OCR GCSE Combined Science A J250 Specification...as a starng point for lesson planning. Praccal suggesons (See topic CS7) Learning outcomes To include Maths (See appendix 5e) Working

Syllabus Snapshot

GCSE Science - Gateway

Combined Science A

Exam Board: OCR

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GCSE (9–1) in Combined Science A (Gateway Science)

LearnersareenteredforeitherFoundationTier(Papers1,2,3,4,5and6)orHigherTier(Papers7,8,9,10,11and12).ThisqualificationisworthtwoGCSEs.

Content Overview Assessment Overview

Foundation Tier,grades5–5to1–1

• TopicB1:Celllevelsystems• TopicB2:Scalingup• TopicB3:Organismlevelsystems• TopicCS7:Practicalskills(PAGsB1-B5)

Paper1(Biology)J250/01

1hour10minutes60markwrittenpaper

16.7%oftotalGCSE

• TopicB4:Communitylevelsystems• TopicB5:Interactionbetweensystems• TopicB6:Globalchallenges• TopicCS7:Practicalskills(PAGsB1-B5)WithassumedknowledgeofB1–B3

Paper2(Biology)J250/02


16.7%oftotalGCSE

• TopicC1:Particles• TopicC2:Elements,compoundsandmixtures• TopicC3:Chemicalreactions• TopicCS7:Practicalskills(PAGsC1-C5)

Paper3(Chemistry)J250/03


16.7%oftotalGCSE

• TopicC4:Predictingandidentifyingreactionsandproducts

• TopicC5:Monitoringandcontrollingchemicalreactions

• TopicC6:Globalchallenges• TopicCS7:Practicalskills(PAGsC1-C5)WithassumedknowledgeofC1–C3

Paper4(Chemistry)J250/04


16.7%oftotalGCSE

• TopicP1:Matter• TopicP2:Forces• TopicP3:Electricityandmagnetism• TopicCS7:Practicalskills(PAGsP1-P6)

Paper5(Physics)J250/05


16.7%oftotalGCSE

• TopicP4:Wavesandradioactivity• TopicP5:Energy• TopicP6:Globalchallenges• TopicCS7:Practicalskills(PAGsP1-P6)WithassumedknowledgeofP1–P3.

Paper6(Physics)J250/06


16.7%oftotalGCSE

J250/02,J250/04andJ250/06includesynopticassessment.

2a. OCR’s GCSE (9–1) in Combined Science A (Gateway Science) (J250)

2 The specification overview

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Content Overview Assessment Overview

Higher Tier,grades9–9to4–4

• TopicB1:Celllevelsystems• TopicB2:Scalingup• TopicB3:Organismlevelsystems• TopicCS7:Practicalskills(PAGsB1-B5)

Paper7(Biology)

J250/07


16.7%oftotalGCSE

• TopicB4:Communitylevelsystems• TopicB5:Interactionbetweensystems• TopicB6:Globalchallenges• TopicCS7:Practicalskills(PAGsB1-B5)

WithassumedknowledgeofB1–B3

Paper8(Biology)

J250/08


16.7%oftotalGCSE

• TopicC1:Particles• TopicC2:Elements,compoundsandmixtures• TopicC3:Chemicalreactions• TopicCS7:Practicalskills(PAGsC1-C5)

Paper9(Chemistry)

J250/09


16.7%oftotalGCSE

• TopicC4:Predictingandidentifyingreactionsandproducts

• TopicC5:Monitoringandcontrollingchemicalreactions

• TopicC6:Globalchallenges• TopicCS7:Practicalskills(PAGsC1-C5)

WithassumedknowledgeofC1–C3

Paper10(Chemistry)

J250/10


16.7%oftotalGCSE

• TopicP1:Matter• TopicP2:Forces• TopicP3:Electricityandmagnetism• TopicCS7:Practicalskill(PAGsP1-P6)

Paper11(Physics)

J250/11


16.7%oftotalGCSE

• TopicP4:Wavesandradioactivity• TopicP5:Energy• TopicP6:Globalchallenges• TopicCS7:Practicalskills(PAGsP1-P6)

WithassumedknowledgeofP1–P3

Paper12(Physics)

J250/12


16.7%oftotalGCSE

J250/08,J250/10andJ250/12includesynopticassessment.

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GCSE (9–1) in Combined Science A (Gatew

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2b. Content of GCSE (9–1) in Combined Science A (Gateway Science) (J250)

TheGCSE(9–1)inCombinedScienceA(GatewayScience)specificationcontentisspecifiedinsection2cItisdividedinto18teachingtopicsB1-B6,C1-C6&P1-P6andapracticalactivityskillstopicCS7.

LearningatGCSE(9–1)inCombinedScienceA(GatewayScience)isdescribedinthetablesthatfollow:

Overview of the content layout

Topic B/C/P1: Topic title

B1.1 sub-topic

SummaryAshortoverviewofthesub-topicthatwillbeassessedintheexaminations.

Underlying knowledge and understandingUnderlyingknowledgeandunderstandinglearnersshouldbefamiliarwithlinkedtothesub-topic

Common misconceptionsCommonmisconceptionsstudentsoftenhaveassociatedwiththistopic

TieringAbriefsummaryofthetieringofthesub-topic

Reference Mathematical learning outcomes Mathematical skills(Seeappendix5f)

OCRsmathematicsreferencecode

Thiscolumndefinestheareasofmathematicsthatwillneedtobetaughtspecificallywithinthecontextofthissub-topic.Questionsintheexaminationwillassesstheselearningoutcomeswithinthecontextofthetopic.

MathematicalskillcodeasindicatedinAppendix5e

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Topic contentOpportunities to cover:

Itemsthatarecontainedwithinthesecolumnsareintendedasastartingpointforlessonplanning. Practical suggestions

(SeetopicCS7)

Learning outcomes To include Maths(Seeappendix5e)

Working scientifically(Seeappendix5d)

Spec.referencenumber

Columnspecifiesthesubjectcontentthatwillbeassessedintheexaminations.

Thiscolumnisincludedtoprovidefurther/specificadviceondeliveryofthelearningoutcome.

Mathematicalskillswillbeassessedthroughouttheexamination.Thiscolumnhighlightsthemathematicalskillsthatcouldbetaughtalongsidethetopiccontent.

Workingscientificallywillbeassessedthroughouttheexamination.Thiscolumnhighlightstheworkingscientificallyskillsthatcouldbetaughtalongsidethetopiccontent.

ThecompulsorypracticalskillscoveredbythePracticalActivityGroupsorPAGsareindicatedinthetablesinTopicCS7.ActivitiesinthiscolumncanbeusedtosupplementthePAGsusingtopicappropriateexperiments

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Biologyisthescienceoflivingorganisms(includinganimals,plants,fungiandmicroorganisms)andtheirinteractionswitheachotherandtheenvironment.Thestudyofbiologyinvolvescollectingandinterpretinginformationaboutthenaturalworldtoidentifypatternsandrelatepossiblecauseandeffect.Biologicalinformationisusedtohelphumansimprovetheirownlivesandstrivetocreateasustainableworldforfuturegenerations.

Learnersshouldbehelpedtounderstandhow,throughtheideasofbiology,thecomplexanddiversephenomenaofthenaturalworldcanbedescribedintermsofasmallnumberofkeyideaswhichareofuniversalapplication,andwhichcanbeillustratedintheseparatetopicssetoutbelow.Theseideasinclude:

• lifeprocessesdependonmoleculeswhosestructureisrelatedtotheirfunction

• thefundamentalunitsoflivingorganismsarecells,whichmaybepartofhighlyadaptedstructuresincludingtissues,organsandorgansystems,enablinglivingprocessestobeperformedeffectively

• livingorganismsmayformpopulationsofsinglespecies,communitiesofmanyspeciesand

ecosystems,interactingwitheachother,withtheenvironmentandwithhumansinmanydifferentways

• livingorganismsareinterdependentandshowadaptationstotheirenvironment

• lifeonEarthisdependentonphotosynthesisinwhichgreenplantsandalgaetraplightfromtheSuntofixcarbondioxideandcombineitwithhydrogenfromwatertomakeorganiccompoundsandoxygen

• organiccompoundsareusedasfuelsincellularrespirationtoallowtheotherchemicalreactionsnecessaryforlife

• thechemicalsinecosystemsarecontinuallycyclingthroughthenaturalworld

• thecharacteristicsofalivingorganismareinfluencedbyitsgenomeanditsinteractionwiththeenvironment

• evolutionoccursbyaprocessofnaturalselectionandaccountsbothforbiodiversityandhoworganismsareallrelatedtovaryingdegrees.

Biology key ideas

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Chemistryisthescienceofthecomposition,structure,propertiesandreactionsofmatter,understoodintermsofatoms,atomicparticlesandthewaytheyarearrangedandlinktogether.Itisconcernedwiththesynthesis,formulation,analysisandcharacteristicpropertiesofsubstancesandmaterialsofallkinds.

Learnersshouldbehelpedtoappreciatetheachievementsofchemistryinshowinghowthecomplexanddiversephenomenaofboththenaturalandman-madeworldscanbedescribedintermsofasmallnumberofkeyideaswhichareofuniversalapplication,andwhichcanbeillustratedintheseparatetopicssetoutbelow.Theseideasinclude:

• matteriscomposedoftinyparticlescalledatomsandthereareabout100differentnaturallyoccurringtypesofatomscalledelements

• elementsshowperiodicrelationshipsintheirchemicalandphysicalpropertiestheseperiodic

propertiescanbeexplainedintermsoftheatomicstructureoftheelements

• atomsbondbyeithertransferringelectronsfromoneatomtoanotherorbysharingelectrons

• theshapesofmolecules(groupsofatomsbondedtogether)andthewaygiantstructuresarearrangedisofgreatimportanceintermsofthewaytheybehave

• therearebarrierstoreactionsoreactionsoccuratdifferentrates

• chemicalreactionstakeplaceinonlythreedifferentways:• protontransfer• electrontransfer• electronsharing

• energyisconservedinchemicalreactionssocanthereforebeneithercreatedordestroyed.

Chemistry key ideas

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Physicsisthescienceofthefundamentalconceptsoffield,force,radiationandparticlestructures,whichareinter-linkedtoformunifiedmodelsofthebehaviourofthematerialuniverse.Fromsuchmodels,awiderangeofideas,fromthebroadestissueofthedevelopmentoftheuniverseovertimetothenumerousanddetailedwaysinwhichnewtechnologiesmaybeinvented,haveemerged.Thesehaveenrichedbothourbasicunderstandingof,andourmanyadaptationsto,ourmaterialenvironment.

