171736 Specification Accredited a Level Gce Biology a h420

H420 For first assessment in 2017

BIOLOGY A

A LEVELSpecification

ocr.org.uk/alevelbiologya
http://www.ocr.org.uk/alevelbiologya

We will inform centres about any changes to the specification. We will also publish changes on our website. The latest version of our specification will always be the one on our website (ocr.org.uk) and this may differ from printed versions.

Copyright 2014 OCR. All rights reserved.

Copyright OCR retains the copyright on all its publications, including the specifications. However, registered centres for OCR are permitted to copy material from this specification booklet for their own internal use.

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Registered office: 1 Hills Road Cambridge CB1 2EU.

OCR is an exempt charity.
http://ocr.org.uk

OCR 2014A Level in Biology A i

Contents

Introducing A Level Biology A (from September 2015) iiTeaching and learning resources iiiProfessional development iv

1 Why choose an OCR A Level in Biology A? 11a. WhychooseanOCRqualification? 11b. WhychooseanOCRALevelinBiologyA? 21c. Whatarethekeyfeaturesofthisspecification? 31d. HowdoIfindoutmoreinformation? 4

2 Thespecificationoverview 52a. Overview of A Level in Biology A (H420) 52b. Content of A Level in Biology A (H420) 62c. Content of modules 1 to 6 82d. Prior knowledge, learning and progression 51

3 Assessment of OCR A Level in Biology A 523a. Forms of assessment 523b. Assessmentobjectives(AO) 533c. Assessment availability 533d. Retakingthequalification 543e. Assessment of extended responses 543f. Synopticassessment 543g. Calculatingqualificationresults 54

4 Admin:whatyouneedtoknow 554a. Pre-assessment 554b. Accessibilityandspecialconsideration 564c. External assessment arrangements 564d. Non exam assessment 564e. Resultsandcertificates 564f. Post-results services 574g. Malpractice 57

5 Appendices 585a. Grade descriptors 585b. Overlapwithotherqualifications 585c. Avoidance of bias 585d. How Science Works (HSW) 595e. Mathematicalrequirements 605f. Health and Safety 685g. Practicalendorsement 69

OCR 2014A Level in Biology Aii

Introducing ALevelBiologyA(fromSeptember2015)Thisspecificationallowsteacherstoadoptaflexibleapproach to the delivery of A Level Biology. The course has been designed to enable centres to deliver the content modules (Modules 26) using the framework provided,ortodesignacustomisedcourse.Practicalwork undertaken to support teaching of the content willservetocovertherequirementsofthepracticalskills module (Module 1), which is assessed in the writtenexaminationsandthroughthePracticalEndorsement.

Thespecificationisdividedintotopics,eachcontainingdifferentkeyconceptsofbiology.Throughoutthespecification,cross-referencesindicatetherelevanceofindividuallearningoutcomestothemathematicalandpracticalcriteriathatareembeddedintheassessments.

ThisspecificationincorporatestheOfqualGCESubjectLevelConditionsandRequirementsforBiology.

Meet the team

We have a dedicated team of people working on our A LevelBiologyqualifications.

Find out more about our Biology team at ocr.org.uk/scienceteam

If you need specialist advice, guidance or support, get in touch as follows:

01223 553998

[email protected]

@OCR_science
http://www.ocr.org.uk/qualifications/by-subject/science/meet-the-team/http://www.ocr.org.uk/qualifications/by-subject/science/meet-the-team/https://twitter.com/ocr_science

OCR 2014A Level in Biology A iii

Teachingandlearningresources

Werecognisethattheintroductionofanewspecificationcanbringchallengesforimplementationand teaching. Our aim is to help you at every stage and wereworkinghardtoprovideapracticalpackageofsupportincloseconsultationwithteachersandotherexperts, so we can help you to make the change.

Designedtosupportprogressionforall

Our resources are designed to provide you with a rangeofteachingactivitiesandsuggestionssoyoucanselectthebestapproachforyourparticularstudents.You are the experts on how your students learn and our aim is to support you in the best way we can.

Wewantto

Support you with a body of knowledge thatgrowsthroughoutthelifetimeofthespecification

Provideyouwitharangeofsuggestionssoyoucanselectthebestactivity,approachorcontextforyourparticularstudents.

Make it easier for you to explore and interact with our resource materials, in particulartodevelopyourownschemesof work.

Createanongoingconversationsowecandevelop materials that work for you.

Plentyofusefulresources

Youllhavefourmaintypesofsubject-specificteachingandlearningresourcesatyourfingertips:

Delivery Guides

TransitionGuides

TopicExplorationPacks

Lesson elements.

Alongwithsubject-specificresources,youllalsohaveaccesstoaselectionofgenericresourcesthatfocuson skills development and professional guidance for teachers.

