropharynx ,gfa?rirjks In. 口咽 palatine ; pSElatain adj.上腭的 mtosed marstailj.集聚的cpw 冲 Ll（yv2t 习 it 宙!崔pcpjoju pLprqju* 训至丄屈 旳创a尸琳吟卩即 萃 UKqrwpuriuf Wqr

32、aa （HiuoujJu 谓诜qqtUfcU qT u+ 廳傳擲 呻叫“卯兀戸q11宝卑 pXbobpmiufeq pnbwp uuq?n wj） 上咖開 |uufob|jgiiMjf 戸Lpdn&gcq师可 ir 嘲濮 pkbobjmAjx pnbrxi jKutljr? ir 上臨hItcoIus Edvhhs（l 复alveoli feelvilai） e 肺泡piihLiuni上皮；上皮细胞doublpfblii dAbifauldidlaiij.双/厳折卷的 pleura I pludro . n,胸噢 viM?eral visoraljadj.内脏的 mirmr image mir

33、imidg n+ 镜像 lube hub ii,肺叶 uppenoosL , Apomoust adj.最上的 spei ipeksln.尖端 hilum haihmn. D（肺门） midbne midlainjrt 一 中间线 caUaitonc kjilaboUii n.锁骨 diaphnkgm daiafraemn.横號膜 partition po; tijan |n.分隔*分配；隔壁隔膜 inhalaliw : jinha leifanln.吸入 iiispiratinn Liinspreifn .n,吸人 ihoraci* . tbAraesik ifldj * 蒯腔的 exhul

34、aiion t kCksho leifonln.呼出 expiration , tek$pijn, 呼出vbllion L ivcnlfleijanjn.空*（流通 phrenic fremik adj,橫膈膜的 （xjnipliani . kmiplakwisln. JWlit imAiooatal lintaJostladj 肋间的The menn* of how 出isily ihtt lunp rxpajid undtr 卩refiun1 is tnniplianrp.（这电的意思是輔器官 之所以庄压力下能轻松地张开是因为它能够噸勢而为，畝其自然）。bruinsUri I breins

35、iem n.脑干rhythm ridanH 霸律 acidity oditiln.酸度 alkalinity .EElkdlinitiln.碱I艮 hrvfntilatioii .haipSiventiIeiJnn.通汽过曼 alkaltwiH Llkbusiisn,诚中理hjpovnbhiion ihaigUi*歧HtikdJ颉 门”通.”、足， pollutant l po lu;tJAtn.芾染物质 wavl ikc | weivlaik |adj.波浪状的 iiriuting hriteitir）adj.剌截性的 dLigmirit L stanjnt .adj* 停滞的 sputum

36、 Cspjuamnr 痰 coriBiricthjTi I. knstrikfjnjn.收缩 tornado Eneidjulm 旋风i* 施卷风ExercisesA. Discuss the following topics:1. Imagine you were lecturing in front of rural health workers on the topic of respiratory system, draw a picture to illustrate the whole system.2. Describe their structures and function

37、s.3. How can epiglottis prevent the passing food and drink into the respiratory system?4. What role does the diaphragm play in the process of breath ing?5. What are the four comp onents of the clea ning system? How do they function?B. Fill in the bla nks with the words give n below and cha nge their

38、 forms if n ecessary.alveolusdiaphragmthoracic cavityparietal pleuramediasti numcapillaryhemoglob ingas excha ngevisceral pleurapleural spaceThe lungs are two cone-shaped, spongy organs consisting of alveoli, blood vessels, elastic tissue and n erves. Each of the two lungs con sists of smaller divis

39、i ons called lobes; the left lung hastwo lobes, while the right l ung is divided into three lobes. In the lun gs, ( 1 ) are surro un ded by a network of tiny blood vessels called capillaries; oxygen from the lungs passes into these ( 2 ) for distributio n to tissue cells, while carb on dioxide from

40、the blood passes into the lungs to be expelled by exhalati on. Once absorbed into blood cells, oxyge n becomes attached to ( 3 ) and is released to tissue cells as needed. Thus, the primary function of the lungs is to bring air into close con tact with blood, which allows ( 4 ) to occur.The lungs ar

41、e surroun ded by a membra ne called the ( 5 ). The space that the lungs occupywithin the chest is called the ( 6 ), which is lined by a membra ne called the ( 7 ). The parietaland visceral pleurae lie very close to each other; the small space between theses membranes, called the ( 8 ) , is filled wi

42、th a fluid that prevents friction when the two membranes slide against each other duri ng respirati on. In the cen tral portion of the thoracic cavity (in the area betwee n the lungs) is a space called the ( 9 ) , which contains the heart. A group of smooth muscles called the (10 ) separates the low