Studentsshouldbehelpedtounderstandhow,throughtheideasofphysics,thecomplexanddiversephenomenaofthenaturalworldcanbedescribedintermsofasmallnumberofkeyideaswhichareofuniversalapplicationandwhichcanbeillustratedintheseparatetopicssetoutbelow.Theseideasinclude:

• theuseofmodels,asintheparticlemodelofmatterorthewavemodelsoflightandofsound

• theconceptofcauseandeffectinexplainingsuchlinksasthosebetweenforceandacceleration,orbetweenchangesinatomicnucleiandradioactiveemissions

• thephenomenaof‘actionatadistance’andtherelatedconceptofthefieldasthekeytoanalysingelectrical,magneticandgravitationaleffects

• thatdifferences,forexamplebetweenpressuresortemperaturesorelectricalpotentials,arethedriversofchange

• thatproportionality,forexamplebetweenweightandmassofanobjectorbetweenforceandextensioninaspring,isanimportantaspectofmanymodelsinscience

• thatphysicallawsandmodelsareexpressedinmathematicalform.

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Summary of content for GCSE (9–1) in Combined Science A (Gateway Science) – Biology

Topic B1: Cell level systems Topic B2: Scaling up Topic B3: Organism level systems

B1.1 CellstructuresB1.2 Whathappensincells(andwhatdocells

need)?B1.3 RespirationB1.4 Photosynthesis

B2.1 SupplyingthecellB2.2 Thechallengesofsize

B3.1 Coordinationandcontrol–thenervoussystemB3.2 Coordinationandcontrol–theendocrine

systemB3.3 Maintaininginternalenvironments

Topic B4: Community level systems Topic B5: Genes, inheritance and selection Topic B6: Global challenges

B4.1 Ecosystems B5.1 InheritanceB5.2 Naturalselectionandevolution

B6.1 MonitoringandmaintainingtheenvironmentB6.2 FeedingthehumanraceB6.3 Monitoringandmaintaininghealth

CS7isapractical-basedtopicwhichprovideslearnerswiththenecessaryskillstoundertakethe15%practicalcontentintheexaminations.

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Summary of content for GCSE (9–1) in Combined Science A (Gateway Science) – Chemistry

Topic C1: Particles Topic C2: Elements, compounds and mixtures Topic C3: Chemical reactions

C1.1 TheparticlemodelC1.2 Atomicstructure

C2.1 PurityandseparatingmixturesC2.2 BondingC2.3 Propertiesofmaterials

C3.1 IntroducingchemicalreactionsC3.2 EnergeticsC3.3 TypesofchemicalreactionsC3.4 Electrolysis

Topic C4: Predicting and identifying reactions and products

Topic C5: Monitoring and controlling chemical reactions Topic C6: Global challenges

C4.1 Predictingchemicalreactions C5.1 ControllingreactionsC5.2 Equilibria

C6.1 ImprovingprocessesandproductsC6.2 InterpretingandinteractingwithEarthsystems


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Summary of content for GCSE (9–1) in Combined Science A (Gateway Science) – Physics

Topic P1: Matter Topic P2: Forces Topic P3: Electricity and magnetism

P1.1 TheparticlemodelP1.2 Changesofstate

P2.1 MotionP2.2 Newton’slawsP2.3 Forcesinaction

P3.1 StaticandChargeP3.2 SimplecircuitsP3.3 Magnetsandmagneticfields

Topic P4: Waves and radioactivity Topic P5: Energy Topic P6: Global challenges

P4.1 WavebehaviourP4.2 TheelectromagneticspectrumP4.3 Radioactivity

P5.1 WorkdoneP5.2 Powerandefficiency

P6.1 PhysicsonthemoveP6.2 PoweringEarth


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2c. Content of topics B1 to B6, C1 to C6 and P1 to P6

Topic B1: Cell level systems

B1.1 Cell structures

SummaryCellsarethefundamentalunitsoflivingorganisms.Cellscontainmanysub-cellularstructuresthatareessentialforthefunctioningofthecellasawhole.Microscopyisusedtoexaminecellsandsub-cellularstructures.

Underlying knowledge and understandingLearnersshouldbefamiliarwithcellsasthefundamentalunitoflivingorganisms,andwiththeuseoflightmicroscopestoviewcells.Theyshouldalsobefamiliarwithsomesub-cellularstructures,andthesimilaritiesanddifferencesbetweenplantandanimalcells.

Common misconceptionsLearnerscommonlyhavedifficultyunderstandingtheconceptofacellasa3Dstructure,sothisshouldbeaddressedduringtheteachingofthistopic.

TieringStatementsshowninboldtypewillonlybetestedintheHigherTierpapers.AllotherstatementswillbeassessedinbothFoundationandHigherTierpapers.

Reference Mathematical learning outcomes Maths skills

BM1.1i demonstrateanunderstandingofnumber,sizeandscaleandthequantitativerelationshipbetweenunits M2aandM2h

BM1.1ii useestimationsandexplainwhentheyshouldbeused M1d

BM1.1iii calculate with numbers written in standard form M1b

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Topic content Opportunities to cover:

Practical suggestionsLearning outcomes To include Maths Working scientifically

B1.1a describehowlightmicroscopesandstainingcanbeusedtoviewcells

lenses,stage,lamp,useofslidesandcoverslips,andtheuseofstainstoviewcolourlessspecimensortohighlightdifferentstructures/tissuesandcalculationofthemagnificationused

M1d,M2a,M2h

WS1.2c,WS1.4c,WS1.4d,WS1.4e,WS2a,WS2b,WS2c,WS2d

Investigationofarangeofcellsusingpictures,lightmicrographsanddiagrams.Measurethesizeandmagnificationofthecells.(PAGB1)

Preparationofcheekcellslides.(PAGB1,PAGB5)

Preparationofonionepidermiscellsslides.(PAGB1,PAGB4)

Useoflightmicroscopestoviewplantandanimalcells.(PAGB1,PAGB4,PAGB5)

B1.1b explainhowthemainsub-cellularstructuresofeukaryoticcells(plantsandanimals)andprokaryoticcellsarerelatedtotheirfunctions

nucleus,geneticmaterial,chromosomes,plasmids,mitochondria(containenzymesforcellularrespiration),chloroplasts(containchlorophyll)andcellmembranes(containreceptormolecules,providesaselectivebarriertomolecules)

WS1.4a,WS2a,WS2b,WS2c,WS2d

Demonstratethestructureofplantandanimalcellsbyconstructing3Dmodels.

InvestigationofcytoplasmicstreaminginElodeaspp.(PAGB1,PAGB4)

B1.1c explainhowelectronmicroscopyhasincreasedourunderstandingofsub-cellularstructures

toincludeincreasedresolutioninatransmissionelectronmicroscope

M1b WS1.1a,WS1.4c,WS1.4d

Comparisonofarangeofcellsusingpicturesfromlightandelectronmicrographs.

Comparisonofthestructuresvisibleonlightandelectronmicrographs.

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B1.2 What happens in cells (and what do cells need)?

SummaryLifeprocessesdependonbiologicalmoleculeswhosestructureisrelatedtotheirfunction.Insideeverycellisgeneticmaterialandthisisusedasacodetomakeproteins.Enzymesareimportantproteinsinbiology.

Underlying knowledge and understandingLearnersshouldhaveasimpleunderstandingofthedoublehelixmodelofDNA.Learnersshouldbefamiliarwiththeideaofenzymesasbiologicalcatalysts.

Common misconceptionsLearnerscommonlyholdthemisconceptionthatDNAismadeofproteinorsugar.Learnersalsothinkthatallenzymeshaveanoptimumtemperatureof37°C(humanbodytemperature).Therangeofoptimumtemperaturesofenzymesshouldbeintroducedthroughtheteachingofthistopicandfurtheraddressedwhenconsideringhomeostaticmechanismsforcontrollingtemperature.



BM1.2i carryoutratecalculationsforchemicalreactions M1aandM1c



DNA and protein synthesis

B1.2a describeDNAasapolymer WS1.4a DemonstrateofthestructureofDNAbyconstructing3Dmodels.

B1.2b describeDNAasbeingmadeupoftwostrandsformingadoublehelix

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Learning outcomes To include Maths Working scientifically Practical suggestions

B1.2c describeexperimentsthatcanbeusedtoinvestigateenzymaticreactions

M1a,M1c,M2g

WS1.1h,WS1.2b,WS1.2c,WS1.2e,WS1.3a,WS1.3b,WS1.3c,WS1.3d,WS1.3e,WS1.3f,WS1.3g,WS2a,WS2b,WS2c,WS2d

Investigationsofenzymeactivity,includingnumericalanalysisofdataandgraphicalrepresentationofresults.(PAGB3)

B1.2d explainthemechanismofenzymeaction

theroleofenzymesinmetabolism,theroleoftheactivesite,enzymespecificity(lockandkeyhypothesis)andfactorsaffectingtherateofenzymecontrolledreactions(pH,temperature,substrateandenzymeconcentration)

M1a,M1c,M3d,M4b

WS2a,WS2b,WS2c,WS2d

Demonstrationoftheeffectofamylaseonababyricepaste.(PAGB3)

Investigationofenzymecontrolledreactions.(PAGB3)

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B1.3 Respiration

SummaryMetabolicprocessessuchasrespirationarecontrolledbyenzymes.Organiccompoundsareusedasfuelsincellularrespirationtoallowtheotherchemicalreactionsnecessaryforlife.

Underlying knowledge and understandingLearnersshouldhavesomeunderpinningknowledgeofrespiration.Thisshouldincludethatrespirationinvolvesthebreakdownoforganicmoleculestoenablealltheotherchemicalprocessesnecessaryforlife.Learnersshouldbeabletorecallthewordequationforrespiration.

Common misconceptionsLearnerscommonlyholdthemisconceptionthatventilationisrespiration.Theycanalsogetconfusedbetweenthetermsbreakupandbreakdown.




B1.3a describecellularrespirationasauniversalchemicalprocess,continuouslyoccurringinalllivingcellsthatsupplyATP

WS1.2a

B1.3b describecellularrespirationasanexothermicreaction

WS1.2b Demonstrationofanexothermicreaction(e.g.heatpack).

