anatomy of respiratory students 211-02.pdf

anatomy

2. THE HUMAN RESPIRATORYSYSTEM
•Therespiratorysystemconsistsofthenose,
pharynx(throat),larynx(voicebox),trachea
(windpipe),bronchi,andlungs.

4. Structurally, the respiratory system consists of
two parts:
1.The upper respiratory system includes the
nose, nasal cavity, pharynx and associated
structures.
2.The lower respiratory system includes the
larynx, trachea, bronchi and lungs.

5. 1.Theconductingzoneconsistsofaseries
ofinterconnectingcavitiesandtubesboth
outsideandwithinthelungs.
Theseincludethenose,nasalcavity,pharynx,
larynx,trachea,bronchi,bronchioles,and
terminalbronchioles.Theirfunctionisto
filter,warm,andmoistenairandconductit
intothelungs

6. 2.Therespiratoryzoneconsistsoftubes
andtissueswithinthelungswheregas
exchangeoccurs.
Theseincludetherespiratorybronchioles,
alveolarducts,alveolarsacsandalveoli.(Gas
exchangeoccurinthesezone)

7. Respiratorymucosa
•Itisalayerofpseudostratifiedciliated
columnarepithelialcellsthatsecretemucus.
•Foundinnose,sinuses,pharynx,larynxand
trachea
•Mucuscantrapcontaminants
–Ciliamovemucusuptowardsmouth

9. NOSE
•Itprovidesanentranceforairinwhichairis
filteredbyhairsinsidethenostrils.
•Ithastwoportions:theexternaland
internal.
–Externalnares(choanae)-openingtoexterior
–Internalnaresopeningtopharynx

10. •Theexternalportionissupportedbya
frameworkofboneandcartilagecovered
withskinandlinedwithmucous
membrane.
•Theinternalportionisalargecavityinthe
skull,mergingwiththeexternalnose
anteriorlyandcommunicatingwiththe
throatposteriorly.

11. NASAL CAVITY
•Theentranceoftherespiratorysystemthatis
dividedintoanexternalportionandaninternal
portioncalledthenasalcavity.
•Interiorareaofthenose;linedwithasticky
mucousmembraneandcontainstinysurface
hairscalledcilia.Itdividedmediallybythe
nasalseptum.
•Particlestrappedinthemucusarecarriedto
thepharynxbyciliaryaction,swallowed,and
carriedtothestomachwheregastricjuice
destroysanymicroorganismsinthemucus.

12. •Theanteriorportionofthenasalcavityjust
insidethenostrils,calledthenasalvestibule,
issurroundedbycartilage.
•Thesuperiorpartofthenasalcavityis
surroundedbybone.
•Averticalpartition,thenasalseptum,divides
thenasalcavityintorightandleftsides.The
anteriorportionofthenasalseptumconsists
primarilyofhyalinecartilage.

15. PARANASAL SINUSES
•Fourbonesoftheskullcontainpairedairspaces
calledtheparanasalsinuses-frontal,ethmoidal,
sphenoidal,maxillary.
•Addresonancetovoice.
•Communicatewiththenasalcavitybyducts.
•Linedbypseudostratifiedciliatedcolumnar
epithelium.

17. PHARYNX
•Thepharynxisafunnel-shapedtube
about13cmlongthatstartsatthe
internalnaresandextendstothelevelof
thecricoidcartilage,themostinferior
cartilageofthelarynx.
•Thepharynxliesjustposteriortothe
nasalandoralcavities,superiortothe
larynx,andanteriortothecervical
vertebrae.
•Itisacommonpassagewayforair
andfood.

18. •Itswalliscomposedofskeletalmusclesand
islinedwithamucousmembrane.
•Themusclesoftheentirepharynxare
arrangedintwolayers,anoutercircular
layerandaninnerlongitudinallayer.
•Relaxedskeletalmuscleshelpkeepthe
pharynxpatentandcontractionofthe
skeletalmusclesassistsindeglutition
(swallowing).

