Respiratory systemHongyaSunYangzhou University
Respiratory system Hongya Sun Yangzhou University 1
OBJECTIVESThis chapter should help you to:Know the structure and function of olfactory epitheliumMasterthestructuralfeaturesoftracheaandtheirrelationtofunction.Masterthekeydistinguishingfeaturesof thevarioussegments ofpulmonary conductingportionMasterthe composition and structureof pulmonaryrespiratoryportion.MasterthestructureandfunctionofalveolusMasterthecomponentsofblood-airandthefunctionoflungmacrophages
2 OBJECTIVES This chapter should help you to: l Know the structure and function of olfactory epithelium l Master the structural features of trachea and their relation to function. l Master the key distinguishing features of the various segments of pulmonary conducting portion. l Master the composition and structure of pulmonary respiratory portion. l Master the structure and function of alveolus. l Master the components of blood-air and the function of lung macrophages
I.General descriptionA.Components-nasalcavity,pharynx,larynx--tracheaCounducting--primary bronchiportionbronchi of various sizesbronchiolesterminalbronchioles--lungrespiratorybronchiolesRespiratoryalveolarductsalveolarsacsportionalveoli
Ⅰ.General description A. Components -nasal cavity, pharynx, larynx -trachea -primary bronchi -lung respiratory bronchioles alveolar ducts alveolar sacs alveoli bronchi of various sizes Counducting portion Respiratory portion bronchioles terminal bronchioles 3
TracheaPrimarybronchusOlfactorySecondarybronchiepitheliumNasal cavityNasopharynxOropharynxRight lungLeft lungConductingportionLarynxBronchiole(1mmorlessin.diameter)TracheaTerminalbronchioleBronchiolesRespiratorybronchioleRespiratory-BronchtbronchiolesLungZAlveolarduct心RespiratoryAlveolarductsportionTerminal.-alveoliAlveolarsacDiaphragm(terminationofalveolarduct)
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B. function1.Counductingportion-toprovide a conduitthrough whichair cantraveltoand fromthe lungs and conditiontheinspired air--to ensure an uninterrupted supply of air--to clean,moisten,and warm the inspired air--others: voice, olfaction , etc2.Respiratoryportion-exchageofgasestakesplace
B. function 1.Counducting portion -to provide a conduit through which air can travel to and from the lungs and condition the inspired air -to ensure an uninterrupted supply of air -to clean,moisten,and warm the inspired air -others: voice, olfaction , etc. 2.Respiratory portion -exchage of gases takes place 5
Olfactorymucosa--Location:are located in the superior conchaewhich located in the roof of the nasal cavity--in humans ,it about 10cm? in area and up to100mm in thickness--it is lined by olfactory epithelium which servesas a chemoreceptor for the sense of smell6
Olfactory mucosa -Location:are located in the superior conchae which located in the roof of the nasal cavity -in humans ,it about 10cm² in area and up to 100mm in thickness -it is lined by olfactory epithelium which serves as a chemoreceptor for the sense of smell 6
OlfactorymucosaA.olfactory epitheliumSupportingcell一--it is a pseudostratifiedcolumnarepitheliumOlfactorycell一--composed of 3 cell types:supportingcellsBasalcell②basalcellsolfactorycellsBowman'sglandAxons
Olfactory mucosa A. olfactory epithelium -it is a pseudostratified columnar epithelium -composed of 3 cell types: ①supporting cells ②basal cells ③olfactory cells 7
Olfactorycilia①supportingcellsOlfactoryvesicle--have broad,cylindrical apexesandnarrowerbases-ontheirfree surface are-Supportingmicrovillicell--well-developedjunctionalOlfactorycomplexescell-cantain a light yellow pigment-Axonthat is responsible for the coloroftheolfactorymucosaShwanncell8
① supporting cells -have broad ,cylindrical apexes and narrower bases -on their free surface are microvilli -well-developed junctional complexes -cantain a light yellow pigment that is responsible for the color of the olfactory mucosa Olfactory vesicle Olfactory cilia Supporting cell Olfactory cell Axon Shwann cell 8
basal cellsSupportingcell-- are smallercellsOlfactory2--They are spherical or cone-cell日shaped and form a singlelayer at the base of theBasalcellepithelium--They are relativelyundifferentiatedcellsBowman's gland-Axons
② basal cells - are smaller cells -They are spherical or cone- shaped and form a single layer at the base of the epithelium -They are relatively undifferentiated cells 9
Olfactory③olfactorycellscilia--Theyare bipolarneuronsOlfactory-Their nuclei liebelowthenuclei ofvesiclesupportingcells--The apical dendrites are slender andterminateinsmallbulbousenlargementscalled olfactory vesicles,fromwhichSupportingcellarise cilia--These cilia are very long and parallel toOlfactorythe epithelial surfacecell-- These cilia are nonmotile and respondAxonto odoriferous substances--theiraxonsunite insmall bundlestoformthefascicles oftheolfactorynerveShwanncell10
③ olfactory cells -They are bipolar neurons -Their nuclei lie below the nuclei of supporting cells -The apical dendrites are slender and terminate in small bulbous enlargements called olfactory vesicles, from which arise cilia -These cilia are very long and parallel to the epithelial surface - These cilia are nonmotile and respond to odoriferous substances -their axons unite in small bundles to form the fascicles of the olfactory nerve Olfactory vesicle Olfactory cilia Supporting cell Olfactory cell Axon Shwann cell 10