B1.3c comparetheprocessesofaerobicandanaerobicrespiration

inplants/fungiandanimalsthedifferentconditions,substrates,productsandrelativeyieldsofATP

WS2a,WS2b,WS2c,WS2d

Researchintowhetherplantsrespire.(PAGB3,PAGB4)

Investigationoffermentationinfungi.(PAGB3)

Investigationofrespirationinyeastusingalginatebeadstoimmobilizethefungus.(PAGB3)

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B1.3d explaintheimportanceofsugarsinthesynthesisandbreakdownofcarbohydrates

toincludeuseofthetermsmonomerandpolymer

Demonstrationofthesynthesisandbreakdownofbiologicalmolecules(e.g.usingLegobricks).TestingofbiologicalmoleculesPAGB2

B1.3e explaintheimportanceofaminoacidsinthesynthesisandbreakdownofproteins

toincludeuseofthetermsmonomerandpolymer

TestingofbiologicalmoleculesPAGB2

B1.3f explaintheimportanceoffattyacidsandglycerolinthesynthesisandbreakdownoflipids

TestingofbiologicalmoleculesPAGB2

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B1.4 Photosynthesis

SummaryLifeprocessesdependonphotosynthesis.GreenplantsandalgaetraplightfromtheSuntofixcarbondioxidewithhydrogenfromwatermakingorganiccompounds.

Underlying knowledge and understandingLearnersshouldalsohavesomeunderpinningknowledgeofphotosynthesis.Theyshouldhaveanunderstandingthatplantsmakecarbohydratesintheirleavesbyphotosynthesis,andbeabletorecallthewordequationforphotosynthesis.

Common misconceptionsLearnersoftenthinkthatplantsdonotrespire.



BM1.4i understandandusesimplecompoundmeasuressuchastherateofareaction M1aandM1c

BM1.4ii translateinformationbetweengraphicalandnumericalform M4a

BM1.4iii plotanddrawgraphs,selectingappropriatescalesandaxes M4aandM4c

BM1.4iv extractandinterpretinformationfromcharts,graphsandtables M2candM4a

BM1.4v Understand and use inverse proportion – the inverse square law and light intensity in the context of factors affecting photosynthesis

M1c

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B1.4a describephotosyntheticorganismsasthemainproducersoffoodandthereforebiomassforlifeonEarth

Useofconceptcartoonstostartdiscussionsaboutphotosynthesis.

B1.4b describetheprocessofphotosynthesis

reactantsandproducts,two-stageprocess,locationofthereaction(inthechloroplasts)

WS2a,WS2b,WS2c,WS2d

Investigationofphotosynthesise.g.thePriestleyexperimentusingCabomba tocollectoxygenortheIngenhouszexperimenttoshowmassgain.(PAGB4)

B1.4c describephotosynthesisasanendothermicreaction

WS1.3b,WS1.3c,WS1.3e

Demonstrateanendothermicreaction(e.g.icepack).

B1.4d describeexperimentstoinvestigatephotosynthesis

WS2a,WS2b,WS2c,WS2d

Experimentstoshowtheconsequencesoflightexclusiononphotosynthesisingplants(e.g.testinggeraniumsforstarch).(PAGB4)

B1.4e explaintheeffectoftemperature,lightintensityandcarbondioxideconcentrationontherateofphotosynthesis

M1a,M1c,M2c,M4a,M4c,M1c

WS2a,WS2b,WS2c,WS2d

Investigationofphotosynthesisinalgaeusingalginatebeadstoimmobilizethealgae.(PAGB4)

B1.4f explain the interaction of these factors in limiting the rate of photosynthesis

M1a,M1cM2c,M4a,M1c

WS1.2b,WS1.2c,WS1.2eWS1.3a,WS1.3b,WS1.3c,WS1.3d,WS1.3f,WS1.3g,WS1.4e,WS2c,WS2d

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Topic B2: Scaling up

B2.1 Supplying the cell

SummaryCellstransportmanysubstancesacrosstheirmembranesbydiffusion,osmosisandactivetransport.Stemcellsarefoundinbothplantsandanimals.Thesestemcellscandivide,differentiateandbecomespecialisedtoformtissues,organsandorgansystems.

Underlying knowledge and understandingLearnersshouldbefamiliarwiththeroleofdiffusioninthemovementofmaterialsinandbetweencells.

Common misconceptionsLearnerscommonlyshowsomeconfusionregardingsurfaceareatovolumeratio,particularlyhowlargeranimalshaveasmallersurfaceareatovolumeratio.Theyalsoshowsomeconfusionastostemcells:wheretheyarefoundandtheirroles.Careshouldbetakentogivecleardefinitionswhencoveringthiscontent.



BM2.1i usepercentilesandcalculatepercentagegainandlossofmass M1c



B2.1a explainhowsubstancesaretransportedintoandoutofcellsthroughdiffusion,osmosisandactivetransport

examplesofsubstancesmoved,directionofmovement,concentrationgradientsanduseofthetermwaterpotential(nomathematicaluseofwaterpotentialrequired)

M1c,M1d WS2a,WS2b,WS2c,WS2d

Observationofosmosisinplantcellsusingalightmicroscope.

Demonstrationof‘creamingyeast’toshowosmosis.(PAGB1,PAGB5)

Investigationofchangesinmassofvegetablechipswhenplacedinsucrose/saltsolutionsofvaryingconcentrations.(PAGB4)

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B2.1b describetheprocessofmitosisingrowth,includingthecellcycle

thestagesofthecellcycleasDNAreplication,movementofchromosomes,followedbythegrowthofthecell

WS2a,WS2b,WS2c,WS2d

Modellingofmitosisusingeverydayobjectse.g.shoes,socksetc.

Observationofmitosisinstainedroottipcells.(PAGB1,PAGB4)

B2.1c explaintheimportanceofcelldifferentiation

theproductionofspecialisedcellsallowingorganismstobecomemoreefficientandexamplesofspecialisedcells

WS2a,WS2b,WS2c,WS2d

Examinationofarangeofspecialisedcellsusingalightmicroscope.(PAGB1,PAGB4,PAGB5)

B2.1d recallthatstemcellsarepresentinembryonicandadultanimalsandmeristemsinplants

Demonstrationofcloningusingcauliflower.(PAGB4)

B2.1e describethefunctionsofstemcells divisiontoproducearangeofdifferentcelltypesfordevelopment,growthandrepair

WS1.1e,WS1.1f,WS1.1h

B2.1f describethedifferencebetweenembryonicandadultstemcellsinanimals

Researchintothedifferenttypesofstemcells.

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B2.2 The challenges of size

SummaryWhenorganismsbecomemulticellular,theneedarisesforhighlyadaptedstructuresincludinggaseousexchangesurfacesandtransportsystems,enablinglivingprocessestobeperformedeffectively.

Underlying knowledge and understandingLearnersshouldbefamiliarwiththeroleofdiffusioninthemovementofmaterialsinandbetweencells.Theyshouldalsobefamiliarwiththehumangaseousexchangesystem.

Common misconceptionsLearnershaveaviewthattheslowflowofbloodincapillariesisduetothenarrowdiameter,wheninfactitisafunctionofthetotalcross-sectionalareaofthecapillaries(1000timesgreaterthantheaorta).Whenexplainingtheimportanceoftheslowflowofbloodinallowingtimeforexchangebydiffusion,thismisunderstandingshouldbeconsidered.



BM2.2i calculatesurfacearea:volumeratios M1c

BM2.2ii usesimplecompoundmeasuressuchasrate M1aandM1c

BM2.2iii carryoutratecalculations M1aandM1c

BM2.2iv plot,drawandinterpretappropriategraphs M4a,M4b,M4candM4d



B2.2a explaintheneedforexchangesurfacesandatransportsysteminmulticellularorganismsintermsofsurfacearea:volumeratio

toincludesurfacearea,volumeanddiffusiondistances

M1c WS1.4d,WS1.4e,WS1.4f,WS2a,WS2b,WS2c,WS2d

Investigationofsurfacearea:volumeratiousinghydrochloricacidandgelatinecubesstainedwithphenolphthaleinorothersuitablepHindicator.(PAGB4,PAGB5)

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B2.2b describesomeofthesubstancestransportedintoandoutofarangeoforganismsintermsoftherequirementsofthoseorganisms

oxygen,carbondioxide,water,dissolvedfoodmolecules,mineralionsandurea

B2.2c describethehumancirculatorysystem

toincludetherelationshipwiththegaseousexchangesystem,theneedforadoublecirculatorysysteminmammalsandthearrangementofvessels

Modellingofthehumancirculatorysystem.

B2.2d explainhowthestructureoftheheartandthebloodvesselsareadaptedtotheirfunctions

thestructureofthemammalianheartwithreferencetovalves,chambers,cardiacmuscleandthestructureofbloodvesselswithreferencetothicknessofwalls,diameteroflumen,presenceofvalves

WS2a,WS2b,WS2c,WS2d

Investigationofheartstructurebydissection.

Investigationofabloodsmearusingalightmicroscope.(PAGB1,PAGB5)

Modellingofbloodusingsweetstorepresentthecomponents.

B2.2e explainhowredbloodcellsandplasmaareadaptedtotheirtransportfunctionsintheblood

WS2a,WS2b,WS2c,WS2d

Examinationofthegrossstructureofbloodvesselsusingalightmicroscope.(PAGB1)

Investigationoftheelasticityofdifferentbloodvesselsusinghangingmasses.