19. •Pharynxisdividedintothreeregions
–Nasopharynx-uppermostportion
–Oropharynx-middleportion
–Laryngopharynx-lowermostportion

21. Nasopharynx
•Superior-mostregionofthepharynx.
•Coveredwithpseudostratifiedciliated
columnarepithelium.

22. •Location:
–posteriortothenasalcavity
–superiortothesoftpalate.
–lateralwallsofthenasopharynxconnecttothe
auditory/eustachiantubeswhichopenintomiddle
ear.
•Normally,onlyairpassesthrough.
•Materialfromtheoralcavityandoropharynxis
typicallyblockedfromenteringthe
nasopharynxbytheuvulaofsoftpalate,which
elevateswhenswallow.
•Posteriornasopharynxwallalsohousesa
singlepharyngealtonsil(commonlycalledthe
adenoids).

25. •Throughtheinternalnares,thenasopharynx
receivesairfromthenasalcavityalongwith
packagesofdust-ladenmucus.Theciliain
nasopharynxciliamovethemucusdown
towardthemostinferiorpartofthepharynx.
•Thenasopharynxalsoexchangessmall
amountsofairwiththeauditorytubesto
equalizeairpressurebetweenthepharynxand
themiddleear.

26. OROPHARYNX
•Themiddlepharyngealregion.
•Immediatelyposteriortotheoralcavity.
•Openstotheoralcavityviaanarchwaycalled
thefauces.

27. •Boundaries:
–superiorlyedgeofthesoftpalate.
–inferiorlythehyoidbone.
•Commonrespiratoryanddigestivepathway
throughwhichbothairandswallowedfood
anddrinkpass.
•Contains nonkeratinizedstratified
squamous epithelim.
•Lymphaticorgansprovidethefirstlineof
defenseagainstingestedorinhaledforeign
materials.
•Twopairsoftonsils,thepalatinetonsilsand
lingualtonsilsarefoundintheoropharynx.

29. LARYNGOPHARYNX
•Laryngopharynxorhypopharynx
•Inferior,narrowedregionofthepharynx.
•Boundaries
–Superiorly hyoid bone
•Inferior end it opens into the esophagus (food
tube) posteriorly and the larynx (voice box)
anteriorly.
•Lined with a nonkeratinizedstratified
squamous epithelium.
•Permitspassageofbothfoodandair.

32. Lower Respiratory Tract
It includes conducting airway and respiratory
portion
Composed of trachea, bronchial tree, lungs,
alveolus and alveoli.
Alveoli is the functional unit of lungs.
•Conducting airways (pharynx, trachea,
bronchi, up to terminal bronchioles).
•Respiratory portion of the respiratory system
(respiratory bronchioles, alveolar ducts, and
alveoli).

33. Larynx
•Larynx or Voice box is a short, cylindrical
airway ends in the trachea. It is about 5 cm
long.
•Boundaries:
–Superiorly it attaches to
hyoid bone and opens into th
laryngopharynx
–Inferiorly trachea.
–Posteriorly esophagus

34. •Position: It lies in the midline of the neck
anterior to the esophagus and the fourth
through sixth cervical vertebrae (C4–C6).

35. •Itconductsairintothelowerrespiratorytract.
•Producessounds.
•Itiscomposedofaframeworkofninepiecesof
cartilage(threeindividualpiecesandthree
cartilagepairs)thatareheldinplaceby
ligamentsandmuscles.
•Exceptfortheepiglottis,alllaryngealcartilages
arehyalinecartilages.
•Musclesoflarynx:extrinsicmusclesand
intrinsicmuscles.
•Theextrinsicmusclesofthelarynxconnectthe
cartilagestootherstructuresinthethroat.
•Theintrinsicmusclesconnectthecartilagesto
oneanother.

