Midterm iStudy iGuide
Chapter i1—The iCell
1. Cells ibecome ispecialized ithrough ithe iprocess iof idifferentiation/maturation.
2. The ieight ispecialized icellular ifunctions iare:
a. Movement, iconductivity, imetabolic iabsorption, isecretion, iexcretion,
irespiration, ireproduction iand icommunication.
3. The ieukaryotic icell iconsists iof ithree igeneral icomponents: ithe iplasma imembrane, ithe
icytoplasm iand ithe iintracellular iorganelles.
4. The inucleus iis ithe ilargest imembrane-bound iorganelle iand iis iusually ifound iin ithe
icell’s icenter.
a. The ichief ifunctions iof ithe inucleus iare icell idivision iand icontrol iof igenetic
iinformation.
5. The icytoplasm ior icytoplasm imatrix iis ian iaqueous isolution iknown ias icystol, ithat ifills
ithe ispace ibetween ithe inucleus iand ithe iplasma imembrane.
6. The iorganelles iare isuspended iin ithe icytoplasm iand iare ienclosed iin ibiologic
imembranes.
7. The iER iis ia inetwork iof itubular ichannels i(cisternae) ithat iextend ithroughout ithe
iouter inuclear imembrane.
a. It ispecializes iin ithe isynthesis iand itransport iof iprotein iand ilipid icomponents
iof imost iof ithe iorganelles.
b. The imost iimportant ifunction iof ithe iER iis iprotein ifolding iand isensing icell
istress.
8. The iGolgi icomplex iis ia inetwork iof ismooth imembranes iand ivesicles ilocated inear ithe
inucleus.
a. Responsible ifor iprocessing iand ipackaging iproteins iinto isecretory ivesicles
ithat ibreak iaway ifrom ithe iGolgi icomplex iand imigrate ito ia ivariety iof
iintracellular iand iextracellular idestinations, iincluding ithe iplasma imembrane.
9. Lysosomes iare isaclike istructures ithat ioriginate ifrom ithe iGolgi icomplex iand icontain
idigestive ienzymes.
a. These ienzymes iare iresponsible ifor idigesting imost icellular isubstances
icompletely ito itheir ibasic icomponents, isuch ias iamino iacids, ifatty iacids, iand
icarbohydrates.
b. Peroxisomes iare isimilar ito ilysosomes ibut icontain iseveral ioxidative ienzymes
isuch ias icatalase iand iurate ioxidase.
10. Mitochondria iare ifound iin igreat inumbers iin imost icells iand iare iresponsible ifor
icellular irespiration iand ienergy iproduction.
a. The ienzymes iof ithe irespiratory ichain i(electron-transport ichain), ifound iin ithe
iinner imembrane iof ithe imitochondria, igenerate imost ithe icell’s iATP i(energy).
11. Vaults iare icytoplasmic iorganelles ialso icalled iribonucleo-proteins.
a. Think iof ithem ias i“trucks” icarrying imRNA ifrom ithe inucleus ito ithe iribosomal
isites iof iprotein isynthesis.
12. The icytoskeleton iis ithe ibone iand imuscle iof ithe icell.
, a. The iinternal iskeleton iis icomposed iof ia inetwork iof iprotein ifilaments iincluding
imicrotubules iand iactin ifilaments.
13. Plasma imembrane: ithe iplasma imembrane iencloses ithe icell iand iby icontrolling ithe
imovement iof isubstances iacross iit, iexerts ia ipowerful iinfluence ion imetabolic
ipathways.
a. The iplasma imembrane iis ia ibilayer iof ilipids iand iproteins inot iuniformly
idistributed ibut ican iseparate iinto idiscrete iunits icalled i microdomains.
b. Membrane ifunctions iare idetermined ilargely iby iproteins iand itheir ifunctions
iinclude:
i. Recognition iand ibinding ireceptors ifor isubstances imoving iin iand iout
iof ithe icell
ii. Pores ior itransport ichannels
iii. Enzymes ithat idrive iactive ipumps
iv. Cell isurface imarkers, isuch ias iglycoproteins
v. Cell iadhesion imolecules
vi. Catalysts iof ichemical ireactions
c. The icarbohydrates icontained iwithin ithe iplasma imembrane iare igenerally
ibound ito imembrane iproteins.