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B2.2f explainhowwaterandmineralionsaretakenupbyplants,relatingthestructureoftheroothaircellstotheirfunction

WS2a,WS2b,WS2c,WS2d

Examinationofroothaircellsusingalightmicroscope.(PAGB1,PAGB4)

Demonstrationoftheeffectivenessoftranspirationbytryingtosuckwaterfromabottleusinga10mstraw.(PAGB4)

Investigationofthepositionofthexylem/phloeminroot,stemandleaftissuesusingalightmicroscope.(PAGB1,PAGB4)

Interpretationofexperimentalevidenceofthemovementofdissolvedfoodmaterialsinaplant.(PAGB1,PAGB4)

Examiningthepositionofthephloeminroot,stemandleaftissuesusingalightmicroscope.(PAGB1,PAGB4)

B2.2g describetheprocessesoftranspirationandtranslocation

thestructureandfunctionofthestomata WS2a,WS2b,WS2c,WS2d

Measurementofplantstomataldensitybytakinganimpressionoftheleafusingclearnailvarnishorsprayonplaster.(PAGB1,PAGB4)

B2.2h explainhowthestructureofthexylemandphloemareadaptedtotheirfunctionsintheplant

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B2.2i explaintheeffectofavarietyofenvironmentalfactorsontherateofwateruptakebyaplant

lightintensity,airmovement,andtemperature

M1a,M1cM1d

WS2a,WS2b,WS2c,WS2d

Interpretationofexperimentalevidenceofinvestigationsintoenvironmentalfactorsthataffectwateruptake.(PAGB4)

B2.2j describehowasimplepotometercanbeusedtoinvestigatefactorsthataffecttherateofwateruptake

M1a,M1c,M1d,M4a,M4b,M4c,M4d

WS1.2b,WS1.2c,WS1.2eWS1.3a,WS1.3b,WS1.3c,WS1.3d,WS1.3e,WS1.3f,WS1.3g,WS2a,WS2b,WS2c,WS2d

Investigationoftranspirationratesfromaplantcutting.(PAGB4)

Calculationoftherateoftranspirationinvolumeofwater/time.(PAGB4)

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Topic B3: Organism level systems

B3.1 Coordination and control – the nervous system

SummaryThehumannervoussystemisanimportantpartofhowthebodycommunicateswithitselfandalsoreceivesinformationfromitssurroundings.

Underlying knowledge and understandingLearnersshouldhaveaconceptofthehierarchicalorganisationofmulticellularorganismsfromcellstotissuestoorganstosystemstoorganisms.

Common misconceptionsLearnerscommonlythinkthattheireyesseeobjects‘directly’,likeacamera,buttherealityisthattheimageformedbythebrainisbasedontheeye’sandbrain’sinterpretationofthelightthatcomesintotheeyei.e.differentpeoplewillperceivethesameobjectorimagedifferently.Younglearnersalsohavethemisconceptionthatsomesortof‘force’comesoutoftheeye,enablingittosee.




B3.1a describethestructureofthenervoussystem

CentralNervousSystem,sensoryandmotorneuronesandsensoryreceptors

Demonstrationofthestructureofaneuronebyconstructing3Dmodels.

B3.1b explainhowthecomponentsofthenervoussystemcanproduceacoordinatedresponse

itgoestoallpartsofthebody,hasmanylinks,hasdifferentsensoryreceptorsandisabletocoordinateresponses

Demonstration(byvideo)ofsomeonetryingtodoeverydaytaskswhilstbeinggivenmildelectricshocks(BBCBrainiac).

Demonstrationofreactiontimebygettingalearnertocatchafalling£5note.

Investigatingthereactiontimebyrulerdrop.(PAGB5)

B3.1c explainhowthestructureofareflexarcisrelatedtoitsfunction

M1d,WS2a,WS2b,WS2c,WS2d

Researchintoreflexes.(PAGB5)

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B3.2 Coordination and control – the endocrine system

SummaryHormonesarechemicalmessengers.Inanimals,hormonesaretransportedaroundthebodyinthebloodandaffecttargettissuesandorgans.Hormoneshaveavarietyofrolesinthehumanbody,includingcontrollingreproduction.Planthormonesarechemicalsthatregulateplantgrowthanddevelopment.Theycanbeusedinagriculturetocontroltherateofgrowth.

Underlying knowledge and understandingLearnersshouldbeawareofanumberofhormonesincludingadrenalineandthemaleandfemalesexhormones.

Common misconceptionsWithregardstothemenstrualcycle,researchhasshownthatlearnershaveproblemsrelatingthetimeofconceptiontotheconditionoftheliningoftheuterus.



BM3.2i extractandinterpretdatafromgraphs,chartsandtables M2c

BM3.2ii translateinformationbetweennumericalandgraphicalforms M4a



B3.2a describetheprinciplesofhormonalcoordinationandcontrolbythehumanendocrinesystem

useofchemicalmessengers,transportinblood,endocrineglandsandreceptors

H2g

B3.2b explain the roles of thyroxine and adrenaline in the body

thyroxine as an example of a negative feedback system

B3.2c describetheroleofhormonesinhumanreproductionincludingthecontrolofthemenstrualcycle

oestrogen,progesterone,FSHandtestosterone

WS1.3b,WS1.3e

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B3.2d explain the interactions of FSH, LH, oestrogen and progesterone in the control of the menstrual cycle

M2c,M4a Analysisofrelativehormonelevelsfromrawdataandgraphically.

B3.2e explaintheuseofhormonesincontraceptionandevaluatehormonalandnon-hormonalmethodsofcontraception

therelativeeffectivenessofthedifferentformsofcontraception

M2c,M4a WS1.1d,WS1.1e,WS1.1f

Discussionintothevariousmethodsofcontraceptionandtheireffective/ethicaluse.

B3.2f explain the use of hormones in modern reproductive technologies to treat infertility

WS1.1d,WS1.1e,WS1.1f,WS1.1h

ResearchintoXenopus laevispregnancytestingtodetecthCGbythestimulationofoogenesis.

Researchintohormonaltreatmentsforinfertility.

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B3.3 Maintaining internal environments

SummaryHomeostasisiscrucialtotheregulationofinternalenvironmentsandenablesorganismstoadapttochange,bothinternallyandexternally.Internaltemperature,bloodsugarlevelsandosmoticbalanceareregulatedbyanumberoforgansandsystemsworkingtogether.

Underlying knowledge and understandingLearnerswillbuildontheknowledgeandunderstandinggainedinsection3.1aboutcoordinationandcontrolwhenconsideringthetopicsinthissection.



BM3.3i extractandinterpretdatafromgraphs,chartsandtables M2c



B3.3a explaintheimportanceofmaintainingaconstantinternalenvironmentinresponsetointernalandexternalchange

allowingmetabolicreactionstoproceedatappropriaterates

WS1.4a Researchintohypothermia.

B3.3b explainhowinsulincontrolsbloodsugarlevelsinthebody

M2g

B3.3c explain how glucagon interacts with insulin to control blood sugar levels in the body

M2c WS2a,WS2b,WS2c,WS2d

Investigationsintotheglucosecontentoffakeurinetodiagnosediabetes,usinge.g.Clinistix.(PAGB5)

B3.3d comparetype1andtype2diabetesandexplainhowtheycanbetreated

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Topic B4: Community level systems

B4.1 Ecosystems

SummaryMicroorganismsplayanimportantroleinthecontinuouscyclingofchemicalsinecosystems.Bioticandabioticfactorsinteractinanecosystemandhaveaneffectoncommunities.Livingorganismsformpopulationsofsinglespecies,communitiesofmanyspeciesandarepartofecosystems.Livingorganismsareinterdependentandshowadaptationstotheirenvironment.Feedingrelationshipsreflectthestabilityofanecosystemandindicatetheflowofbiomassthroughtheecosystem.

Underlying knowledge and understandingLearnersshouldbefamiliarwiththeideaofafoodwebandtheinterrelationshipsassociatedwiththemandthatvariationallowslivingthingstosurviveinthesameecosystem.Theyshouldalsorecognisethatorganismsaffecttheirenvironmentandareaffectedbyit.

Common misconceptionsResearchhasshownthatitiseasierforalearnertoexplaintheconsequencesonafoodwebiftheproducersareremovedforsomereasonthanifthetoppredatorsaretakenaway.Itisalsobettertostartoffexplainingideasrelatingtofoodwebsusingsmallsimplewebswithanimalsandplantsthatlearnersarelikelytoknowe.g.rabbitsandfoxes.Learnersfindarrowsshowingtheflowofbiomassfromonetrophicleveltoanotherquitechallengingandoftenmistakeitforthedirectionofpredation.Thismakesproblemsrelatingtothemanipulationofafoodwebquitedifficultforsome.



BM4.1i Calculatethepercentageofmass M1c

BM4.1ii Plotanddrawappropriategraphsselectingappropriatescalesfortheaxes M4aandM4c

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B4.1a recallthatmanydifferentmaterialscyclethroughtheabioticandbioticcomponentsofanecosystem

examplesofcycledmaterialse.g.nitrogenandcarbon

B4.1b explaintheroleofmicroorganismsinthecyclingofmaterialsthroughanecosystem

theroleofmicroorganismsindecomposition

Researchintotherangeofecosystemsandexamplesofmicro-organismsthatactasdecomposerswithinthem.(PAGB1,PAGB2,PAGB3,PAGB5)

B4.1c explaintheimportanceofthecarboncycleandthewatercycletolivingorganisms

maintaininghabitats,freshwaterflowofnutrients

B4.1d describedifferentlevelsoforganisationinanecosystemfromindividualorganismstothewholeecosystem

M1c

B4.1e explainhowabioticandbioticfactorscanaffectcommunities

temperature,lightintensity,moisturelevel,pHofsoil,predators,food

M4a,M4c,M3a

WS1.3a,WS1.3b,WS1.3eWS1.3h,WS2a,WS2b,WS2c,WS2d

Identificationofthebioticfactorsinanecosystemusingsamplingtechniques.(PAGB2)

B4.1f describetheimportanceofinterdependenceandcompetitioninacommunity

interdependencerelatingtopredation,mutualismandparasitism

WS1.4a Examinationoftherootsofaleguminousplante.g.clovertoobservetherootnodules.(PAGB1)

Investigationofthehollyleafminerorthehorse-chestnutleafminer(Cameraria ohridella).(PAGB1,PAGB2)

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Topic B5: Genes, inheritance and selection

B5.1 Inheritance

SummaryInheritancereliesonthegeneticinformationcontainedinthegenomebeingpassedfromonegenerationtothenext,whethersexuallyorasexually.Thecharacteristicsofalivingorganismareinfluencedbythegenomeanditsinteractionwiththeenvironment.

Underlying knowledge and understandingLearnersshouldbefamiliarwiththeideaofheredityastheprocessbywhichgeneticinformationispassedfromonegenerationtothenext.Theyshouldhaveasimplemodelofchromosomes,genesandDNA.

Common misconceptionsLearnerscommonlystruggletoappreciatethephysicalrelationshipsbetweenthenucleus,geneticmaterial,thegenome,chromosomesandgenes.Accuratedefinitionsofthesetermswillhelplearners’explanationsinthistopic.Learners

oftenhavewell-developed(althoughnotnecessarilyscientificallyaccurate)explanationsforinheritancebeforeundertakingGCSEstudy.Someexamplesincludethatintra-specificvariationisasaresultofdefectsindevelopmentorthatacquiredcharacteristicscanbeinherited.Caremustalsobetakenwiththeconceptofdominantandrecessivealleles.Whetheranalleleisdominantorrecessivedoesnotaffectthemechanismofinheritanceoftheallele,butisanobservedpatterninthephenotypeoforganisms.Manylearnersassumethatthedominantallele‘dominates’therecessiveallelepreventingitsexpression(whichisnotthecase)orthattherecessivealleleisactuallyjustanabsenceofthedominantallele(alsonotgenerallythecase).