SkillsGuides weve produced a set of Skills Guides thatarenotspecifictoBiology,buteachcoversatopicthatcouldberelevanttoarangeofqualificationsforexample,communication,legislationandresearch.Download the guides at ocr.org.uk/skillsguides

ActiveResults a free online results analysis service to help you review the performance of individual students or your whole school. It provides access to detailed results data, enabling more comprehensive analysis of results in order to give you a more accurate measurement of the achievements of your centre and individual students. For more details refer to ocr.org.uk/activeresults
http://ocr.org.uk/i-want-to/skills-guides/http://ocr.org.uk/ocr-for/teachers/active-results/http://ocr.org.uk/ocr-for/teachers/active-results/

OCR 2014A Level in Biology Aiv

Professionaldevelopment

Take advantage of our improved Professional Development Programme, designed with you in mind. Whether you want to come to face-to-face events, look at our new digital training or search for training materials,youcanfindwhatyourelookingforallinone place at the CPD Hub.

Anintroductiontothenewspecifications:

Well be running events to help you get to grips with ourALevelBiologyAqualification.

These events are designed tohelpprepareyouforfirstteaching and to support your delivery at every stage.

Watch out for details at cpdhub.ocr.org.uk

Toreceivethelatestinformationaboutthetrainingwellbeoffering,pleaseregisterfor A Level email updates at ocr.org.uk/updates
https://www.cpdhub.ocr.org.uk/desktopdefault.aspxhttp://ocr.org.uk/i-want-to/email-updates/

OCR 2014A Level in Biology A 1

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1 Why choose an OCR A Level in Biology A?

1a. WhychooseanOCRqualification?

Choose OCR and youve got the reassurance that youre working with one of the UKs leading exam boards. Our new A Level in Biology A course has been developedinconsultationwithteachers,employersandhighereducationtoprovidestudentswithaqualificationthatsrelevanttothemandmeetstheirneeds.

Were part of the Cambridge Assessment Group, Europes largest assessment agency and a department of the University of Cambridge. Cambridge Assessment plays a leading role in developing and delivering assessmentsthroughouttheworld,operatinginover150 countries.

Weworkwitharangeofeducationproviders,includingschools,colleges,workplacesandotherinstitutionsin both the public and private sectors. Over 13,000 centreschooseourAlevels,GCSEsandvocationalqualificationsincludingCambridgeNationals,Cambridge Technicals and Cambridge Progression.

OurSpecifications

Webelieveindevelopingspecificationsthathelpyoubring the subject to life and inspire your students to achieve more.

Wevecreatedteacher-friendlyspecificationsbasedonextensive research and engagement with the teaching community.Theyredesignedtobestraightforwardand accessible so that you can tailor the delivery of the course to suit your needs. We aim to encourage learners to become responsible for their own learning, confidentindiscussingideas,innovativeandengaged.

We provide a range of support services designed to helpyouateverystage,frompreparationthroughtothedeliveryofourspecifications.Thisincludes:

Awiderangeofhigh-qualitycreativeresourcesincluding:o delivery guideso transitionguideso topicexplorationpackso lesson elementso and much more.

Access to Subject Specialists to support you throughthetransitionandthroughoutthelifetimeofthespecifications.

CPD/Training for teachers including face-to-faceeventstointroducethequalificationsandprepareyouforfirstteaching.

ActiveResultsourfreeresultsanalysisserviceto help you review the performance of individual students or whole schools.

ExamCreator our new online past papers service that enables you to build your own test papersfrompastOCRexamquestions.

AllAlevelqualificationsofferedbyOCRareaccreditedbyOfqual,theRegulatorforqualificationsofferedinEngland.TheaccreditationnumberforOCRsALevelinBiology A is (601/4260/1)

OCR 2014A Level in Biology A2

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1b. WhychooseanOCRALevelinBiologyA?

Weappreciatethatonesizedoesntfitallsoweoffertwosuitesofqualificationsineachscience:

Biology AProvidesaflexibleapproachtoteaching.Thespecificationisdividedintotopics,eachcoveringdifferentkeyconceptsofbiology.Teachingofpracticalskillsisintegratedwiththetheoreticaltopicsandtheyareassessedthroughthewrittenpapers.ForAlevelonly,thePracticalEndorsementwillalsosupportthedevelopmentofpracticalskills.

BiologyB(AdvancingBiology)(anewcourseforOCR) Learners study biology using a context-based approach. Ideas are introduced within relevant and interestingsettingswhichhelplearnerstoanchortheirconceptual knowledge of the range of biological topics requiredatGCElevel.Practicalskillsareembeddedwithinthespecificationandlearnersareexpectedtocarryoutpracticalworkinpreparationforawrittenexaminationthatwillspecificallytesttheseskills.

Allofourspecificationshavebeendevelopedwithsubject and teaching experts. We have worked in close consultationwithteachersandrepresentativesfromHigherEducation(HE)withtheaimofincludingup-to-date relevant content within a framework that is

interestingtoteachandadministerwithinallcentres(large and small).

OurnewALevelinBiologyAqualificationbuildsonourexistingpopularcourse.Wevebasedtheredevelopment of our A level sciences on an understanding of what works well in centres large and small and have updated areas of content and assessmentwherestakeholdershaveidentifiedthatimprovements could be made. Weve undertaken a significantamountofconsultationthroughourscienceforums(whichincluderepresentativesfromlearnedsocieties,HE,teachingandindustry)andthroughfocusgroupswithteachers.Ourpapersandspecificationshave been trialled in centres during development to make sure they work well for all centres and learners.