36. Cartilages of larynx:
•Nine c-rings of cartilage form a framework of the
larynx.
•3 unpaired
•3 paired
•3 unpaired cartilages
–Thyroid cartilage
–Cricoid cartilage
–Epiglottis
•3 paired cartilages
–Arytenoid
–Cuneiform
–Corniculatecartilages

38. •Thyroidcartilage–(Adam’sapple)consistsof
twofusedplatesofhyalinecartilagethatform
theanteriorwallofthelarynxandgiveita
triangularshape.Theligamentthatconnects
thethyroidcartilagetothehyoidboneiscalled
thethyrohyoidmembrane.
•Cricoidcartilage–ring-shaped,hyaline
cartilagethatformstheinferiorwallofthe
larynx.
•Epiglottis –large, leaf shaped piece of elastic
cartilage that is covered with epithelium.

40. •Arytenoidcartilages–aretriangularpieces
ofmostlyhyalinecartilagelocatedatthe
posterior,superiorborderofthecricoid
cartilage.Theyformsynovialjointswiththe
cricoidcartilageandhaveawiderangeof
mobility.
•Cuneiformcartilages-club-shapedelastic
cartilagesanteriortothecorniculatecartilages,
supportthevocalfoldsandlateralaspectsof
theepiglottis.
•Corniculatecartilages-horn-shapedpiecesof
elasticcartilage,arelocatedatthetopofeach
arytenoidcartilage

41. EpitheliumofLarynx
•Theliningofthelarynxsuperiortothevocal
foldsisnonkeratinizedstratifiedsquamous
epithelium.Theliningofthelarynxinferior
tothevocalfoldsispseudostratifiedciliated
columnarepitheliumconsistingofciliated
columnarcells,gobletcells,andbasalcells.
•Themucusproducedbythegobletcells
helpstotrapdustwhichisnotremovedin
theupperpassages.

42. Vocal folds
•Themucousmembraneof
thelarynxformstwopairs
offolds.Asuperiorpair
calledtheventricularfolds
(falsevocalcords)andan
inferiorpaircalledthe
vocalfolds(truevocal
cords).
•Thespacebetweenthe
ventricularfoldsisknown
astherimavestibuli.

43. Vocal Folds

44. •Vocalcordscontainelasticfibersandare
responsibleforvocalsounds,whichare
createdwhenairisforcedbetweenthese
folds,causingthemtovibratefromsideto
side.Thisactiongeneratessoundwaves,
whichcanbeformedintowordsby
changingtheshapesofthepharynxandoral
cavityandbyusingtongueandlips.

45. •Glottis–a triangular slit opening containing
between the true vocal cords. Its closure
helps to prevent food or liquid from entering
the trachea.
Glottis

46. Bloodsupplyoflarynx
•Bloodissuppliedtothelarynxbythe
superiorandinferiorlaryngealarteriesand
drainedbythethyroidveins,whichjointhe
internaljugularvein.
Nervesupplyoflarynx
•Theparasympatheticnervesupplyisfrom
thesuperiorlaryngealandrecurrent
laryngealnerves,whicharebranchesofthe
vagusnerves,andthesympatheticnerves
arefromthesuperiorcervicalganglia,one
oneachside

47. Epiglottis
•Theepiglottisisalarge,leafshapedpieceof
elasticcartilagethatiscoveredwithepithelium
•The“stem”oftheepiglottisisthetaperedinferior
portionthatisattachedtotheanteriorrimofthe
thyroidcartilageandhyoidbone.
•Thebroadsuperior“leaf”portionoftheepiglottis
isunattachedandisfreetomoveupanddown
likeatrapdoor.Preventsfoodanddrinkfrom
enteringairwaywhenswallowing