14. Polypeptides iare iproteins imade iup iof iamino iacids iand iare ithe imajor iworkhorses iof
ithe icell.
a. Cellular ireceptors iare iprotein imolecules ion ithe iplasma imembrane, iin ithe
icytoplasm ior iin ithe inucleus ithat iare icapable iof irecognizing iand ibinding
ismaller imolecules icalled i ligands.
i. Ligand ireceptor icomplex iinitiates ia iseries iof iprotein iinteractions,
icausing iadenylyl icyclase ito icatalyze ithe itransformation iof icellular iATP
ito imessenger imolecules ithat istimulate ispecific iresponses iwithin ithe
icell.
b. A ifield icalled iproteomics iis ithe istudy iof ithe iproteome ior ientire iset iof iproteins
iexpressed iby ia igenome—from isynthesis, itranslocation iand imedication, ito
itheir irole iin ia istaggering inumber iof idiseases.
15. Cell-to-cell iadhesions iare iformed ion iplasma imembranes, iallowing ithe iformation iof
itissues iand iorgans. iCells iare iheld itogether iby ithree idifferent imeans:
a. The iextracellular imembrane
i. This iincludes ithree itypes iof iprotein ifibers iincluding icollagen, ielastin
iand ifibronectin. iThese ithree ihelp iregulate icell igrowth iand
idifferentiation.
b. Cell iadhesion imolecules iin ithe icell’s iplasma imembrane
c. Specialized icell ijunctions
i. There iare ithree imain itypes iof icell ijunctions iwhich iinclude
idesmosomes, itight ijunctions iand igap ijunctions.
16. The ibasement imembrane ior iaka ibasal ilamina iis ia ithin ilayer iof iconnective itissue
iunderlying ithe iepithelium iof i many iorgans.
17. Cells icommunicate iin ithree imain iways:
, a. They idisplay iplasma imembrane-bound isignaling imolecules i(receptors) ithat
iaffect ithe icell iitself iand iother icells iin idirect iphysical icontact.
b. They iactivate ireceptor iproteins iinside ithe itarget icell iand ithe isignal imolecule
ihas ito ienter ithe icell ito ibind ito ithem.
c. They iform iprotein ichannels i(gap ijunctions) ithat idirectly icoordinate ithe
iactivities iof iadjacent icells.
18. Primary imodes iof iintercellular isignaling iare icontact-dependent, iparacrine,
ihormonal, ineurohormal iand ineurotransmitter.
19. Signal itransduction iinvolves isignals ior iinstructions ifrom iextracellular ichemical
imessengers ithat iare iconveyed ito ithe icell’s iinterior ifor iexecution.
a. Signal itransduction ipathways ihave iseveral iimportant ifunctions iincluding
iphysically itransferring ithe isignal iaround ithe icell, iamplifying ithe isignal,
idistributing ithe isignal, iand imodulating ithe isignal.
20. The ichemical itasks iof imaintaining iessential icellular ifunctions iare ireferred ito ias
cellular imetabolism.
a. Anabolism iis ithe ienergy-using iprocess iof imetabolism.
b. Catabolism iis ithe ienergy-releasing iprocess.
21. Endocytosis iis ia icellular iinternalizing iprocess iwhere ia isection iof ithe iplasma
imembrane ienfolds isubstances ifrom ioutside ithe icell, iinvaginates iand iseparates ifrom
ithe iplasma imembrane iforming ia ivesicle ithat imoves iinside ithe icell. iIt ican ibe idivided
iin ito ifour icategories:
a. Clatherin-mediated iendocytosis
b. Caveolae-mediated iendocytosis
c. Macropinocystosis
d. Phagocytosis
22. Diffusion iis ithe ipassive imovement iof ia isolute ifrom ian iarea iof ihigher isolute
iconcentration ito ian iarea iof ilower isolute iconcentration.
23. Hydrostatic ipressure iis ithe imechanical iforce iof iwater ipushing iagainst icellular
imembranes.
24. Osmosis iis ithe imovement iof iwater iacross ia isemipermeable imembrane ifrom ia
iregion iof ilower isolute iconcentration ito ia iregion iof ihigher isolute iconcentration.
a. The iamount iof ihydrostatic ipressure irequired ito ioppose ithe iosmotic
imovement iof iwater iis icalled ithe iosmotic ipressure iof ithe isolution.
b. The ioverall iosmotic ieffect iof icolloids isuch ias iplasma iproteins iis icalled ithe
oncotic ipressure/colloid ipressure.
