UNIT6:CellMembraneTransport Name:_____________________EssentialIdea(s):Membranescontrolthecompositionofcellsbyactiveandpassivetransport

IBAssessmentStatements

1.1.U3 CellSurfacetovolumeisanimportantlimitationtocellsize.• Outlinetheactivitiesoccurringinthevolumeandatthesurfaceofthecell.• Calculatethesurfacearea,volumeandSA:Vratioofacube.• Explainthebenefitsandlimitationsofusingcubestomodelthesurfaceareaandvolumeofacell.• DescribetherelationshipbetweencellsizeandtheSA:Vratioofthecell.• ExplainwhycellsareoftenlimitedinsizebytheSA:Vratio.• ListthreeadaptationsofcellsthatmaximizetheSA:volumeratio.

1.4.U1 Particlesmoveacrossmembranesbysimplediffusion,facilitateddiffusion,osmosisandactivetransport.• Describesimplediffusion.• Explaintwoexamplesofsimplediffusionofmoleculesintoandoutofcells.• Outlinefactorsthatregulatetherateofdiffusion.• Describefacilitateddiffusion.• Describeoneexampleoffacilitateddiffusionthroughaproteinchannel.• Defineosmosis.• Predictthedirectionofwatermovementbasedupondifferencesinsoluteconcentration.• Compareactivetransportandpassivetransport.• Explainoneexampleofactivetransportofmoleculesintoandoutofcellsthroughproteinpumps

1.4.S1 Estimationofosmolarityintissuesbybathingsamplesinhypotonicandhypertonicsolutions.• Defineosmolarity,isotonic,hypotonicandhypertonic.• Calculatethepercentagechangebetweenmeasurementvalues.• Calculatethemeanvalueofadataset.• Calculatethestandarddeviationvalueofadataset.• Statethatthetermstandarddeviationisusedtosummarizethespreadofvaluesaroundthemean,and

that68%ofthevaluesfallwithinonestandarddeviationofthemean.• Explainhowthestandarddeviationisusefulforcomparingthemeansandthespreadofdatabetweentwo

ormoresamples.• Determinethecorrecttypeofgraphtorepresentexperimentalresults.• Statethaterrorbarsareagraphicalrepresentationofthevariabilityofdata.• Accuratelygraphmeanandstandarddeviationofdatasets.• Determineosmolarityofasamplegivenchangesinmasswhenplacedinsolutionsofvarioustonicities.

1.4.NOS Experimentaldesign-accuratequantitativemeasurementinosmosisexperimentsisessential.• Definequantitativeandqualitative.• Determinemeasurementuncertaintyofameasurementtool.• Explaintheneedforrepeatedmeasurements(multipletrials)inexperimentaldesign.• Explaintheneedtocontrolledvariablesinexperimentaldesign.

1.4.A2 Tissuesororganstobeusedinmedicalproceduresmustbebathedinasolutionwiththesameosmolarityasthecytoplasmtopreventosmosis.

• Explainwhathappenstocellswhenplacedinsolutionsofthesameosmolarity,higherosmolarityandlowerosmolarity.

• Outlinetheuseofnormalsalineinmedicalprocedures

1.4.U2 Thefluidityofmembranesallowsmaterialstobetakenintocellsbyendocytosisorreleasedbyexocytosis.• Describethefluidpropertiesofthecellmembraneandvesicles.• Explainvesicleformationviaendocytosis.• Outlinetwoexamplesofmaterialsbroughtintothecellviaendocytosis.• Explainreleaseofmaterialsfromcellsviaexocytosis.• Outlinetwoexamplesofmaterialsreleasedfromacellviaexocytosis

SURFACEAREA:VOLUME(…whycellsaresmall…)

SURFACEAREACellsurfaceareadictates…Themoresurfacearea,themore…VOLUMECellvolumedictates…Themorevolume,themore….

Somecellsincreasesurfaceareatovolumeratiobyhaving… sketchanddescribe

Asacellbecomestoolarge….

SIMPLEDIFFUSION

DIFFUSIONIS:PHOSPHOLIPIDBILAYERMUSTBE:EXAMPLES:

DiffusionofCO2andO2intoandoutoflungalveoli

DiffusionofCO2andO2intoandoutofeyecorneacells

CAPTION:

Ratesofdiffusiondependon:

FACILITATEDDIFFUSION

FACILTATEDDIFFUSIONIS:PHOSPHOLIPIDBILAYERMUSTBE…EXAMPLE:

CAPTION:

OSMOSIS

OSMOSISIS:OSMOSISDEPENDSON…

HYPOTONIC

ISOTONIC HYPERTONIC

WhathappenstocellsplacedinHYPOTOMICSOLUTION

WhathappenstocellsplacedinISOTONICSOLUTION

WhathappenstocellsplacedinHYPERTONICSOLUTION

CAPTION:

ACTIVETRANSPORT

ACTIVETRANSPORTIS:PROTEINPUMPS:EXAMPLES:

SodiumPotassiumPumpinNeurons

ProtonPumpinCellularRespirationandPhotosynthesis

CAPTION: