dissection worksheets

7/30/2019 Dissection Worksheets

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BDS1 ThethoracicskeletonThissessionisdesignedtofamiliarizeyouwiththethoracicskeleton.

1.Onaskeleton,identifythecomponentsofthethoraciccageandlistthemhere:

2.Whatisthethoracicinletandwhatisthethoracicoutlet?Whichstructuresdefine

theirboundaries?Whichpartsoftherespiratorysystemanddigestivesystempass

throughthethoracicinletandnamethreelargetubularstructuresthatpassthroughthe

outlet.

3.Identifyandnamethethreepartsofthesternum.

4.

Identify

the

costal

cartilages

and

the

costal

margin.

Which

ribs

do

not

have

a

direct

attachmentoftheircostalcartilagetothesternum?Whataretheseribscalled?Your

answershouldcontaintwodifferenttypesofrib.


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5.Examineathoracicvertebraandidentifythesuperiorandinferiorsurfaceofitsbody.

Identifythespinousandtransverseprocessesandthevertebralforamen.What

structurerunsthroughthevertebralforamen?

6.Examineatypicalribandidentifythehead,neck,tubercle,angle,costalgrooveand

body.Makesureyouknowwhicharethesuperiorandinferioraspectsoftherib.

7.Taketwothoracicvertebraeandatypicalribandexaminehowtheyarticulate

together.Wherearetherelevantarticularfacets?Iftheribyouareexaminingisthe8th

rib,withwhichvertebraewoulditarticulate?

8.Examinethefirstribandnotehowitdiffersfromtheotherribs.Noteitsrelationship

tothemanubriumandtotheclavicle.Doyouthinkthefirstribisverymobile?

9.Whatarethefunctionsofthethoraciccage?Rememberevenvertebratesthathave

nolungsstillhaveribs.

10.Discusswithinyourgroupsthemeaningofthefollowinganatomicalterms:

inferior,superior,ventral,dorsal,anterior,posterior,rostral,caudal,medial,lateral,

median,sagittal,parasagittal,coronal,transverse.


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BDS1 Intercostalspace,diaphragm,neuralcontrolofbreathingThissessionisdesignedtofamiliarizeyouwithbasicanatomyofthemembranesandmusclesthatlinethethoraciccavityandtheneuromuscularcontrolofbreathing

1.Onadissectedcadaveridentifyanintercostalspaceandobservetheorganisationof

muscles,nervesandbloodvesselsthatlieinthisspace. Listthesestructuresandtheir

spatialorganisationhere:

2.Whatisanintercostalnerve?Whatdoesitdo?Whatstructuresdoesitinnervate

(thereshouldbeatleast3componentstoyouranswer)?

3.Wherewouldyoufindthecellbodiesoftheaxonsthatyoufindinanintercostal

nerve(thereshouldbeatleast2componentstoyouranswer)?Atwhichsegmental

levels

would

these

cell

bodies

lie?


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4.Identifythediaphragmindissectedmaterial.Observetheorientationofthemuscle

fibres.Trytoobserveasbestyoucantheattachmentsofthediaphragmtothebody

wall.Listthoseattachmentshere:

5.Identifythemajortubularstructuresthatpenetratethediaphragm.Listthemhere

andeitherdescribeordrawthepositionsthattheypenetratethediaphragm.

Whatwillhappentothesestructureswhenthediaphragmcontracts?Doesthismake

functionalsense(thinkaboutthepressurechangesinthethorax,thedirectionofflow

withinthesestructuresandwhatyoudon'twanttohappentothisflow).

6.Identifytheinnervationofthediaphragm.Wherewouldyoufindthecellbodiesof

theaxonsthatarecontainedinthesenerves?Whatistherelationofthesenervestothe

fibrouspericardium?


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7.Identifythecentraltendonofthediaphragm.Identifytheattachmentofthefibrous

pericardiumtothecentraltendon(whyisitagoodideathatthepericardiumattaches

hereratherthanotherregionsofthediaphragm?).