BM5.1i understandandusedirectproportionsandsimpleratiosingeneticcrosses M1c

BM5.1ii understandandusetheconceptofprobabilityinpredictingtheoutcomeofgeneticcrosses M2e

BM5.1iii extractandinterpretinformationfromcharts,graphsandtables M2candM4a

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B5.1a explainthefollowingterms:gamete,chromosome,gene,allele/variant,dominant,recessive,homozygous,heterozygous,genotypeandphenotype

Useofallelestoworkoutthephenotypeofprogeny.

B5.1b describethegenomeastheentiregeneticmaterialofanorganism

B5.1c describethatthegenome,anditsinteractionwiththeenvironment,influencethedevelopmentofthephenotypeofanorganism

useofexamplesofdiscontinuousandcontinuousvariatione.g.eyecolour,weightandheight

B5.1d recallthatallvariantsarisefrommutations,andthatmosthavenoeffectonthephenotype,someinfluencephenotypeandaveryfewdeterminephenotype

B5.1e explainthetermshaploidanddiploid

B5.1f explaintheroleofmeioticcelldivisioninhalvingthechromosomenumbertoformgametes

thatthismaintainsdiploidcellswhengametescombineandisasourceofgeneticvariation

B5.1g explainsinglegeneinheritance inthecontextofhomozygousandheterozygouscrossesinvolvingdominantandrecessivegenes

M2c,M4a Predictionoftheprobabilityofphenotypeforgeneticcrosses.

Investigationintoprobabilitybysuitableexample(e.g.cointossordieroll).

B5.1h predicttheresultsofsinglegenecrosses M1c,M2c,M2e,M4a

B5.1i describesexdeterminationinhumansusingageneticcross

M1c,M2c,M2e,M4a

B5.1j recallthatmostphenotypicfeaturesaretheresultofmultiplegenesratherthansinglegeneinheritance

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B5.2 Natural selection and evolution

SummaryVariationinthegenomeandchangesintheenvironmentdrivetheprocessofnaturalselection,leadingtochangesinthecharacteristicsofpopulations.Evolutionaccountsforbothbiodiversityandhoworganismsareallrelatedtovaryingdegrees.Keyindividualshaveplayedimportantrolesinthedevelopmentoftheunderstandingofgenetics.

Underlying knowledge and understandingLearnersshouldappreciatethatchangesintheenvironmentcanleavesomeindividuals,orevensomeentirespecies,unabletocompeteandreproduceleadingtoextinction.

Common misconceptionsLearnersareusedtohearingthetermevolutionineverydaylifebutitisoftenusedforitemsthathavebeendesignedandgraduallyimprovedinordertofitapurpose.Theythereforefinditdifficulttograsptheideathatevolutionbynaturalselectionreliesonrandommutations.Learnersalsotendtoimplythatindividualschangebynaturalselection.Statementssuchas‘amothwillchangebynaturalselectioninordertobecomebettercamouflaged’includebothofthesecommonmisconceptions.




B5.2a statethatthereisusuallyextensivegeneticvariationwithinapopulationofaspecies

B5.2b describetheimpactofdevelopmentsinbiologyonclassificationsystems

naturalandartificialclassificationsystemsanduseofmolecularphylogeneticsbasedonDNAsequencing

WS1.1b

B5.2c explainhowevolutionoccursthroughthenaturalselectionofvariantsthathavegivenrisetophenotypesbestsuitedtotheirenvironment

theconceptofmutation

B5.2d describeevolutionasachangeintheinheritedcharacteristicsofapopulationovertime,throughaprocessofnaturalselection,whichmayresultintheformationofnewspecies

B5.2e describetheevidenceforevolution fossilsandantibioticresistanceinbacteria

WS1.1cWS1.1dWS1.1g

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Topic B6: Global challenges

Thistopicseekstointegratelearners’knowledgeandunderstandingofbiologicalsystemsandprocesses,withtheaimofapplyingittoglobalchallenges.Biologicalinformationisusedtohelppeopletoimprovetheirownlivesandstrivetocreate

asustainableworldforfuturegenerations.Thistopicprovidesopportunitiestodrawtogethertheconceptscoveredinearliertopics,allowingsynoptictreatmentofthesubject.

6.1 Monitoring and maintaining the environment

SummaryLivingorganismsinteractwitheachother,theenvironmentandwithhumansinmanydifferentways.Ifthevarietyoflifeistobemaintainedwemustactivelymanageourinteractionswiththeenvironment.Wemustmonitorourenvironment,collectingandinterpretinginformationaboutthenaturalworld,toidentifypatternsandrelatepossiblecauseandeffect.

Underlying knowledge and understandingFromtheirstudyintopic4,learnersshouldbefamiliarwithecosystemsandthevariouswaysorganismsinteract.Theyshouldunderstandhowbioticandabiotic

factorsinfluencecommunities.Learnersshouldbefamiliarwiththegasesoftheatmospherefromkeystage3.

Common misconceptionsItisimportantthatinthestudyofthistopiclearnersaregivenopportunitiestoexplorebothpositiveandnegativehumaninteractionswithinecosystems.



BM6.1i calculatearithmeticmeans M2b

BM6.1ii plotanddrawappropriategraphsselectingappropriatescalesfortheaxes M4aandM4c

BM6.1iii understandandusepercentiles M1c

BM6.1iv extractandinterpretinformationfromcharts,graphsandtables M2candM4a

BM6.1v understandtheprinciplesofsamplingasappliedtoscientificdata M2d

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B6.1a explainhowtocarryoutafieldinvestigationintothedistributionandabundanceoforganismsinahabitatandhowtodeterminetheirnumbersinagivenarea

samplingtechniques(randomandtransects,capture-recapture),useofquadrats,pooters,nets,keysandscalingupmethods

M1c,M2b,M2cM4a,M4c

WS1.2d,WS1.2b,WS1.2c,WS1.2e,WS1.3h,WS2a,WS2b,WS2c,WS2d

Investigationofecologicalsamplingmethods.Usethesymbols=,,Ä,~inyouranswerwhereappropriate.(PAGB2)

Investigationofsamplingusingasuitablemodel(e.g.measuringtheredsweetsinamixedselection).

B6.1b describebothpositiveandnegativehumaninteractionswithinecosystemsandexplaintheirimpactonbiodiversity

theconservationofindividualspeciesandselectedhabitatsandthreatsfromlanduseandhunting

WS2a,WS2b,WS2c,WS2d

Investigationintotheeffectivenessofgerminationindifferentstrengthsofacidrain.(PAGB4)

Investigationintotheeffectsofpollutiononlichendistribution.(PAGB2)

B6.1c explainsomeofthebenefitsandchallengesofmaintaininglocalandglobalbiodiversity

thedifficultyingainingagreementsforandthemonitoringofconservationschemesalongwiththebenefitsofecotourism

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B6.2 Feeding the human race

SummaryThehumanpopulationisincreasingrapidlyandwiththiscomesaneedformorefood.Biologistsareseekingtotacklethisincreaseddemand,whichwillleadtoanimprovementinthelivesofmanypeoplearoundtheworld.However,therearemanythingstoconsiderinachievingthisaim,notleasttheimpactonecosystems.Thereismuchdebatesurroundingtheuseofgenetechnologyasapotentialsolutiontotheproblemoffoodsecurity.

Underlying knowledge and understandingLearnersshouldbefamiliarwiththecontentofahealthyhumandietandtheconsequencesofimbalancesinahealthydailydiet.Theirknowledgeandunderstandingfromtopics1,4and5willalsobedrawntogetherinthistopic.

ThisincludestheorganisationofDNA,whatplantsrequireenablingthemtophotosynthesise,interactionsbetweenspeciesandtheideaofvariabilitywithinspeciesandsubsequentselectionofcharacteristics.

Common misconceptionsLearnerscanoftenthinkthatgeneticengineeringleadstotheincreaseduseofpesticides.



BM6.2 extractandinterpretinformationfromcharts,graphsandtables M2candM4a



B6.2a explaintheimpactoftheselectivebreedingoffoodplantsanddomesticatedanimals

M2c,M4a WS1.1c ResearchintotheRothamsted Research Broadbalkexperiment.

B6.2b describegeneticengineeringasaprocesswhichinvolvesmodifyingthegenomeofanorganismtointroducedesirablecharacteristics

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B6.2c describe the main steps in the process of genetic engineering

restriction enzymes, sticky ends, vectors e.g. plasmids, ligase, host bacteria and selection using antibiotic resistance markers

Productionofastoryboarddescribingtheprocessesforgeneticengineering.

B6.2d explainsomeofthepossiblebenefitsandrisksofusinggenetechnologyinmodernagriculture

toincludepracticalandethicalconsiderations

WS1.1cWS1.1d,WS1.1e,WS1.1f,WS1.1g,WS1.1h,WS1.3i

Researchintotheadvantagesanddisadvantagesofselectivebreedingandgeneticengineering.

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B6.3 Monitoring and maintaining health

SummaryDiseasesaffectthehealthofpopulationsofbothhumansandplants.Scientistsareconstantlyonthelookoutforwaysofpreventingandcombatingdisease.Thepreventionofdiseaseinplantsisimportantsothatweareabletogrowhealthyplantsenablingustofeedourselvesandenhanceourenvironment.Theunderstandingofhowdiseaseisspread,howourbodiesdefendthemselvesagainstdiseaseandhowimmunityisachievedisessentialtoenableustocombatpotentiallyfataldiseasesspreadingthroughoutwholepopulations.Non-communicablediseasesalsohaveanimpactonthehealthofthepopulation.Thepreventionofthesediseasesisfrequentlydiscussedinthemedia,withadvicebeinggiventousonhowtoreduceourriskofcontractingthesediseasesthroughourlife-stylechoicesanddiscussionofnewtechnologies.

Underlying knowledge and understandingLearnersshouldbefamiliarwiththeeffectsof‘recreational’drugs(includingsubstancemisuse)onbehaviour,healthandlifeprocesses,theimpactofexercise,

asthmaandsmokingonthegasexchangesystemandtheconsequencesofimbalancesinthediet,includingobesity,starvationanddeficiencydiseases.

