Download Spectacular Cells and Marvelous Membranes : Teacher Overview

SpectacularCellsandMarvelousMembranes:TeacherOverview
SC.6.L.14.4 Compare and contrast the structure and function of major organelles of plant and
animal cells, including cell wall, cell membrane, nucleus, cytoplasm, chloroplasts, mitochondria,
and vacuoles.
SC.912.L.14.1 Describe the scientific theory of cells (cell theory) and relate the history of its
discovery to the process of science.
SC.912.L.14.2 Relate structure to function for the components of plant and animal cells. Explain
the role of cell membranes as a highly selective barrier (passive and active transport).
SC.912.L.14.3 Compare and contrast the general structures of plant and animal cells. Compare
and contrast the general structures of prokaryotic and eukaryotic cells.
LearningOutcomes:
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Understandthefunctionofthecellmembraneasaselectivelypermeablebarrier
Followthemovementofwateracrossamembraneduetoosmosis
Predictthedirectionofmovementofsolutesacrossamembraneduetorelative
concentrationdifferences
Identifycommonstructuresofcells
Recognizethatcellstakemanyshapesbasedon theirfunction
GettingStarted:
 Reviewthebasicstointroducewhatacellisandintroducetheideathatcells
requiretheabilitytotransport moleculesacrossthemembrane.
 Demonstratetheconceptofaconcentrationgradientandhowmoleculestendto
movefromhigherconcentrationstolowerconcentration(ex.Havestudentsstand in
atightgroupandletthemobservetheirnaturaltendencytowanttomoveaway
fromeachother).
 Explainthedifferencebetweendiffusionandosmosisandintroducetheterms
isotonic,hypertonic,andhypotonic.
DiffusionandOsmosisExperiment:TeacherNotes
Materials:
 Clearplasticcupsorbeakers
 Graduatedcylinder
 Iodine
 Packingpeanutsor10%starchsoln.
Procedure:
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Plasticsandwichbags(sealable)
Scale(g)
Sequinsorglitter
Water
1. Measure200mLofwaterandplaceincup(orbeaker).
2. Add25dropsofiodinetothecupandmixgently.
3. Inyourbaggie,combine:
 15mLwarmwater
 1packingpeanut
 Pinchofsequins(orglitter)
4. Sealthebaggiecompletelybutleavealittleairinthebag.
5. Weighthebaggieandrecordtheinitialweight.
6. Placethebaggieinthecupcontainingiodineandmakeyourinitialobservations(see
studenthandout).
7. Wait30minutes.
8. Checkthebaggieandsolutioninthecupforchangesinappearanceandmakeyourfinal
observations.
9. Removethebaggieandpatdrywithpapertowelstoremoveexcesswater.
10. Weighthebaggieandrecordthefinalweight.
StudentHandout
ExploringMembraneTransport
Usingeverydayitems,youwillcreatecellandcytoplasmtoexplorehowmolecules move
acrossamembrane.
Procedure:
Makingthecellenvironment:
1. Measure200mLofwaterusingthegraduatedcylinderandplaceitinthecup
provided.
2. Add25dropsofiodinetothecupandmixgently.
Makingthecellandcytoplasm:
3. Inasandwichbaggie,combine:
 15mLwarmwater
 1packingpeanut(madeofstarch)
 Pinchofsequins(representsproteins)
4. Sealthebaggiecompletelybutleavealittleairinthebag.
Nowthatyou’vemadeyourcellitistimetoconductyourexperiment.
5. Weighthecell(baggie)andrecordtheinitialweightinthedatatable(nextpage)
6. Placethebaggieinthecupcontainingiodineandmakeyourinitialobservationsin
thedatatable(nextpage).
7. Wait30minutes.
8. Checkthebaggieandsolutioninthecupforchangesinappearanceandmakeyour
finalobservationsinthedatatable.
9. Removethebaggieandpatdrywithpapertowelstoremoveexcesswater.
10. Weighthebaggieandrecordthefinalweightinthedatatable.
StudentReportingSheet
Usethetermsbelowtolabelthediagramandshowwhereeachitemwaslocatedwhenyou
initiallysetupyourexperiment.
Iodine
Water
Starch
Sequins
Observations
Initial
Final
CellWeight(g)
Colorofexternalfluid Colorofcytoplasm
Locationofproteins
SummaryQuestions:
1. Whatpartofacelldoesthebaggierepresent?
2. Basedonthedifferenceincellweight,whichdirectiondidthe watermoveinthis
experiment?(Circleone)
Intothecell Outofthecell
Nomovement
3. Comparethecolorofthecellenvironmentandcytoplasmatthebeginningof the
experimenttothecolorattheendoftheexperiment.Whatdoesthiscolorchange
tellyouaboutthemovementofstarchand/oriodine?
StudentReportingSheet(KEY)
Usethetermsbelowtolabelthediagramandshowwhereeachitemwaslocatedwhenyou
initiallysetupyourexperiment.