8.Examinethesurfacesofthelungsandthethoraciccavityitself.Whereisthevisceral

pleuraandwhereistheparietalpleura?Whatisthenameofthecavitythatlies

betweenthesemembranesandwhatwouldyounormallyfindinthiscavity?Whatisthe

purposeofthepleuralmembranesandtheircontents?

9.Whatisthecostadiaphragmaticrecess?Ifyourdissectedorprosectedmaterial

allows,runyourhanddownthedomeofthediaphragmsothatyourfingertipsreach

themostinferiorextentofthecostadiaphragmaticrecess.Howfardownintothisspace

dothelungsthemselvesreach?

10.Yourbodyisabletomonitorthelevelsofoxygenandcarbondioxideinyourblood

andmodulateyourbreathingaccordingly.Whichbitofthebrainisresponsibleforco

ordinatingthismechanism?


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BDS1 TheairwaysandlungsThissessionisdesignedtofamiliarizeyouwiththebasicanatomyoftheairwaysandlungs

1.Usingmaterialfromeitheradissectedcadaverorpottedmaterialidentifythemajor

structuraldifferencesbetweenleftandrightlungs.Illustratethesedifferencesby

drawingmedialandlateralviewsofthetwolungsbelow.

2.

Grab

a

piece

of

lung

between

your

fingers,

squeeze

it

and

release.

What

happens?

Why?Whenyoutouchthelungslikethiswhatmaterialareyouactuallytouching?

3.

Examine

the

medial

surfaces

of

the

two

lungs.

At

their

centre

you

will

find

the

root

of

thelung.Whatmajorstructuresdofindintherootofthelung?Howwouldidentify

eachofthese?


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4.Drawadiagramtoillustratetherelationshipoftheparietalpleurawiththevisceral

pleuraattherootofthelung.

5.Frompottedmaterialexaminethetracheaandbronchialtrees.Identifytheleftand

rightmainbronchi.Howdotheydiffer?Whydotheydifferandwhatcanbea

consequenceofthisdifference?

6.Describeinnomorethanthreesentenceswhatdoyouunderstandbytheterm

bronchopulmonarysegment?Whyaretheyofanyclinicalrelevance?


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7.Identifyanddescribethestructuralfeaturesofthetracheaandbronchialtreesthat

helpmaintainthepatencyoftheairways.Whataspectofthisarchitectureallowsforthe

diameteroftheairwaystoberegulated?Howisthediameteroftheairwaysregulated

whichnervesandwhichmusclesachievethis(Idon'texpectapreciseanswerhere,just

ageneralanswer)?

8.Whathappensduringanasthmaattack?Howcanthisberelieved?o

9.Onahalfhead,identifythenasalandoralcavitiesandfindthethreesubdivisionsof

thepharynx nasopharynx,oropharynxandlaryngopharynx.


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10.Identifyanddrawtherelationshipofthelarynxtothepharynx.Youdonotneedto

knowthestructureofthelarynxindetailatthispoint,butyoushouldbeabletoidentify

theleaflikeepiglottisandthevocalchords.

11.Whatistheprimaryfunctionofthelarynx?Howdoesthelarynxcontributetothe

mechanismsofcoughingandsneezing?


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BDS1 TheheartThissessionisdesignedtofamiliarizeyouwiththebasicstructureoftheheartandassociatedgreatvessels.

1.Onaheartidentifythefollowing:

wallsofrightandleftatria

leftandrightauricle

wallsofrightandleftventricles

ascendingaorta

pulmonarytrunk

leftandrightpulmonaryarteries

leftandrightpulmonaryveins

inferiorandsuperiorvenacavae

theapexoftheheart(nexttowhichintercostalspacedoestheapexusuallylie)

2.Observetheanteriorviewoftheheartandonasimpleoutlinedrawwhatyoucansee

oftherightatrium,therightventricularwallandtheleftventricularwall.

3.Thewallofwhichchamberfillsmostoftheposteriorsurfaceoftheheart?


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4.Whichpartsoftheheartformitsdiaphragmaticsurface?

5.Examinetheproximalregionoftheascendingaortacarefully.Canyoufindanyblood

vesselsconnectedtothisregion?Howmany?Howaretheyrelatedtothepulmonary

trunk?Followthesebloodvesselsasfarasyoucanonthesurfaceoftheheart.