Common misconceptionsResearchhasshownthatlearnerstendtoviewallmicro-organismsasbeingnon-beneficial.Theytendtoconsiderhealthasjustphysicalanddonotconsidermentalhealth.Learnersalsoconfusewhichdiseasesareinheritedandwhicharecaught.Theyseecancerasageneticdisease.



BM6.3i translateinformationbetweengraphicalandnumericalforms M4a

BM6.3ii constructandinterpretfrequencytablesanddiagrams,barchartsandhistograms M2c

BM6.3iii understandtheprinciplesofsamplingasappliedtoscientificdata M2d

BM6.3iv useascatterdiagramtoidentifyacorrelationbetweentwovariables M2g

BM6.3v calculatecross-sectionalareasofbacterialculturesandclearagarjellyusingπr2 M5c

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B6.3a describetherelationshipbetweenhealthanddisease

B6.3b describedifferenttypesofdiseases communicableandnon-communicablediseases

B6.3c describetheinteractionsbetweendifferenttypesofdisease

HIVandtuberculosis,andHPVandcervicalcancer

M4a

B6.3d explainhowcommunicablediseases(causedbyviruses,bacteria,protistsandfungi)arespreadinanimalsandplants

scientificquantities,numberofpathogens,numberofinfectedcases,estimatingthenumberofcases

M2c WS1.4b

B6.3e explainhowthespreadofcommunicablediseasesmaybereducedorpreventedinanimalsandplants

detectionoftheantigen,DNAtesting,visualidentificationofthedisease

M2c WS1.4b

B6.3f describeaminimumofonecommonhumaninfection,oneplantdiseaseandsexuallytransmittedinfectionsinhumansincludingHIV/AIDS

plantdiseases:virustobaccomosaicvirus,fungalErysiphe graminisbarleypowderymildew,bacterialAgrobacterium tumafacienscrowngalldisease

B6.3g explainhowwhitebloodcellsandplateletsareadaptedtotheirdefencefunctionsintheblood

B6.3h describethenon-specificdefencesystemsofthehumanbodyagainstpathogens

B6.3i explaintheroleoftheimmunesystemofthehumanbodyindefenceagainstdisease

B6.3j explaintheuseofvaccinesandmedicinesinthepreventionandtreatmentofdisease

antibiotics,antiviralsandantiseptics WS1.1g,WS1.1h Researchintowhetherchildrenshouldberoutinelyvaccinated.

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B6.3k describetheprocessesofdiscoveryanddevelopmentofpotentialnewmedicines

preclinicalandclinicaltesting M2d,M5c,M3d

WS1.1d,WS2a,WS2b,WS2c,WS2d

Investigationintothegrowthofbacterialculturesusingaseptictechniques.(PAGB1)

B6.3l recallthatmanynon-communicablehumandiseasesarecausedbytheinteractionofanumberoffactors

cardiovasculardiseases,manyformsofcancer,somelung(bronchitis)andliver(cirrhosis)diseasesanddiseasesinfluencedbynutrition,includingtype2diabetes

B6.3m evaluatesomedifferenttreatmentsforcardiovasculardisease

lifestyle,medicalandsurgical

B6.3n analysetheeffectoflifestylefactorsontheincidenceofnon-communicablediseasesatlocal,nationalandgloballevels

lifestylefactorstoincludeexercise,diet,alcoholandsmoking

M2d,M2g,M4a

B6.3o describecancerastheresultofchangesincellsthatleadtouncontrolledgrowthanddivision

B6.3p discusspotentialbenefitsandrisksassociatedwiththeuseofstemcellsinmedicine

tissuetransplantationandrejection WS1.1c,WS1.1d,WS1.1e,WS1.1f,WS1.1g,WS1.1hWS1.1j

B6.3q explainsomeofthepossiblebenefitsandrisksofusinggenetechnologyinmedicine

practicalandethicalconsiderations WS1.1c,WS1.1d,WS1.1eWS1.1j

B6.3r discussthepotentialimportanceformedicineofourincreasingunderstandingofthehumangenome

theideasofpredictingthelikelihoodofdiseasesoccurringandtheirtreatmentbydrugswhicharetargetedtogenomes

WS1.1cWS1.1d,WS1.1j

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Topic C1: Particles

C1.1 The particle model

SummaryThisshortsectionintroducestheparticlemodelanditsexplanationofdifferentstatesofmatter.Asimpleparticlemodelcanbeusedtorepresentthearrangementofparticlesinthedifferentstatesofmatterandtoexplainobservationsduringchangesinstate.Itdoesnot,however,explainwhydifferentmaterialshavedifferentproperties.Thisexplanationisthattheparticlesthemselvesandhowtheyareheldtogethermustbedifferentinsomeway.Elementsaresubstancesthataremadeupofonlyonetypeofatomandatomsofdifferentelementscancombinetomakecompounds.

Underlying knowledge and understandingLearnersshouldbefamiliarwiththedifferentstatesofmatterandtheirproperties.Theyshouldalsobefamiliarwithchangesofstateintermsoftheparticlemodel.Learnersshouldhavesufficientgroundingintheparticlemodeltobeabletoapplyittounfamiliarmaterialsandcontexts.

Common misconceptionsLearnerscommonlyintuitivelyadheretotheideathatmatteriscontinuous.Forexample,theybelievethatthespacebetweengasparticlesisfilledornon-existent,orthatparticlesexpandwhentheyareheated.Thenotionthatemptyspaceexistsbetweenparticlesisproblematicbecausethislackssupportingsensoryevidence.Theyalsoshowdifficultyunderstandingtheconceptofchangesinstatebeingreversible;thisshouldbeaddressedduringtheteachingofthistopic.


Reference Mathematical learning outcomes Mathematical skills

CM1.1i representthree-dimensionalshapesintwodimensionsandviceversawhenlookingatchemicalstructurese.g.allotropesofcarbon

M5b

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C1.1a describethemainfeaturesoftheparticlemodelintermsofstatesofmatterandchangeofstate

M5b WS1.1a,WS1.1b

C1.1b explainintermsoftheparticlemodelthedistinctionbetweenphysicalchangesandchemicalchanges

C1.1c explain the limitations of the particle model in relation to changes of state when particles are represented by inelastic spheres (e.g. like bowling balls)

that it does not take into account the forces of attraction between particles, the size of particles and the space between them

M5b WS1.1c Observationsofchangeofstatewithcomparisontochemicalchanges.

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C1.2 Atomic structure

SummaryAnatomisthesmallestcomponentofanelementthatgivesanelementitsproperty.Thesepropertiescanbeexplainedbymodelsofatomicstructure.Currentmodelssuggestthatatomsaremadeofsmallersub-atomicparticlescalledprotons,neutronsandelectrons.Theysuggestthatatomsarecomposedofanucleussurroundedbyelectrons.Thenucleusiscomposedofneutronsandprotons.Atomsofeachelementhavethesamenumberofprotonsaselectrons.Atomsofdifferentelementshavedifferentnumbersofprotons.Atomsofthesameelementwillhavethesamenumberofprotonsbutmayhavedifferentnumbersofneutrons.

Underlying knowledge and understandingLearnersshouldbefamiliarwiththesimple(Dalton)atomicmodel.

Common misconceptionsLearnerscommonlyhavedifficultyunderstandingtheconceptofisotopesduetothefacttheythinkthatneutralatomshavethesamenumberofprotonsandneutrons.Theyalsofinditdifficulttodistinguishbetweenthepropertiesofatomsandmolecules.Anothercommonmisconceptionisthatapositiveiongainsprotonsoranegativeionloseselectronsi.e.thatthereisachangeinthenucleusoftheatomratherthanachangeinthenumberofelectrons.


Reference Mathematical learning outcomes Mathematical skills

CM1.2i relatesizeandscaleofatomstoobjectsinthephysicalworld M4a

CM1.2ii estimatesizeandscaleofatoms M1c

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C1.2a describehowandwhytheatomicmodelhaschangedovertime

themodelsofDalton,Thomson,Rutherford,Bohr,GeigerandMarsden

WS1.1a,WS1.1i,WS1.2b

Timelineoftheatomicmodel.

C1.2b describetheatomasapositivelychargednucleussurroundedbynegativelychargedelectrons,withthenuclearradiusmuchsmallerthanthatoftheatomandwithmostofthemassinthenucleus

WS1.4a

C1.2c recallthetypicalsize(orderofmagnitude)ofatomsandsmallmolecules

theconceptthattypicalatomicradiiandbondlengthareintheorderof10–10m

M1c,M4a WS1.1c,WS1.4b,WS1.4c,WS1.4d,WS1.4e,WS1.4f

C1.2d recallrelativechargesandapproximaterelativemassesofprotons,neutronsandelectrons

WS1.4a,WS1.4b,WS1.4c

C1.2e calculatenumbersofprotons,neutronsandelectronsinatomsandions,givenatomicnumberandmassnumberofisotopes

definitionsofanion,atomicnumber,massnumberandanisotope,alsothestandardnotationtorepresentthese

WS1.3c,WS1.4b

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Topic C2: Elements, compounds and mixtures

C2.1 Purity and separating mixtures

SummaryInchemicaltermselementsandcompoundsarepuresubstancesandmixturesareimpuresubstances.Chemicallypuresubstancescanbeidentifiedusingmeltingpoint.Manyusefulmaterialsthatweusetodayaremixtures.Therearemanymethodsofseparatingmixturesincludingfiltration,crystallisation,distillationandchromatographictechniques.

Underlying knowledge and understandingLearnersshouldbefamiliarwiththeconceptofpuresubstances.Theyshouldhavemetsimpleseparationtechniquesofmixtures.Theidentificationofpuresubstancesintermsofmeltingpoint,boilingpointandchromatographywillalsohavebeenmetbefore.

Common misconceptionsLearnerscommonlymisusethewordpureandconfuseitwithnaturalsubstancesorasubstancethathasnotbeentamperedwith.Theythinkthatwhenasubstancedissolvesthatthesolutionispureandnotamixture.