43、er portion of the thoracic cavity from the abdome n.C. Match Colu mn I with Colu mn n.Colu mn IColu mn IIbronchiole1 any of the small subdivision of the bronchicompliance2 the peak portion of the lungsa condition in which there is too much carbon dioxide in thehypoventilation3 bloodintercostal4 betw

44、een the ribsparanasal sinuses5 air-conditioning cavities in the bones near the nosea condition in which there is too much carbon dioxide in theacidosis6 bloodapex7weak , inadequate exchange of gasrounded masses of lymph tissue in the oropharynx ( palatinepharynx8 means roof of the mouth).alkalosis9

45、in agreement withthroat; composed of the nasopharynx, oropharynx, andpalatine tonsils10 laryngopharynx.D. Define the following terms of the respiratory system in line with the text you have just,learned (mak ing use of the vocabulary provided in the brackets if n ecessary), for example:Oxyge n (gas,

46、 cell, release en ergy fromfood, metabolism)1. mirror image (as see n, right side,as if, left side, vice versa)2. ade no ids (lymphatic tissue, n asophar- ynx)3. alveolus (air sac, gas excha nge, in respirati on)4. bron chus (ma in bran ch, trachea, mediasti num)5. epiglottis ( leaf-shaped, cartilag

47、e, larynx, preve nt, trachea)6. hyperve ntilati on(extreme, rapid,deep, result in, alkalosis)7. diaphragm (dome-shaped, muscle, move, in crease, decrease, space, thoracic cavity)8. phary nx ( com mon, passageway, esophagus, food, air, lary nx)9. pleura (double-layered, membra ne, visceral pleura, pa

48、riatal pleura, thoracic cavity)10. sputum ( substa nee,releases,cough ing, cleari ng the throat, respiratory tract)E. Tran slate the followi ng into En glish.I. 副鼻窦3.脊椎动物5.二氧化碳7横膈膜神经9.威慑物II. 滞痰13.纵隔15.碱中毒仃.污染物质19.上皮；上皮细胞 2口咽4.肺泡6.肺换气不足8.双重折叠的10.润滑液12.食管14.哺乳动物16谜宫18.脑干20.刺激物Passage Two Respiratory D

49、isorders and DiseasesIn this passage you will lear n: Various disorders and diseases of the respiratory system Their defi niti ons, causes and treatme nt Detailed description of the signs and symptoms of chronic obstructive pulmonary disease Medical terms pertaining to the diseases of the respirator

50、y system The respiratory system is subject to a wide variety of disorders and diseases. The most frequent attacks come from common cold and flu viruses. Other diseases that affect the lungs include bacterial infections such as pneumonia and tuberculosis. The lungs are especially vulnerable to allerg

51、ic dis- eases such as asthma. There are more serious diseases such as respiratory distress syndrome, emphysema, chronic obstructive pulmonary diseases (COPD), lung cancer, etc.Influenza and pneumonia. Influenza is a viral disease of the respiratory tract. Different strains of the influenza virus hav

52、e caused serious epidemics through history. Pneumonia is caused by several different microorganisms. The name represents any inflammation of the lungs caused by infection, so an alternate term for pneumonia is pneumonitis. Streptococcal pneumonia usually involves one or more lobes of the lung and de

53、scribed as lobar pneumonia. Other agents of pneumonia localize in the bronchial tubes, causing bronchopneumonia.Pleurisy is severe chest pain accompanying each deep breath in a person with an inflamed pleura, the twin membranes around each lung and lining the chest cavity. Pleurisy can attend pneumo

54、nia or result from direct infection of the pleura.Tuberculosis (TB )has increased in recent years along with the rise of AIDS and the appearance of resistance to antibiotics in the organism that causes the disease. The name of the disease comes from the small lesions, or tubercles, that appear with

55、the infection. The symptoms of TB include fever, weight loss, weakness, cough, and as a result of damage to blood vessels in the lungs, hemoptysis, i. e. the coughing up of phlegm (sputum) containing blood. Accumulation of exudate in the alveoli may result in solidification or consolidation of lung

56、tissue. The tuberculin test is used to reveal tuberculosis infection, PPD (purified protein derivative) is the form of tuberculin commonly used.Asthma . Attacks of asthma result from narrowing of the bronchial tubes. The constriction, along with edema, swelling of the bronchial linings, and accumula

57、tion of mucus results in wheezing, extreme dyspnea and cyanosis. Although the cause of asthma is uncertain, foreign particles such as pollen or certain environmental pollutants are believed to be the culprits, which stimulate the smooth muscle of the bronchial tree to releases histamine causing the

58、muscle to contract. The bronchial airways are consequently restricted. Treatment of asthma includes removal of allergens, administration of bronchodilators to widen the airways, and administration of steroids.Respiratory distress syndrome is a disorder of some prematurely bom infants. The alveoli of afflicted babies are lined with a protein material, limiting the amount