医学英语新教程-习题参考答案Unit 4

UnitFourHumanPhysiologySectionA1—c2—g3—h4—b5—i6—a7—f8—e9—j10—dSectionBPassage1I.ReadingComprehension1.Whatdoesphysiologydealwith?Physiologyisthestudyofprocessesandfunctionsinlivingorganisms.Itisabroadfieldthatencompassesmanydisciplinesandhasstrongrootsinphysics,chemistry,andmathematics.Thescopeofphysiologyrangesfromtheactivitiesorfunctionsofindividualmoleculesandcellstotheinteractionofourbodieswiththeexternalworld.Animportantpartofphysiologyisunderstandinghowdifferentpartsofthebodyarecontrolled,howtheyinteract,andhowtheyadapttochangingconditions.2.Whatarethecommoncharacteristicsofdifferentformsofcells?Thoughcellsdifferwidelyinformandfunction,theyallhavecertaincommoncharacteristics.First,theyareboundedbyalimitingmembrane,theplasmamembrane.Secondly,theyhavetheabilitytobreakdownlargemoleculestosmalleronestoliberateenergyfortheiractivities.Thirdly,atsomepointintheirlifehistory,theypossessanucleuswhichcontainsgeneticinformationintheformofdeoxyribonucleicacid.3.Couldyoudescribethefunctionsoftherightventricleandtheleftventricle?Contractionsoftherightventriclepropeldeoxygenatedbloodthroughthelungswhereitabsorbsoxygenfromtheair,whiletheleftventriclepumpsoxygenatedbloodreturningfromthelungstotherestofbodytosupplythetissues.4.Howdoyouunderstandtheconceptofbalanceinthehumanbody?Theconceptofbalanceisveryimportanttohumanbody.Itcanbeappliedtoanyofthebodyconstituentsincludingwaterandsalt.Intakemustmatchrequirementsandanyexcessmustbeexcretedtomaintainbalance.Ifbalancecan’tbemaintainedwell,sicknessevendeathmayhappen.5.Whataretwocoordinatingsystemsandhowdotheyperformtheirfunctions?Twocoordinatingsystemsarethenervoussystemandtheendocrinesystem.Thenervoussystemcoordinatesthemovementsofthelimbsandbody,stimulatesthemusclestocontract,andsensesmuscletensionandlimbposition.Theendocrinesystemhelpsadjustbloodflowandthesupplyofvariousmetabolicsubstratestotheworkingmuscles.Theendocrinesystemproduceshormoneswhichtravelinthebloodstreamtothecellsuponwhichtheyexertaregulatoryeffect.6—A7—A8—D9—B10—DII.VocabularyStudyPartA1—platelets2—physiological3—Extracellular4—nitrogen5—Indigestible6—urinary7—lymphatic8—glycogen9—deoxygenated10—oxidationPartB1—excrete2—Evolution3—stabilize4—locomotion5—notion6—dysfunction7—intricate8—endowed9—liberate10—exquisitelyIII.TranslationPartA1.Thesuccessofphysiologyinexplaininghoworganismsperformtheirdailytasksisbasedonthenotionthattheyareintricateandexquisitemachineswhoseoperationisgovernedbythelawsofphysicsandchemistry.生理学成功地解释了生物体如何进行日常活动，基于的观点是生物体好比是结构复杂而灵巧的机器，其运行机制受物理和化学规律的调控。2.Althoughitishelpfultostudyhoweachorganperformsitsfunctions,itisessentialtorecognizethattheactivityofthebodyasawholeisdependentontheintricateinteractionsbetweenthevariousorgansystems.虽然研究各器官如何行使功能很有益处，但我们必须认识到机体作为一个整体所做的活动依赖于各器官系统间错综复杂的相互作用。3.Ifthereisanexcessofpotassiumintheextracellularfluid,thecardiacmusclecellsbecometooexcitableandmaycontractatinappropriatetimesratherthaninacoordinatedmanner.如果细胞外液中钾离子过多，心肌细胞的兴奋性增强，可能出现不规律收缩。4.Anegativefeedbacklooprequiresasensorofsomekindthatrespondstothevariableinquestionbutnottootherphysiologicalvariables.负反馈环是在机体出现紊乱时，通过感受器对出现的各种问题做出反应，而不是对其他生理变化做出反应。5.Eachfunctionalstructurecontributesitssharetothemaintenanceofhomeostaticconditionsintheextracellularfluid,whichiscalledtheinternalenvironment.每个功能结构都在维持细胞外液稳态方面发挥其作用，这称之为内环境。PartB1.血小板和血浆蛋白通过阻止伤口继续流血并修复伤口，从而维持机体的稳态。(hemostasis)Plateletsandplasmaproteinscontrolhemostasis,aprocessthatstopsbloodlossafterinjuryandpromoteswoundhealing.2.钠钾泵将钠离子（Na+）主动转运至细胞外，钾离子（K+）转运到细胞内。每3个钠离子被转运出细胞，就有2个钾离子被转运到细胞内。(transport)Asodium-potassiumpumpactivelytransportssodiumions(Na+)totheoutsideandpotassiumions(K+)totheinside,withthreeNa+movedoutforeverytwoK+movedin.3.体内的水平衡由位于大脑下丘脑的渗透压感受器自动调控。(regulate)Waterisautonomicallyregulatedbyosmoreceptorslocatedinthehypothalamusofthebrain.4.营养物质和液体由小肠绒毛内的毛细血管吸收进入血液循环系统。(absorb)Capillarieswithinthevilliofthesmallintestinearesiteswherenutrientsandfluidsareabsorbedintothecirculatorysystem.5.所有的细胞每时每刻都需要氧气（O2），并不断排出二氧化碳（CO2）等代谢废物。(eliminate)Allcellsrequireacontinuoussupplyofoxygen(O2)andmustcontinuouslyeliminatemetabolicwasteproducts,suchascarbondioxide(CO2).Passage21—T2—F3—T4—T5—F6—F7—T8—T9—F10—T