Iodine
Water
Starch
Sequins
Observations
Initial
Final
CellWeight(g)
(willvarybutwillbelower
(willvarybutwillbehigher
thanfinal)
thaninitial)
Colorofexternalfluid Lightyellow
Lightyellowtoclear
Colorofcytoplasm
Clear
Purple
Locationofproteins
Insidebag/cell
Insidebag/cell
SummaryQuestions:
1. Whatpartofacelldoesthebaggierepresent?Cellmembrane
2. Basedonthedifferenceincellweight,whichdirectiondidthe watermoveinthis
experiment?(Circleone)
Intothecell Outofthecell
Nomovement
3. Comparethecolorofthecellenvironmentandcytoplasmatthebeginningof the
experimenttothecolorattheendoftheexperiment.Whatdoesthiscolorchange
tellyouaboutthemovementofstarchand/oriodine?
Theiodinemovedintothebagandturnedpurplewhenincontact withstarch.
Starchwasnotabletomove outofthecell(toolarge).
CellMicroscopy:TeacherNotes
Studentsrotatethroughaseriesofstationstoobservevarious cellsamplesatthe
microscopiclevel.Youcanchangeupthespecimensyoushow,butIsuggestusingavariety
ofsamples(eukaryotic,prokaryotic,animal,plant,etc.)todemonstratethemany
differencesincellstructureswhilehighlightingthecommonalitiespresentinallcells.
Materials:
 Compoundmicroscopes
 Preparedslides(seeadditionalhandoutonhowtoprepareslidesinadvance)
 Copiesofstudenthandout
 Printedlargeimageofeachorganism (optional)
Settingup:
 Eachstation shouldbepresetwithamicroscopeandasinglesampleslidealready
positionedandfocused forthestudents.
 Youmaywanttoincludealargeprintedimageoftheorganismbeingimagedateach
stationforthestudentstoreferencesotheyknowwhattheyshouldbeseeingifthey
arehavingdifficultywiththemicroscope.
 Thelightshouldbeturnedoffuntilthestudentsarereadytoviewtoprevent
specimensfromdryingoutoroverheating.
Procedure:
1. Studentswillstartinsmallgroups(3‐5studentspergroup)spreadacrossthestations.
2. Eachstudentshouldgetachancetoviewthespecimenthroughthemicroscope.
3. Studentsaretodrawaquickdescriptionofwhattheyseeontheprovidedworksheet.
Studentsshouldalsoidentifycharacteristicsofeachspecimen(shape,cellularity,color)
ontheworksheetaswellasanyspecialobservations(notes)aboutwhattheysee.
4. Groupswillhaveapproximately10minutesateachstation(mayvary dependingon
groupsize,numberofstations,andallottedtime).
Eachgroupwillthenrotatetothenextstation,clockwise.
5. Thisprocesswillrepeatuntilallgroupshavecompletedeachstation.
6. Groupswillcometogetherattheirtablesanddiscusstheirfindings.
Oneachtablewillbeasetofunlabeledimages(oneofeachspecimenviewed)andaset
ofspecimennameswithorganismcharacteristicslisted.
Groupswillworktogethertoidentifythenameofeachspecimenbymatchingthe image
withthenameusingtheirobservationnotes.
7. Thecorrectanswerswillberevealedattheendofthesessionanddifferencesand
commonfeaturesofcellswillbediscussed.
CellMicroscopy:StudentHandout
CellMicroscopy
Nowletsobserverealcellsupcloseandpersonal.Asyoutravelthrough3stations,youwill
get a chance to observe 3 different specimens at the cellular level. Draw aquick picture of
what you see and circle the words that describe that cell. Be sure to write your
observationsinthecorrectareaforeachstation.
NameThatCell!
Onyourtablesyou willfindcards withorganismnamesanddefiningcharacteristicsofthat
organismaswellasrepresentativeimagesofeachspecimen.
Usethesecardsandyournotestodeterminethenameofeachspecimenyouobserved.
Workwithyourgroupmembersand compareyournotestomakethe propermatches.
IsthatyourFINALanswer?
Nostoc
Elodea
Paramecium
Station____________
Station____________
Station____________
AdditionalTeacherResources
ExampleSpecimenImageandCorrespondingNameandCharacteristicsCard
Station1Specimen
Name:Nostoc
Celltype:cyanobacteria
Commoncharacteristics:
Smallcircularcellsthatgrowinlongcolonies
Containchlorophyllpigments
ShrinkyDinkInstructions
Instructions:
Inclass…
1. Drawyourcelldesignontheshrinkdinkfilm.
2. Decoratewiththemarkersprovided.
3. Cutoutyourdesign.(Besuretoleavetheholetoattachthekeyringlater)
4. Takeyourdesignhomeforbaking.
IMPORTANT!ASKANADULTTOHELPWITHBAKING.
Athome…
5. Pre‐heat oven between 300‐350°F. (Note: test a scrap piece of shrinky dink film to
determinebestbakingtemperature)
6. Placethedesignonacookiesheetlinedwithmediumweightcardboardorparchment
paper.(Note:DONOTbackonbaremetaloranystoneware)
7. Heatforapproximately2‐3minutesuntilcompletelyflatandshrinkinghasstopped.
Usecautionwhenhandling;designswillbeHOT!