Chapter i2: iAltered iCellular iand iTissue iBiology
1. Injury ito icells iand itheir isurrounding ienvironment icalled ithe iextracellular imatrix
i(ECM) ileads ito itissue iand iorgan iinjury. iCellular iadaption iis ian ialteration ithat ienables
ithe icell ito imaintain ia isteady istate idespite ithe iadverse iconditions.
2. Atrophy iis ia idecrease iis icellular isize. iThe imechanisms iprobably iinclude idecreased
iprotein isynthesis, iincreased iprotein icatabolism ior iboth.
3. Hypertrophy iis ian iincrease iin ithe isize iof icells icaused iby iincreased iwork idemands
ior ihormonal istimulation.
a. This ican ieither ibe iphysiologic ior ipathologic.
, b. Amounts iof iprotein iin ithe iplasma imembrane, iER, imicrofilaments iand
imitochondria iare iincreased.
4. Hyperplasia iis ian iincrease iin ithe inumber iof icells icaused iby ian iincreased irate iof
icellular idivision.
a. Compensatory ihyperplasia ienables icertain iorgans ito iregenerate i(like ithe
iliver).
b. Hormonal ihyperplasia iis istimulated iby ihormones ito ireplace ilost itissue ior
isupport inew igrowth i(pregnancy).
c. Pathologic ihyperplasia iis ithe iabnormal iproliferation iof inormal icells iin
iresponse ito iexcessive ihormonal istimulation iof igrowth ifactors ion itarget icells.
5. Dysplasia i(atypical ihyperplasia) iis ian iabnormal ichange iin ithe isize, ishape iand
iorganization iof imature itissue icells.
6. Metaplasia iis ithe ireversible ireplacement iof ione imature icell itype iby ianother iless
imature icell itype.
a. Thought ito idevelop ifrom ia ireprogramming iof istem icells iexisting iin imost
iepithelia ior iof iundifferentiated imesenchyme icells iin iconnective itissue.
7. Injury ito icells iand ithe iECM ileads ito iinjury iof itissues iand iorgans, iultimately
idetermining ithe istructural ipatterns iof idisease. iCells imay irecover i(reversible) ior
imay idie i(irreversible).
a. Injury iis icaused iby ia ilack iof ioxygen, ifree iradicals, icaustic ior itoxic ichemicals,
iinfections iagents, iunintentional iand iintentional iinjury; iinflammatory iand
iimmune iresponses, igenetic ifacts, iinsufficient inutrients, ior iphysical itrauma
ifrom iother imeans.
b. Cell iinjury ican iby iacute ior ichronic iand iit ican ibe ireversible ior iirreversible. iIt
ican iinvolve inecrosis, iapoptosis, iautophagy, iaccumulation ior ipathologic
icalcification.
8. There iare ifour ibiochemical ithemes ithat iare iimportant ito icell iinjury:
a. Depletion iof iATP
b. Decreased ilevels iof ioxygen iand iincreased ilevels iof iocygen-derived ifree
iradicals
c. Increased iconcentration iof iintracellular icalcium iand iloss iof icalcium isteady
istate
d. Defects iin ithe imembrane ipermeability.
9. The iinitial iinsult iin ihypoxic iinjury iis iusually iischemia—the icessation iof iblood iflow
iinto ivessels ithat isupply ithe icell iwith ioxygen iand inutrients.
10. An iimportant imechanism iof imembrane idamage iis iinjury icaused iby ifree iradical
iincluding ioxidative istress. iFree iradicals iare idifficult ito icontrol iand iinitiate ichain
ireactions. iFree iradical ican icause:
a. Lipid iperoxidation ior ithe idestruction iof iunsaturated ifatty iacids
b. Alterations iof iproteins
c. Alterations iin iDNA
11. The iinitial iinsult iin ichemical iinjury iis idamage ior idestruction iof ithe iplasma
imembrane. iExamples iof ichemical iagents ithat icause icellular iinjury iinclude ilead,
icarbon imonoxide, iethanol, imercury iand istreet idrugs.
Chapter i1—The iCell
1. Cells ibecome ispecialized ithrough ithe iprocess iof idifferentiation/maturation.
2. The ieight ispecialized icellular ifunctions iare:
a. Movement, iconductivity, imetabolic iabsorption, isecretion, iexcretion,
irespiration, ireproduction iand icommunication.
3. The ieukaryotic icell iconsists iof ithree igeneral icomponents: ithe iplasma imembrane, ithe
icytoplasm iand ithe iintracellular iorganelles.
4. The inucleus iis ithe ilargest imembrane-bound iorganelle iand iis iusually ifound iin ithe
icell’s icenter.
a. The ichief ifunctions iof ithe inucleus iare icell idivision iand icontrol iof igenetic
iinformation.
5. The icytoplasm ior icytoplasm imatrix iis ian iaqueous isolution iknown ias icystol, ithat ifills
ithe ispace ibetween ithe inucleus iand ithe iplasma imembrane.
6. The iorganelles iare isuspended iin ithe icytoplasm iand iare ienclosed iin ibiologic
imembranes.
7. The iER iis ia inetwork iof itubular ichannels i(cisternae) ithat iextend ithroughout ithe
iouter inuclear imembrane.
a. It ispecializes iin ithe isynthesis iand itransport iof iprotein iand ilipid icomponents
iof imost iof ithe iorganelles.
b. The imost iimportant ifunction iof ithe iER iis iprotein ifolding iand isensing icell
istress.
8. The iGolgi icomplex iis ia inetwork iof ismooth imembranes iand ivesicles ilocated inear ithe
inucleus.
a. Responsible ifor iprocessing iand ipackaging iproteins iinto isecretory ivesicles
ithat ibreak iaway ifrom ithe iGolgi icomplex iand imigrate ito ia ivariety iof
iintracellular iand iextracellular idestinations, iincluding ithe iplasma imembrane.
9. Lysosomes iare isaclike istructures ithat ioriginate ifrom ithe iGolgi icomplex iand icontain
idigestive ienzymes.
a. These ienzymes iare iresponsible ifor idigesting imost icellular isubstances
icompletely ito itheir ibasic icomponents, isuch ias iamino iacids, ifatty iacids, iand
icarbohydrates.
b. Peroxisomes iare isimilar ito ilysosomes ibut icontain iseveral ioxidative ienzymes
isuch ias icatalase iand iurate ioxidase.
10. Mitochondria iare ifound iin igreat inumbers iin imost icells iand iare iresponsible ifor
icellular irespiration iand ienergy iproduction.
a. The ienzymes iof ithe irespiratory ichain i(electron-transport ichain), ifound iin ithe
iinner imembrane iof ithe imitochondria, igenerate imost ithe icell’s iATP i(energy).
11. Vaults iare icytoplasmic iorganelles ialso icalled iribonucleo-proteins.
a. Think iof ithem ias i“trucks” icarrying imRNA ifrom ithe inucleus ito ithe iribosomal
isites iof iprotein isynthesis.
12. The icytoskeleton iis ithe ibone iand imuscle iof ithe icell.
, a. The iinternal iskeleton iis icomposed iof ia inetwork iof iprotein ifilaments iincluding
imicrotubules iand iactin ifilaments.
13. Plasma imembrane: ithe iplasma imembrane iencloses ithe icell iand iby icontrolling ithe
imovement iof isubstances iacross iit, iexerts ia ipowerful iinfluence ion imetabolic
ipathways.
a. The iplasma imembrane iis ia ibilayer iof ilipids iand iproteins inot iuniformly
idistributed ibut ican iseparate iinto idiscrete iunits icalled i microdomains.
b. Membrane ifunctions iare idetermined ilargely iby iproteins iand itheir ifunctions
iinclude:
i. Recognition iand ibinding ireceptors ifor isubstances imoving iin iand iout
iof ithe icell
ii. Pores ior itransport ichannels
iii. Enzymes ithat idrive iactive ipumps
iv. Cell isurface imarkers, isuch ias iglycoproteins
v. Cell iadhesion imolecules
vi. Catalysts iof ichemical ireactions
c. The icarbohydrates icontained iwithin ithe iplasma imembrane iare igenerally
ibound ito imembrane iproteins.
