Chapter One: Introduction ANATOMICAL POSITION AND TERMS OF DIRECTION Whenstudyingthehumanbodyitis importanttoplacethe bodyin anatomicalposition.Anatomical a. _ a. _ positionisdescribedasthe body facingyou,feetplacedtogetherand flaton the floor.Theheadisheld erect,armsstraightbythesidewith palms facingforward.Allreferences tothe bodyaremadeasifthe bodyis inthis positionsowhenyoudescribe e. _ somethingasbeingabovesomething elseitisalwayswithrespecttothe () bodybeinginanatomicalposition. The relativepositionofthe partsof h.___ 1. _ thehumanbodyhasspecific terms. Superiormeansabovewhile ). ....lII('---:-1----'):----;-~.k.-- inferiormeansbelow.Medialrefers tobeingclosetothe midlinewhile lateralmeans totheside.Anterior orventralistothe frontwhile VI,\ e _ posteriorordorsalistothe back. I Superficialisnear thesurfacewhile deep meanstothecoreofthe body. When workingwith the limbs, proximalmeansclosertothetrunk whiledistal istothe ends ofthe extremities.Writethe directional termsinthespacesprovidedand color inthe arrowsinreferenceto theseterms.Notethatthese terms aresomewhatdifferentforfour leggedanimals. f.__ b.__ b.__ g._----- ~V? 1 .. \! )~ h.__ .. I I. l«=~ AnswerKey:a.Superior, b.Inferior, c.Lateral, d.Medial,e.Proximal, f.Distal,g.Anatomicalposition, h Posterior,i.Anterior,j.Dorsal, k.Ventral ChapterOne I mKAPeLAN(I·-Ical 3 Introduction ANATOMICAL PLANES OF THE BODY Manyspecimensinanatomyare sectionedsothatthe interiorofthe organorregion canbeexamined.It isimportantthatthe directionofthe cutisknownsothatthe proper orientationofthe specimenis known.Aheartlooks verydifferent ifitiscut along itslengthasopposed tohorizontally.Ahorizontalcut is knownasatransversesectionora crosssection.Acut thatdivides the bodyor anorganintoanteriorand posteriorpartsisacoronalsection orfrontalsection.Onethatdivides thestructureintoleftand rightparts isasagittalsection.Ifthe bodyis divideddirectlydownthe middlethe sectionisknownasamidsagittal section.Amidsagittalsectionis c. _ usuallyreserved fordividingthe bodyintotoequal leftand right parts.Ifanorgan (such astheeye)is sectionedintotwoequalpartssuch thatthereisaleftand righthalfthen this isknownasamediansection. Labeltheillustrationsand color in the appropriateplanes. a. _ AnswerKey:a.Frontal(coronal) plane, b. c. b.Transverse(cross-section) plane, c.Median (midsagittal) plane ChapterOne I KAPLA~. I 5 meulCa Introduction HIERARCHY OFTHEBODY These inturnmake uporganelles,which arepartofalarger,more complicatedsystemscalledcells.Cellsarethe structuraland functional Thehumanbodycanbestudiedatdifferentlevels.Organssuch asthe unitsoflife.Cellsareclusteredintotissues.Organsarediscreet units stomachcanbegroupedinto organsystems (digestivesystem) orcanbe made upoftwoor more tissuesand organsaregroupedinto organ studiedonasmaller scalelikethecellular level.Therankingofthese systemsthatcomposetheorganism.Labelthelevelsofthehierarchy levelsiscalledahierarchy.The smallest organizationalunitistheatom. and coloreachitem adifferentcolor. Individualatomsaregroupedinto largerstructurescalledmolecules. ~a. b. _ o g.----- c. ----- d. _ AnswerKey:a.Organism(human),b.Organsystem (respiratorysystem)c.Organ (lung),d.Tissue(epithelium),e.Organelle(cilia),f.Molecule,g.Atom,h.cells