lymphatic system-converted.pdf

lymphatic system

2. •Thelymphaticsystemispartofthecirculatory
systemandtheimmunesystem,comprisinga
networkoflymphaticvesselsthatcarryaclear
fluidcalledlymphunidirectionallytowardsthe
heart.

3. Removalofinterstitialfluidfromtissues
Absorptionof Fat: Lymph
vesselscalledlactealsarepresentinthelining
ofthesmallintestine.Whichabsorbfat.
TransportationofWBC
Immunefunction:Cellsinthelymphatic
systemreacttoantigenspresentedorfound
bythecells.

4. The four components of lymphatic system are:
1.LYMPH
2.LYMPH VESSEL
3.LYMPHOID TISSUE/ LYMPHOID ORGAN
4.LYMPHOCYTES and PHAGOCYTES

5. Aclearfluidcomposedmainlyofwater,
electrolytesandsomeplasmaproteins
Transportedinlymphaticpathwayfrom
lymphaticvesselstocollectingductsandend
disposedintovenousblood
Whenbloodcirculatesinhighpressure,the
fluid(plasma)portionseepsthroughthin
capillarywallsintosurroundingtissue.

6. Thisinterstitialfluidisreturnedtobloodthrough
wallsofvenules.
Theremainderentersanetworkofthinwalled
tubescalledlymphaticvesselsandnowiscalled
lymph.

7. Theflowoflymphinthethoracicductinan
averagerestingpersonusually
approximates100mlperhour.
Accompaniedbyanother25mlperhourin
otherlymphvessels.
Thetotallymphflowinthebodyisabout2
to3litresperday.

8. Lymphaticcapillaryrunparalleltobloodcapillaries
inallbodytissuesandallowdiffusionoffluidfrom
interstitialspacesintolymphaticpathway.
Structurallyidenticaltoveins-vesselwallcomposed
of3thinlayersoftissue,andcontainvalvesto
preventbackflow.
Theyformspecializedlymphaticorganscalled
lymphnodeswhichstoremacrophagesand
lymphocytestoeliminateforeignsubstanceinthe
lymph.

10. Thoracicductreturnslymphfromleftsideofthe
bodytoleftsubclavianvein,andRightlymphatic
ductreturnslymphfromrightpartofthebodyto
rightsubclavianvein.

11. Transportlymphawayfromtissues
Collectandfilterlymph(atthenodes)as
itcontinuestomovetowardlargervessels
calledcollectingducts.

12. Lymphaticorgansaredividedasprimarylymphatic
organsandsecondarylymphaticorgans:
1.PrimaryLymphaticOrgansareredbonemarrow
andthymusgland.TheredbonemarrowproduceT-
cellsinresponsetoanantigenandtheygetmatured
inthymusgland.
2.SecondaryLymphaticOrgansarelymphnodes,
spleen,lymphaticnodules.Thesearethesitesof
immuneresponses.

13. Bonemarrowisasemi-solidtissuefound
withinthespongyportionsofbones
Itistheprimarysiteofhaematopoiesis.
Itiscomposedofhematopoieticcells,
marrowadiposetissue,and
supportivestromalcells

14. Thethymusisanorganwithtwolobesthat
islocatedanteriortotheascendingaortaand
posteriortothesternum.

15. Eachlobesurroundedbyacapsuleand
dividedintolobules,whichareseparated
fromeachotherbystransofconnective
tissuecalledtrabeculae.

16. Eachlobuleorganizedinto2compartments:the
outercompartmentcortex,andtheinner
compartmentmedulla.
ThematurationofTcellsandmonocytestakes
placeinthemedullawhichissupportedby
epithelialcellsandmacrophagespresentinthe
thymus.
Inadditionitalsosecretehormonesuchas
thymosinwhichstimulatethedevelopmentof
antibodies.