14. Polypeptides iare iproteins imade iup iof iamino iacids iand iare ithe imajor iworkhorses iof
ithe icell.
a. Cellular ireceptors iare iprotein imolecules ion ithe iplasma imembrane, iin ithe
icytoplasm ior iin ithe inucleus ithat iare icapable iof irecognizing iand ibinding
ismaller imolecules icalled i ligands.
i. Ligand ireceptor icomplex iinitiates ia iseries iof iprotein iinteractions,
icausing iadenylyl icyclase ito icatalyze ithe itransformation iof icellular iATP
ito imessenger imolecules ithat istimulate ispecific iresponses iwithin ithe
icell.
b. A ifield icalled iproteomics iis ithe istudy iof ithe iproteome ior ientire iset iof iproteins
iexpressed iby ia igenome—from isynthesis, itranslocation iand imedication, ito
itheir irole iin ia istaggering inumber iof idiseases.
15. Cell-to-cell iadhesions iare iformed ion iplasma imembranes, iallowing ithe iformation iof
itissues iand iorgans. iCells iare iheld itogether iby ithree idifferent imeans:
a. The iextracellular imembrane
i. This iincludes ithree itypes iof iprotein ifibers iincluding icollagen, ielastin
iand ifibronectin. iThese ithree ihelp iregulate icell igrowth iand
idifferentiation.
b. Cell iadhesion imolecules iin ithe icell’s iplasma imembrane
c. Specialized icell ijunctions
i. There iare ithree imain itypes iof icell ijunctions iwhich iinclude
idesmosomes, itight ijunctions iand igap ijunctions.
16. The ibasement imembrane ior iaka ibasal ilamina iis ia ithin ilayer iof iconnective itissue
iunderlying ithe iepithelium iof i many iorgans.
17. Cells icommunicate iin ithree imain iways:
, a. They idisplay iplasma imembrane-bound isignaling imolecules i(receptors) ithat
iaffect ithe icell iitself iand iother icells iin idirect iphysical icontact.
b. They iactivate ireceptor iproteins iinside ithe itarget icell iand ithe isignal imolecule
ihas ito ienter ithe icell ito ibind ito ithem.
c. They iform iprotein ichannels i(gap ijunctions) ithat idirectly icoordinate ithe
iactivities iof iadjacent icells.
18. Primary imodes iof iintercellular isignaling iare icontact-dependent, iparacrine,
ihormonal, ineurohormal iand ineurotransmitter.
19. Signal itransduction iinvolves isignals ior iinstructions ifrom iextracellular ichemical
imessengers ithat iare iconveyed ito ithe icell’s iinterior ifor iexecution.
a. Signal itransduction ipathways ihave iseveral iimportant ifunctions iincluding
iphysically itransferring ithe isignal iaround ithe icell, iamplifying ithe isignal,
idistributing ithe isignal, iand imodulating ithe isignal.
20. The ichemical itasks iof imaintaining iessential icellular ifunctions iare ireferred ito ias
cellular imetabolism.
a. Anabolism iis ithe ienergy-using iprocess iof imetabolism.
b. Catabolism iis ithe ienergy-releasing iprocess.
21. Endocytosis iis ia icellular iinternalizing iprocess iwhere ia isection iof ithe iplasma
imembrane ienfolds isubstances ifrom ioutside ithe icell, iinvaginates iand iseparates ifrom
ithe iplasma imembrane iforming ia ivesicle ithat imoves iinside ithe icell. iIt ican ibe idivided
iin ito ifour icategories:
a. Clatherin-mediated iendocytosis
b. Caveolae-mediated iendocytosis
c. Macropinocystosis
d. Phagocytosis
22. Diffusion iis ithe ipassive imovement iof ia isolute ifrom ian iarea iof ihigher isolute
iconcentration ito ian iarea iof ilower isolute iconcentration.
23. Hydrostatic ipressure iis ithe imechanical iforce iof iwater ipushing iagainst icellular
imembranes.
24. Osmosis iis ithe imovement iof iwater iacross ia isemipermeable imembrane ifrom ia
iregion iof ilower isolute iconcentration ito ia iregion iof ihigher isolute iconcentration.
a. The iamount iof ihydrostatic ipressure irequired ito ioppose ithe iosmotic
imovement iof iwater iis icalled ithe iosmotic ipressure iof ithe isolution.
b. The ioverall iosmotic ieffect iof icolloids isuch ias iplasma iproteins iis icalled ithe
oncotic ipressure/colloid ipressure.
