最新The Digestive System - McGraw- Hill Education：消化系统-麦格劳-希尔教育-药学医学精品资料.ppt

《最新The Digestive System - McGraw- Hill Education：消化系统-麦格劳-希尔教育-药学医学精品资料.ppt》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、最新TheDigestiveSystem-McGraw-HillEducation：消化系统-麦格劳-希尔教育-药学医学精品资料LearningOutcomes29.1Listthefunctionsofthedigestivesystem.29.2Tracethepathwayoffoodthroughthealimentarycanal.29.3Describethestructureandfunctionsofthemouth,teeth,tongue,andsalivaryglands.29.4Describethestru

2、ctureandfunctionofthepharynx.2LearningOutcomes(cont.)29.5Describetheswallowingprocess.29.6Describethestructureoftheesophagusandtellhowitpropelsfoodintothestomach.29.7Describethestructureandfunctionsofthestomach.29.8Listthesubstancessecretedbythestomachandgivetheirfunct

3、ions.3AlimentaryCanalWallofalimentarycanalMucosaInnermostlayer;epithelialtissueSecretesenzymesandmucusintolumenAbsorbsnutrientsSubmucosaInferiortomucosa;looseconnectivetissue,bloodvessels,glands,andnervesBloodvesselscarryawayabsorbednutrientsMuscularlayerJustoutsidesub

4、mucosa;layersofsmoothmuscleContractstomovematerialsthroughthecanal7AlimentaryCanal(cont.)SerosaDouble-walledoutermostlayer:peritoneumVisceralperitoneumInnermostwallofserosaSecretesserousfluidtokeepoutsideofcanalmoistParietalperitoneumAbdominalliningMovementsChurning–mi

5、xessubstancesinthecanalPeristalsis–propelssubstancesthroughthetract8ApplyYourKnowledgeWhatarethelayersofthewallofthealimentarycanalandwhatdotheydo?ANSWER:Thelayersare:Mucosa:innermostlayer;secretesenzymesandmucusintothecanalandabsorbsnutrientsSubmucosa:inferiortothemuc

6、osa;carriesawayabsorbednutrientsMuscularlayer:justoutsidethesubmucosa;contractstomovematerialsthroughthecanalSerosa:double-walledouterlayer;secretesserousfluidtokeepoutsideofcanalmoistBravo!9TheMouthBuccalcavityMechanicaldigestionTakesinfoodandreducesitssizebychewingSt

7、artschemicaldigestionSalivacontainstheenzymeamylase,whichbreaksdowncarbohydrates10TheMouth(cont.)CheeksholdfoodinmouthLips–sensorynervefibersthatjudgetemperatureoffoodTongueSkeletalmusclescoveredbymucousmembraneLingualfrenulum–holdstonguetofloorofmouthMixesfood,holdsfo

8、odbetweenteeth,containstastebudsLingualtonsils–lymphatictissuedestroysbacteriaandvirusesonbackoftongue11TheMouth(cont