17. Around600beanshapedlymphnodesare
locatedthroughoutthebody.
Lymphnodesfiltersubstancesthattravel
throughthelymphaticfluid,andcontain
lymphocytes(whitebloodcells)thathelpthe
bodyfightinfectionanddisease

18. Lymphnodecanbedividedinto3centric
regions:theCortex,theParacortexandthe
Medulla.
TheoutermostcortexcontainsBlymphocytes,
macrophagesandfolliculardendriticcells.
Beneathcortex,paracortexcontainsT
lymphocytes.
Medullacontainslymphoidcells,andplasmacells
whichactivelysecretsantibodies.

20. Filterationoflymph-lymphnodefilterand
purifythelymph(removecelldebris,virus,
fungietc)beforereturntothevenous
circulation
Trappingtheantigen-trapstheantigenand
presentsinfrontoflymphocytes
Productionoflymphocytes(maturation)
Phagocytosis

21. Thespleenisafist-sized
organintheupperleftsideof
abdomen,nexttothestomach
andbehindleftribs.
Itissurroundedbyacapsule
fromwhichanumberof
projections(trabeculae)
extendintointeriortoform
compartments.

23. Compartmentsareoftwotypes:theREDpulp
andtheWHITEpulp,separatedbyadiffuse
marginalzone.
Thewhitepulpsurroundsthebranchesof
splenicartery,formingPeriarterialLymphatc
Sheath(PALS)whichcontainsTlymphocytes.
Withintheredpulpthefollowingfunctionssuch
asremovalofdefectivebloodcellsandplatelets,
storageofplateletsforemergencyuse,and
productionofbloodcellsduringfetallifeetc.

24. Phagocytosis(destructionofRBCand
Platelets)
Storageofblood(approx350mlofbloodis
storedwhichcanbeusedincriticalconditions)
Erythropoiesis(infetus)
Immuneresponse(spleenomegalyincaseofany
infectionduetoactivatedTandBlymphocytes)

25. Theyareeggshapedmassesoflymphatictissues
differentfromlymphnodessincetheydonothave
capsules.
TheyarelocatedatthemucosalliningofGI,urinary,
respiratoryandreproductivetractsandalsoreferred
asMALT(mucosa-associatedlymphatictissue)
Thetonsils(inthethroat),thePeyerpatches(within
thesmallintestine),andthevermiformappendixare
examplesofMALT.

27. Thenomenclatureincorporates
location;therefore,MALTisunderstoodto
include
Gut-associatedlymphoidtissue(GALT),
Bronchialassociatedlymphoidtissue
(BALT)
Nose-associatedlymphoidtissue(NALT)
Vulvovaginal-associatedlymphoidtissue
(VALT).

28. T CELLS
B CELLS
MONOCYTES AND
MACROPHAGES/PHAGOCYTES
MAST CELLS
DENDRITIC CELLS: derived from monocytes and have
long branched projections similar to neurons.
GRANULOCYTIC CELLS: Neutrophil. Eosinophil,
Basophil

30. Waterandsolutescontinuallyfilteroutfrom
capillaryintointerstitialspace.Tobalancethis
outflow,fluidcontinuallyreentersbloodthrough
lymphaticsystem.
Fluid(lymph)isfilteredthroughlymphnodesto
removebacteria,abnormalcellsandotherforeign
materials.
Thisfluidisthentransportedbackintothe
bloodstreamviathelymphvessels.
Lymphonlymovesinonedirection,towardthe
heart.

32. Lymphedema:Itisaconditionof
localizedfluidretentionandtissueswellingcaused
byblocked/improperlymphaticsystem.
Themainsymptomisswellinginanarmorleg
thatmaybeaccompaniedbypainordiscomfort.

33. Theconditioncanbeinheritedorcanbecaused
byaninjurytolymphvesselornodesasaresult
oftreatmentofcancersuchasradiation,surgery
oraparasiticinfectioncalledfilariasis.
Lymphedema Filariasis

34. There'snocureforlymphedema.
Therapiesforlymphadema:
Exercises.Gentlecontractionofthemusclesinthe
armorlegcanhelpmovetheexcessfluidoutof
theswollenlimb.
Manuallymphdrainage
Compressionbandages
Compressiongarments