Chapter i2: iAltered iCellular iand iTissue iBiology
1. Injury ito icells iand itheir isurrounding ienvironment icalled ithe iextracellular imatrix
i(ECM) ileads ito itissue iand iorgan iinjury. iCellular iadaption iis ian ialteration ithat ienables
ithe icell ito imaintain ia isteady istate idespite ithe iadverse iconditions.
2. Atrophy iis ia idecrease iis icellular isize. iThe imechanisms iprobably iinclude idecreased
iprotein isynthesis, iincreased iprotein icatabolism ior iboth.
3. Hypertrophy iis ian iincrease iin ithe isize iof icells icaused iby iincreased iwork idemands
ior ihormonal istimulation.
a. This ican ieither ibe iphysiologic ior ipathologic.
, b. Amounts iof iprotein iin ithe iplasma imembrane, iER, imicrofilaments iand
imitochondria iare iincreased.
4. Hyperplasia iis ian iincrease iin ithe inumber iof icells icaused iby ian iincreased irate iof
icellular idivision.
a. Compensatory ihyperplasia ienables icertain iorgans ito iregenerate i(like ithe
iliver).
b. Hormonal ihyperplasia iis istimulated iby ihormones ito ireplace ilost itissue ior
isupport inew igrowth i(pregnancy).
c. Pathologic ihyperplasia iis ithe iabnormal iproliferation iof inormal icells iin
iresponse ito iexcessive ihormonal istimulation iof igrowth ifactors ion itarget icells.
5. Dysplasia i(atypical ihyperplasia) iis ian iabnormal ichange iin ithe isize, ishape iand
iorganization iof imature itissue icells.
6. Metaplasia iis ithe ireversible ireplacement iof ione imature icell itype iby ianother iless
imature icell itype.
a. Thought ito idevelop ifrom ia ireprogramming iof istem icells iexisting iin imost
iepithelia ior iof iundifferentiated imesenchyme icells iin iconnective itissue.
7. Injury ito icells iand ithe iECM ileads ito iinjury iof itissues iand iorgans, iultimately
idetermining ithe istructural ipatterns iof idisease. iCells imay irecover i(reversible) ior
imay idie i(irreversible).
a. Injury iis icaused iby ia ilack iof ioxygen, ifree iradicals, icaustic ior itoxic ichemicals,
iinfections iagents, iunintentional iand iintentional iinjury; iinflammatory iand
iimmune iresponses, igenetic ifacts, iinsufficient inutrients, ior iphysical itrauma
ifrom iother imeans.
b. Cell iinjury ican iby iacute ior ichronic iand iit ican ibe ireversible ior iirreversible. iIt
ican iinvolve inecrosis, iapoptosis, iautophagy, iaccumulation ior ipathologic
icalcification.
8. There iare ifour ibiochemical ithemes ithat iare iimportant ito icell iinjury:
a. Depletion iof iATP
b. Decreased ilevels iof ioxygen iand iincreased ilevels iof iocygen-derived ifree
iradicals
c. Increased iconcentration iof iintracellular icalcium iand iloss iof icalcium isteady
istate
d. Defects iin ithe imembrane ipermeability.
9. The iinitial iinsult iin ihypoxic iinjury iis iusually iischemia—the icessation iof iblood iflow
iinto ivessels ithat isupply ithe icell iwith ioxygen iand inutrients.
10. An iimportant imechanism iof imembrane idamage iis iinjury icaused iby ifree iradical
iincluding ioxidative istress. iFree iradicals iare idifficult ito icontrol iand iinitiate ichain
ireactions. iFree iradical ican icause:
a. Lipid iperoxidation ior ithe idestruction iof iunsaturated ifatty iacids
b. Alterations iof iproteins
c. Alterations iin iDNA
11. The iinitial iinsult iin ichemical iinjury iis idamage ior idestruction iof ithe iplasma
imembrane. iExamples iof ichemical iagents ithat icause icellular iinjury iinclude ilead,
icarbon imonoxide, iethanol, imercury iand istreet idrugs.