48. Parts of larynx
•Vocal cords
•Glottis
•Epiglottis
•Subglottis
•Supraglottis

49. TRACHEA

50. Trachea
Flexiblecylindricaltube-Sizeis4–5inlong&1indiameter,
itisalsocalledwindpipe.Linedbyciliatedpseudo
stratifiedcolumnarepithelium.
•Extendsthroughthemediastinumandliesanteriortothe
esophagusandinferiortothelarynx.
•Anteriorandlateralwallsofthetracheasupportedby15to
20C-shapedtrachealcartilages.
•Cartilageproviderigiditytothetrachealwall
•Posteriorpartoftubelinedbytrachealismuscle
Layers of trachea:
–Innermost layer (mucosa)= pseudostratified
columnar with cilia & goblet cells
–outer layer (submucosa)= loose connective tissue &
mucous glands

51. •Atthelevelofthesternalangle,thetracheadivides
intotwosmallertubes,calledtherightandleft
primarybronchi.
•Eachprimarybronchusprojectslaterallytoward
eachlung.
•Theinferiortrachealcartilageseparatesthe
primarybronchiandformsaninternalridgecalled
thecarina.

54. Bronchial tree
Itisahighlybranchedsystemofair-conductingpassagesthat
originatefromtheleftandrightprimarybronchi.
Incompleteringsofhyalinecartilagesupportthewallsofthe
primarybronchitoensurethattheyremainopen.
Rightprimarybronchusisshorter,wider,andmorevertical
thantheleftprimarybronchus.
•Theleftlunghastwosecondarybronchi.Therightlunghas
threesecondarybronchi.
•Theyfurtherdivideintotertiarybronchi.

56. •Primarybronchisupplyeachlung
•Secondarybronchisupplyeachlobeofthelungs(3
right+2left)
•Tertiarybronchisplitsintosuccessivesetsof
Intralobularbronchiolesthatsupplyeach
bronchopulmonarysegment(right=10,left=8)
•BronchiolessplitintoTerminalbronchiolesand
thesesplitintoRespiratoryBronchioles
•RespiratoryBronchiolessplitsintomultipleAlveolar
ductswhichendinanAlveolarsac

57. •Successivebranchingreducesthenumber
ofcartilagedecreasesandthenumberof
smoothmuscleincreases,thisallowsfor
variationinairwaydiameter,during
exertionandalsosympatheticand
parasympathetic reactions.
(Bronchodilation,bronchoconstriction)
•Theepithelialcellsgraduallychangesfrom
ciliatedpseudostratifiedcolumnar
epitheliumtosimplecuboidal
epitheliuminterminalbronchioles

58. ALVEOLI

59. •Lungscontainsmallsaccularoutpocketingcalledalveoli.
•Theyhaveathinwallspecializedtopromotediffusionof
gasesbetweenthealveolusandthebloodinthe
pulmonarycapillaries.
•Gasexchangecantakeplaceintherespiratory
bronchiolesandalveolarductsaswellasinthealveoli,
(range:274–790million).Thespongynatureofthelung
isduetothepackingofmillionsofalveolitogether.

60. Cells in Alveolus
1.TypeIalveolarcells–simplesquamouscells
wheregasexchangeoccurs
2.TypeIIalveolarcells(septalcells)–freesurface
hasmicrovilli–secretealveolarfluidcontaining
surfactant(reducessurfacetension).Hydrophilic
regionandhydrophobicregion)
3.Alveolardustcells–wanderingmacrophages
removedebris

62. Anatomy of the Lungs
•Lungoccupiesmostofthespacewithinthethoraciccavity.
Ithasaconicalshape.
•Towardthemidline,thelungsareseparatedfromeach
otherbythemediastinumandthisiscalledthe
mediastinalsurface
•Themedialaspectofeachlungandthesiteofentranceor
exitarecalledthehilumoflung.
•The structures connecting lung to the mediastinum are
called Root of the lung, it includes
–Bronchus ( Rtand Lt)
–Bronchial vessels
–Pulmonary artery
–2 Pulmonary veins
–Pulmonary nerve plexuses
–Bronchopulmonarylymph nodes and lymphatics.