CM2.1i arithmeticcomputation,ratio,percentageandmultistepcalculationspermeatesquantitativechemistry M1a,M1c,M1d

CM2.1ii provideanswerstoanappropriatenumberofsignificantfigures M2a

CM2.1iii changethesubjectofamathematicalequation M3b,M3c

CM2.1iv arithmeticcomputationandratiowhendeterminingempiricalformulae,balancingequations M3b,M3c

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C2.1a explainwhatismeantbythepurityofasubstance,distinguishingbetweenthescientificandeverydayuseoftheterm‘pure’

WS1.4a Purificationofcompounds.(PAGC3,PAGC4)

C2.1b usemeltingpointdatatodistinguishpurefromimpuresubstances

M1a,M1c,M1d,M2a

Measurementofmeltingpoint.

C2.1c calculaterelativeformulamassesofspeciesseparatelyandinabalancedchemicalequation

thedefinitionofrelativeatomicmass,relativemolecularmassandrelativeformulamass

M3b,M3c WS1.3c,WS1.4c

C2.1d deducetheempiricalformulaofacompoundfromtherelativenumbersofatomspresentorfromamodelordiagramandviceversa

M3b,M3c WS1.1b,WS1.4a

C2.1e explainthatmanyusefulmaterialsareformulationsofmixtures

alloys

C2.1f describe,explainandexemplifytheprocessesoffiltration,crystallisation,simpledistillation,andfractionaldistillation

knowledgeofthetechniquesoffiltration,crystallisation,simpledistillationandfractionaldistillation

WS1.2b,WS1.2c,WS2a,WS2b

Separationofmixturesandpurificationofcompounds.(PAGC3,PAGC4)

Distillationofmixtures(PAGC3)

C2.1g describethetechniquesofpaperandthinlayerchromatography

WS1.2b,WS1.2c,WS1.4a,WS2a,WS2b

Thinlayerchromatography.(PAGC2)

C2.1h recallthatchromatographyinvolvesastationaryandamobilephaseandthatseparationdependsonthedistributionbetweenthephases

identificationofthemobileandstationaryphases

WS1.4a

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C2.1i interpretchromatograms,includingmeasuringRfvalues

therecallandtheuseoftheformula M3b,M3c WS1.3c,WS1.4a

C2.1j suggestsuitablepurificationtechniquesgiveninformationaboutthesubstancesinvolved

C2.1k suggestchromatographicmethodsfordistinguishingpurefromimpuresubstances

paper,thinlayer(TLC)andgaschromatography

WS1.4a Usingchromatographytoidentifymixturesofdyesinanunknownink.(PAGC2)

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C2.2 Bonding

SummaryAsimpleelectronenergylevelmodelcanbeusedtoexplainthebasicchemicalpropertiesofelements.Whenchemicalreactionsoccur,theycanbeexplainedintermsoflosing,gainingorsharingofelectrons.Theabilityofanatomtolose,gainorshareelectronsdependsonitsatomicstructure.Atomsthatloseelectronswillbondwithatomsthatgainelectrons.Electronswillbetransferredbetweentheatomstoformapositiveionandanegativeion.Theseionsattractoneanotherinwhatisknownasanionicbond.Atomsthatshareelectronscanbondwithotheratomsthatshareelectronstoformamolecule.Atomsinthesemoleculesareheldtogetherbycovalentbonds.

Underlying knowledge and understandingLearnersshouldbefamiliarwiththesimple(Dalton)atomicmodel.

Common misconceptionsLearnersdonotalwaysappreciatethatthenucleusofanatomdoesnotchangewhenanelectronislost,gainedorshared.Theyalsofinditdifficulttopredictthenumbersofatomsthatmustbondinordertoachieveastableouterlevelofelectrons.Learnersthinkthatchemicalbondsarephysicalthingsmadeofmatter.TheyalsothinkthatpairsofionssuchasNa+andCl –aremolecules.Theydonothaveanawarenessofthe3Dnatureofbondingandthereforetheshapeofmolecules.



CM2.2i estimatesizeandscaleofatoms M1c

CM2.2ii representthree-dimensionalshapesintwodimensionsandviceversawhenlookingatchemicalstructurese.g.allotropesofcarbon

M5b

CM2.2iii translateinformationbetweendiagrammaticandnumericalforms M4a

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C2.2a describemetalsandnon-metalsandexplainthedifferencesbetweenthemonthebasisoftheircharacteristicphysicalandchemicalproperties

physicalproperties,formationofionsandcommonreactionse.g.withoxygentoformoxides

WS1.3f,WS1.4a

C2.2b explainhowtheatomicstructureofmetalsandnon-metalsrelatestotheirpositioninthePeriodicTable

C2.2c explainhowthepositionofanelementinthePeriodicTableisrelatedtothearrangementofelectronsinitsatomsandhencetoitsatomicnumber

groupnumberandperiodnumber M1c WS1.4a

C2.2d describeandcomparethenatureandarrangementofchemicalbondsin: i. ioniccompoundsii. simplemoleculesiii. giantcovalentstructuresiv. polymersv. metals

M5b,M4a WS1.4a Makeballandstickmodelsofmolecules.

C2.2e explainchemicalbondingintermsofelectrostaticforcesandthetransferorsharingofelectrons

WS1.4a

C2.2f constructdotandcrossdiagramsforsimplecovalentandbinaryionicsubstances

M4a WS1.4a

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C2.2g describethelimitationsofparticularrepresentationsandmodels

dotandcrossdiagrams,ballandstickmodelsandtwo-andthree-dimensionalrepresentations

M5b WS1.1c

C2.2h explainhowthereactionsofelementsarerelatedtothearrangementofelectronsintheiratomsandhencetotheiratomicnumber

WS1.1b,WS1.3f,WS1.4a

C2.2i explainintermsofatomicnumberhowMendeleev’sarrangementwasrefinedintothemodernPeriodicTable

WS1.1a,WS1.4a

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C2.3 Properties of materials

SummaryThissectionexploresthephysicalpropertiesofelementsandcompoundsandhowthenatureoftheirbondingisafactorintheirproperties.

Underlying knowledge and understandingLearnerswillknowthedifferencebetweenanatom,elementandcompound.

Common misconceptionsLearnerscommonlyhavealimitedunderstandingofwhatcanhappenduringchemicalreactions,forexample,thatsubstancesmayexplode,burn,contract,expandorchangestate.



CM2.3i representthree-dimensionalshapesintwodimensionsandviceversawhenlookingatchemicalstructurese.g.allotropesofcarbon

M5b

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C2.3a recallthatcarboncanformfourcovalentbonds WS1.4a

C2.3b explainthatthevastarrayofnaturalandsyntheticorganiccompoundsoccurduetotheabilityofcarbontoformfamiliesofsimilarcompounds,chainsandrings

C2.3c explainthepropertiesofdiamond,graphite,fullerenesandgrapheneintermsoftheirstructuresandbonding

M5b WS1.4a

C2.3d useideasaboutenergytransfersandtherelativestrengthofchemicalbondsandintermolecularforcestoexplainthedifferenttemperaturesatwhichchangesofstateoccur

WS1.2a,WS1.3f,WS1.4a,WS1.4c

C2.3e usedatatopredictstatesofsubstancesundergivenconditions

datasuchastemperatureandhowthismaybelinkedtochangesofstate

C2.3f explainhowthebulkpropertiesofmaterials(ioniccompounds;simplemolecules;giantcovalentstructures;polymersandmetals)arerelatedtothedifferenttypesofbondstheycontain,theirbondstrengthsinrelationtointermolecularforcesandthewaysinwhichtheirbondsarearranged

recognitionthattheatomsthemselvesdonothavethebulkpropertiesofthesematerials

WS1.4a

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Topic C3: Chemical reactions

C3.1 Introducing chemical reactions

SummaryAchemicalequationrepresents,insymbolicterms,theoverallchangeinachemicalreaction.Newmaterialsareformedthroughchemicalreactionsbutmasswillbeconserved.Thiscanbeexplainedbyamodelinvolvingtherearrangementofatoms.Avogadrogaveusasystemofmeasuringtheamountofasubstanceinmoles.

Underlying knowledge and understandingLearnersshouldbefamiliarwithchemicalsymbolsandformulaeforelementsandcompounds.Theyshouldalsobefamiliarwithrepresentingchemicalreactionsusingformulae.Learnerswillhaveknowledgeofconservationofmass,changesofstateandchemicalreactions.

Common misconceptionsAlthoughlearnersmayhavemettheconservationofmasstheystilltendtorefertochemicalreactionsaslosingmass.Theyunderstandthatmassisconservedbutnotthenumberorspeciesofatoms.Theymaythinkthattheoriginalsubstancevanishes‘completelyandforever’inachemicalreaction.



CM3.1i arithmeticcomputationandratiowhendeterminingempiricalformulae,balancingequations M1a,M1c

CM3.1ii calculations with numbers written in standard form when using the Avogadro constant M1b

CM3.1iii provideanswerstoanappropriatenumberofsignificantfigures M2a

CM3.1iv convertunitswhereappropriateparticularly from mass to moles M1c

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C3.1a usechemicalsymbolstowritetheformulaeofelementsandsimplecovalentandioniccompounds

M1a,M1c WS1.4a

C3.1b usethenamesandsymbolsofcommonelementsandcompoundsandtheprincipleofconservationofmasstowriteformulaeandbalancedchemicalequationsand half equations

M1a,M1c WS1.4c

C3.1c usethenamesandsymbolsofcommonelementsfromasuppliedPeriodicTabletowriteformulaeandbalancedchemicalequationswhereappropriate

thefirst20elements,Groups1,7,and0andothercommonelementsincludedwithinthespecification

C3.1d usetheformulaofcommonionstodeducetheformulaofacompound

M1a,M1c

C3.1e construct balanced ionic equations M1a,M1c

C3.1f describethephysicalstatesofproductsandreactantsusingstatesymbols(s,l,gandaq)

C3.1g describeteststoidentifyselectedgases oxygen,hydrogen,carbondioxideandchlorine

C3.1h recall and use the definitions of the Avogadro constant (in standard form) and of the mole

the calculation of the mass of one atom/molecule

M1b,M1c WS1.4b,WS1.4c,WS1.4d,WS1.4f

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C3.1i explain how the mass of a given substance is related to the amount of that substance in moles and vice versa

M1c,M2a WS1.4b,WS1.4c

C3.1j explain how the mass of a solute and the volume of the solution is related to the concentration of the solution

M1b,M1c WS1.3c,WS1.4a,WS1.4c

C3.1k recallandusethelawofconservationofmass WS1.4c

C3.1l explainanyobservedchangesinmassinnon-enclosedsystemsduringachemicalreactionandexplainthemusingtheparticlemodel

WS1.1b,WS1.4c

C3.1m deduce the stoichiometry of an equation from the masses of reactants and products and explain the effect of a limiting quantity of a reactant

M1c WS1.3c,WS1.4c,WS1.4d,WS1.4f

C3.1n use a balanced equation to calculate masses of reactants or products

M1c WS1.3c,WS1.4c

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C3.2 Energetics

SummaryChemicalreactionsareaccompaniedbyanenergychange.Asimplemodelinvolvingthebreakingandmakingofchemicalbondscanbeusedtointerpretandcalculatetheenergychange.