6.Examinethejunctionsbetweentheatriaandtheventriclesandthejunctions

betweenthetwoventricles.Youshouldbeabletoseethejunctionsarecharacterised

bygroovesinthesurfaceoftheheart.Suggestsomesimpledescriptiveanatomical

namesforthesegrooves.

7.Inthegroovesbetweentheatriaandtheventriclesyouwillprobablyfindfatdeposits

andalsosomebloodvessels.Trytoconnectthesebloodvesselstothevesselsyou

foundleavingtheproximalregionoftheaorta.


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8.Youshouldfindalargebloodvesselinthegroovebetweenleftatriumandleft

ventricleontheposteriorsurfaceoftheheart.Wheredoesthisvesseldraininto?

9.Examineheartsthathavebeendissectedtorevealtheinnerwallsoftheheart

chambers.Wheredoyoufind:

thepectinatemuscles?

thepapillarymuscles?

thefossaovalis?

trabeculaecarneae?

chordaetendineae?

10.Examinetheinnersurfaceoftherightatrium.Howmanyopeningscanyoufindinto

thisatrium?Whichvesselsdrainintotheseopenings?

11.Examinethestructureoftheatrioventricularvalvesandcomparethesewiththe

structureofthesemilunarvalvesthatyouwillfindattheentrancetothepulmonary

trunkandaorta.


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12.Whatistherelationshipoftheaorticvalvewiththebloodvesselsyoufoundleaving

theleavingthesurfaceoftheascendingaorta(point5above)?

13.Whichvalvesareopenduringatrialsystoleandwhichduringventricularsystole?At

whichpointinheartbeatwillmostbloodenterthevesselsthatleavethesurfaceofthe

ascendingaorta?Why?

14.Onadissectionofthemediastinumexaminethefibrouspericardium.Noteits

attachmenttothediaphragmandifpossibletothegreatvesselsastheyleavetheheart.

Whereistheparietalpericardium?Whereisthevisceralpericardium?Identifythe

pulmonaryarteriesandpulmonaryveinsintherootofthelungsifyoucan.


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BDS1MediastinumDR

Thissessionisdesignedtoillustratetheorganisationofthelargebloodvessels,tracheaandoesophagusinthesuperiormediastinum,thecontentsoftheposteriormediastinumandthegeneralorganisationofthesympatheticandparasympatheticinnervationtothethorax.

You will be provided with prosected thorax.

1. In the superior mediastinum find (in roughly anterior to posterior order (see

diagram):

superior vena cava, right and left brachiocephalic vein and their branches to

become subclavian and internal jugular veins

aortic arch and brachiocephalic artery and left common carotid and left

subclavian artery

pulmonary trunk branching into left and right pulmonary arteries

tracheaoesophagus

azygos vein draining into SVC

2. Try to follow the descending aorta and the oesophagus through the posterior

mediastinum to the point where they penetrate the diaphragm.


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3. Can you find the arterial branches from the descending aorta that supply the

intercostal spaces?


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4. Find the internal thoracic arteries on either side of the sternum and their

branches to the anterior intercostal spaces. From which arteries do the internal

thoracic arteries branch?

5. Try to find the azygos system of venous drainage on the right side of the posterior

thoracic cage and the hemiazygos system of drainage on the left side. Can you see

how these communicate across the midline? Remember the pattern can be quite

variable.


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6. Find the sympathetic trunk on the lateral aspects of the bodies of the thoracic

vertebrae. Can you see any periodic swellings along the length of the trunk? What

are these swellings and what do they contain? Do they contain neuronal cell bodies?

If so do these cell bodies have dendrites and do they receive synapses?

7. How is the sympathetic chain connected to the central nervous system? From

which segmental levels do these connections arise?

8. In general terms how does the sympathetic chain connect to the heart? Is it via

preganglionic axons or postganglionic axons?

9. Where would you find the neuronal cell bodies whose axons run in the vagusnerve?

10. Where would you find the synapses between the preganglionic and

postganglionic neurons of the vagus nerve that innervate the heart?

dissection worksheets

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