63. Coastal and Mediastinal
Surfaces of Lungs

65. Costal surfaceof the lung.
•Therelativelybroad,rounded
surfaceincontactwiththe
thoracicwalliscalledthecostal
surfaceofthelung.
•Thelungsextendlaterally
fromthehearttotheribson
bothsidesofthechestand
continueposteriorlytoward
thespine.

66. •Thesuperiorendofeachlungformingthepointof
theconeandtheinferiorendformingthebase.
•Thesuperiorendofthelungsnarrowstoa
roundedtipknownastheapex.
•Theapexprojectssuperiorlytoapointthatis
slightlysuperiorandposteriortotheclavicle.
•Theinferiorendofthelungs,knownasthebase.

67. Left lung
•Divided into 2 lobes by oblique fissure
•Smaller than the right lung
•Cardiac notchaccommodates the heart
•Weight-left lung -550 gms
Right lung
•Divided into 3 lobes by oblique and horizontal
fissure
•Located more superiorly in the body due to liver
on right side
•Weight-right lung -600 gms

69. Right lung
•Superior lobe
1.Apical segment
2.Posterior segment
3.Anterior segment
•Middle lobe
4.Lateral segment
5.Medial segment
•Inferior lobe
6.Superior segment
7.Medial-basal segment
8.Anterior-basal segment
9.Lateral-basal segment
10.Posterior-basal
segment
Left lung
•Superior lobe
1.Apico-posterior
segment(merger of "apical"
and "posterior")
2.Anterior segment
•Lingulaof superior lobe
3.Inferior lingularsegment
4.Superior lingularsegment
•Inferior lobe
5.Superior segment
6.Anteromedialbasal segment
(merger of "anterior basal"
and "medial basal")
7.Posterior basal segment
8.Lateral basal segment

72. Pleura and PleuralCavity
Theribcageisseparatedfromthelungbyatwo-
layeredmembranouscoatingcalledthepleura.
Thepotentialspacebetweentheserousmembrane
layersisapleuralcavity.
•Thepleuralmembranesproduceathin,serous
pleuralfluidthatcirculatesinthepleuralcavity
andactsasalubricant,ensuringminimalfriction
duringbreathing.

74. •Theoutersurfaceofeachlungandtheadjacent
internalthoracicwallarelinedbyaserous
membranecalledpleura.
•Theoutersurfaceofeachlungistightlycoveredby
thevisceralpleura.
•whiletheinternalthoracicwalls,thelateralsurfaces
ofthemediastinum,andthesuperiorsurfaceofthe
diaphragmarelinedbytheparietalpleura.
•Theparietalandvisceralpleurallayersare
continuousatthehilumofeachlung.

75. BloodsupplyofLungs
•Pulmonarycirculation–Suppliesdeoxygenatedblood
pumpedfromtherightventricleanditiscarriedby
pulmonaryarteries.Whenbloodpassesthroughthe
capillariesthealveolibecomesoxygenated.
•Bronchialcirculation–Suppliesoxygenatedblood
pumpedfromtheleftventricleanditiscarriedby
bronchialarteries.Thiscirculationisotherwisecalled
systemiccirculation.Thebronchialarteriessupplyblood
tothebronchiandconnectivetissueofthelungs.They
travelwithandbranchwiththebronchi,endingaboutat
theleveloftherespiratorybronchioles.Theyanastomose
withthebranchesofthepulmonaryarteries
Pulmonaryarteries,thebronchialarteriessupplynutrition
tothelungs.

77. A.Right clavicle
B.Right scapula
C.Right fourth anterior rib
D.Right eighth rib
E.Right costophrenic angle
F.Left lung apex
G.Aortic arch
H.Hilum
I.Heart
J.Left lung base
K.Right hemidiaphragm
(white arrow).