Underlying knowledge and understandingLearnersshouldbefamiliarwithexothermicandendothermicchemicalreactions.

Common misconceptionsLearnerscommonlyhavetheideathatenergyislostorusedup.Theydonotgrasptheideathatenergyistransferred.Learnersalsowronglythinkthatenergy

isreleasedwhenbondsbreakanddonotlinkthisreleaseofenergywiththeformationofbonds.Theyalsomaythinkforexamplethatacandleburningisendothermicbecauseheatisneededtoinitiatethereaction.



CM3.2i interpretationofchartsandgraphswhendealingwithreactionprofiles M4a

CM3.2ii arithmeticcomputationwhencalculatingenergychanges M1a

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C3.2a distinguishbetweenendothermicandexothermicreactionsonthebasisofthetemperaturechangeofthesurroundings

WS1.4c Measuringthetemperaturechangeinreactions.(PAGC5)

C3.2b drawandlabelareactionprofileforanexothermicandanendothermicreaction

activationenergy,energychange,reactantsandproducts

M4a WS1.3b,WS1.3c,WS1.3d,WS1.3e,WS1.3g,WS1.3h,WS1.4c

C3.2c explainactivationenergyastheenergyneededforareactiontooccur

WS1.4c

C3.2d calculate energy changes in a chemical reaction by considering bond making and bond breaking energies

M1a WS1.3c,WS1.4c

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C3.3 Types of chemical reactions

SummaryChemicalreactionscanbeclassifiedaccordingtochangesattheatomicandmolecularlevel.Examplesoftheseincludereduction,oxidationandneutralisationreactions.

Underlying knowledge and understandingLearnersshouldbefamiliarwithcombustion,thermaldecomposition,oxidationanddisplacementreactions.Theywillbefamiliarwithdefiningacidsandalkalisintermsofneutralisationreactions.Learnerswillhavemetreactionsofacidswithalkalistoproduceasaltandwaterandreactionsofacidswithmetalstoproduceasaltandhydrogen.

Common misconceptionsLearnerscommonlyintuitivelyadheretotheideathathydrogenionsinanacidarestillpartofthemolecule,notfreeinthesolution.TheytendtohavelittleunderstandingofpH,forexample,theytendtothinkthatalkalisarelesscorrosivethanacids.Learnersalsomaythinkthatthestrengthofacidsandbasesandconcentrationmeanthesamething.



CM3.3i arithmeticcomputation,ratio,percentageandmultistepcalculationspermeatesquantitativechemistry M1a,M1c,M1d



C3.3a explainreductionandoxidationintermsoflossorgainofoxygen,identifyingwhichspeciesareoxidisedandwhicharereduced

theconceptofoxidisingagentandreducingagent

WS1.4a

C3.3b explain reduction and oxidation in terms of gain or loss of electrons, identifying which species are oxidised and which are reduced

WS1.4a

C3.3c recallthatacidsformhydrogenionswhentheydissolveinwaterandsolutionsofalkaliscontainhydroxideions

WS1.4a

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C3.3d describeneutralisationasacidreactingwithalkaliorabasetoformasaltpluswater

WS1.4a Productionofpuredrysampleofsalt.(PAGC4)

C3.3e recognisethataqueousneutralisationreactionscanbegeneralisedtohydrogenionsreactingwithhydroxideionstoformwater

WS1.4a

C3.3f recallthatcarbonatesandsomemetalsreactwithacidsandwritebalancedequationspredictingproductsfromgivenreactants

WS1.4a

C3.3g use and explain the terms dilute and concentrated (amount of substance) and weak and strong (degree of ionisation) in relation to acids

ratio of amount of acid to volume of solution

M1a,M1c,M1d

WS1.4a

C3.3h recallthatrelativeacidityandalkalinityaremeasuredbypH

WS1.4a

C3.3i describe neutrality and relative acidity and alkalinity in terms of the effect of the concentration of hydrogen ions on the numerical value of pH (whole numbers only)

pH of titration curves WS1.4a Neutralisationreactions.

C3.3j recall that as hydrogen ion concentration increases by a factor of ten the pH value of a solution decreases by a factor of one

M1a,M1c,M1d

WS1.4a

C3.3k describetechniquesandapparatususedtomeasurepH

DeterminingpHofunknownsolutions.

UseofpHprobes.

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C3.4 Electrolysis

SummaryDecompositionofaliquidduringtheconductionofelectricityisachemicalreactioncalledelectrolysis.Thissectionexplorestheelectrolysisofvariousmoltenionicliquidsandaqueousionicsolutions.

Underlying knowledge and understandingLearnersshouldbefamiliarwithionicsolutionsandsolids.

Common misconceptionsAcommonmisconceptionisthationicsolutionsconductbecauseofthemovementofelectrons.Anothercommonmisconceptionisthationicsolidsdonotconductelectricitybecauseelectronscannotmove.




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C3.4a recallthatmetals(orhydrogen)areformedatthecathodeandnon-metalsareformedattheanodeinelectrolysisusinginertelectrodes

thetermscationsandanions WS1.4a

C3.4b predicttheproductsofelectrolysisofbinaryioniccompoundsinthemoltenstate

compoundssuchasNaCl M1a,M1c WS1.2a,WS1.2b,WS1.2c,WS1.4a,WS2a,WS2b

C3.4c describecompetingreactionsintheelectrolysisofaqueoussolutionsofioniccompoundsintermsofthedifferentspeciespresent

theelectrolysisofaqueousNaClandCuSO4usinginertelectrodes

M1a,M1c WS1.4a Electrolysisofsodiumchloridesolution.(PAGC1)

Electrolysisofcoppersulfatesolution.(PAGC1)

C3.4d describeelectrolysisintermsoftheionspresentandreactionsattheelectrodes

M1a,M1c

C3.4e describethetechniqueofelectrolysisusinginertandnon-inertelectrodes

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Topic C4: Predicting and identifying chemical products

C4.1 Predicting chemical reactions

SummaryModelsofhowsubstancesreactandthedifferenttypesofchemicalreactionsthatcanoccurenableustopredictthelikelihoodandoutcomeofachemicalreaction.ThecurrentPeriodicTablewasdevelopedbasedonobservationsofthesimilaritiesanddifferencesinthepropertiesofelements.ThewaythatthePeriodicTableisarrangedintogroupsandperiodsrevealsthetrendsandpatternsinthebehaviouroftheelements.Themodelofatomicstructureprovidesanexplanationfortrendsandpatternsinthepropertiesofelements.Thearrangementofelementsingroupsandperiodsrevealstherelationshipbetweenobservablepropertiesandhowelectronsarearrangedintheatomsofeachelement.

Underlying knowledge and understandingLearnersshouldbefamiliarwiththeprinciplesunderpinningtheMendeleevPeriodicTable;thePeriodicTable:periodsandgroups;metalsandnon-metals;thevaryingphysicalandchemicalpropertiesofdifferentelements;thechemicalpropertiesofmetalsandnon-metals;thechemicalpropertiesofmetaland

non-metaloxideswithrespecttoacidityandhowpatternsinreactionscanbepredictedwithreferencetothePeriodicTable.

Common misconceptionsLearnersconsiderthepropertiesofparticlesofelementstobethesameasthebulkpropertiesofthatelement.Theytendtorelyonthecontinuousmattermodelratherthantheparticlemodel.Learnersconfusestatechangesanddissolvingwithchemicalchanges.Also,sincetheatmosphereisinvisibletotheeyeandlearnersrelyonconcrete,visibleinformation,thismeanslearnersoftenavoidtheroleofoxygenintheirexplanationsforopensystemreactions.Eveniftheroleofoxygenisappreciated,learnersdonotrealisethatsolidproductsofanoxidationreactionhavemoremassthanthestartingsolid.




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C4.1a recallthesimplepropertiesofGroups1,7and0

physicalandchemicalproperties WS1.2a,WS1.4aWS1.4c

Displacementreactionsofhalogenswithhalides.

C4.1b explainhowobservedsimplepropertiesofGroups1,7and0dependontheoutershellofelectronsoftheatomsandpredictpropertiesfromgiventrendsdownthegroups

easeofelectrongainorloss;physicalandchemicalproperties

C4.1c predictpossiblereactionsandprobablereactivityofelementsfromtheirpositionsinthePeriodicTable

WS1.1b,WS1.2a,WS1.4a

C4.1d explainhowthereactivityofmetalswithwaterordiluteacidsisrelatedtothetendencyofthemetaltoformitspositiveion

M1a,M1c WS1.4a Reactionofmetalswithwater,dilutehydrochloricacid.PAGC4,PAGC5)

C4.1e deduceanorderofreactivityofmetalsbasedonexperimentalresults

WS1.3e,WS2a Displacementreactionsinvolvingmetalsandmetalsalts.(PAGC4,PAGC5)

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Topic C5: Monitoring and controlling chemical reactions

C5.1 Controlling reactions

SummaryTherateandyieldofachemicalreactioncanbealteredbychangingthephysicalconditions.

Underlying knowledge and understandingLearnersshouldbefamiliarwiththeactionofcatalystsintermsofrateofreaction.Theyshouldknowthetermsurfaceareaandwhatitmeans.

Common misconceptionsLearnersoftenmisinterpretrategraphsandthinkthatcatalyststakepartinreactionsandrunout/getusedup.



CM5.1i arithmeticcomputation,ratiowhenmeasuringratesofreaction M1a,M1c

CM5.1ii drawingandinterpretingappropriategraphsfromdatatodeterminerateofreaction M4b,M4c

CM5.1iii determininggradientsofgraphsasameasureofrateofchangetodeterminerate M4d,M4e

CM5.1iv proportionalitywhencomparingfactorsaffectingrateofreaction M1c

Documents

OCR GCSE Combined Science A J250 Specification...as a starng point for lesson planning. Praccal suggesons (See topic CS7) Learning outcomes To include Maths (See appendix 5e) Working