Thecontentchangesareanevolutionofourlegacyofferingandwillbefamiliartocentresalreadyfollowing our courses, but are also clear and logically laid out for centres new to OCR, with assessment modelsthatarestraightforwardtoadminister.WehaveworkedcloselywithteachersandHErepresentativesto provide high quality support materials to guide you throughthenewqualifications.

Aimsandlearningoutcomes

OCRsALevelinBiologyAspecificationaimstoencourage learners to:

developessentialknowledgeandunderstandingofdifferentareasofthesubjectandhowtheyrelate to each other

developanddemonstrateadeepappreciationof the skills, knowledge and understanding of scientificmethods

developcompetenceandconfidenceinavarietyofpractical,mathematicalandproblemsolvingskills

develop their interest in and enthusiasm for the subject, including developing an interest in further study and careers associated with the subject

understand how society makes decisions about scientificissuesandhowthesciencescontributeto the success of the economy and society (as exemplifiedinHowScienceWorks(HSW)).


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1c. Whatarethekeyfeaturesofthisspecification?

OurALevelinBiologyAspecificationisdesignedwithacontent-ledapproachandprovidesaflexiblewayofteaching.Thespecification:

retains and refreshes the popular topics from thelegacyOCRBiologyqualification(H421)

is laid out clearly in a series of teaching modules withadditionalguidanceaddedwhererequiredto clarify assessment requirements

is co-teachable with the AS level

embedspracticalrequirementswithintheteaching modules

identifiesPracticalEndorsementrequirementsand how these can be integrated into teaching ofcontent(seeSection5g)

exemplifiesthemathematicalrequirementsofthecourse(seeSection5e)

highlightsopportunitiesfortheintroductionofkeymathematicalrequirements(seeSection5eandtheadditionalguidancecolumnforeachmodule) into your teaching

identifies,withintheAdditionalguidancecolumn how the skills, knowledge and understanding of How Science Works (HSW) can be incorporated within teaching.

Teachersupport

Theextensivesupportofferedalongsidethisspecificationincludes:

deliveryguidesprovidinginformationonassessed content, the associated conceptual development and contextual approaches to delivery

transitionguidesidentifyingthelevelsofdemandandprogressionfordifferentkeystagesforaparticulartopicandgoingontoprovidelinkstohighqualityresourcesandcheckpointtaskstoassistteachersinidentifyinglearnersreadyforprogression

lessonelementswrittenbyexperts,providingallthematerialsnecessarytodelivercreativeclassroomactivities

ActiveResults(seeSection1a)

ExamCreator(seeSection1a)

mockexaminationsservice a free service offeringapracticequestionpaperandmarkscheme(downloadablefromasecurelocation).

Along with:

Subject Specialists within the OCR science team to help with course queries

teacher training

Science Spotlight(ourtermlynewsletter)

OCR Science community

aconsultancyservice(toadviseonPracticalEndorsement requirements)

PracticalSkillsHandbook

Maths Skills Handbook.


1d. HowdoIfindoutmoreinformation?

Whethernewtoourspecifications,orcontinuingonfromourlegacyofferings,youcanfindmoreinformationonourwebpagesat:www.ocr.org.uk

Visitoursubjectpagestofindoutmoreabouttheassessment package and resources available to support your teaching. The science team also release a termly newsletterScience Spotlight (despatched to centres and available from our subject pages).

You can contact the Science Subject Specialists: [email protected], 01223 553998

Join our Science community: http://social.ocr.org.uk/

Check what CPD events are available: www.cpdhub.ocr.org.uk

FollowusonTwitter:@ocr_science

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http://www.ocr.org.ukhttp://social.ocr.org.uk/groups/sciencehttps://www.cpdhub.ocr.org.uk/desktopdefault.aspxhttps://twitter.com/ocr_science


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2 Thespecificationoverview

2a. OverviewofALevelinBiologyA(H420)

Learners must complete all components (01, 02, 03 and 04).

ContentOverview AssessmentOverview

Content is split into six teaching modules:

Module 1 Development of practicalskillsinbiology

Module2Foundationsinbiology

Module 3 Exchange and transport

Module 4 Biodiversity, evolutionanddisease

Module5Communication,homeostasis and energy

Module6Genetics,evolutionandecosystems

Component 01 assesses content from modules 1, 2, 3 and 5.

Component 02 assesses content from modules 1, 2, 4 and 6.

Component 03 assesses content from all modules (1 to 6).

Biological processes

(01)

100 marks

2 hour 15 minutes writtenpaper

37%

of total A level

Biological diversity

(02)

100 marks


37%

of total A level

Unifiedbiology

(03)

70 marks


26%

of total A level

Practicalendorsement in biology

(04)*

(non exam assessment)

Reported separately

(see section5g)

*DetailstobeconfirmedbyOfqual.

Allcomponentsincludesynopticassessment.


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2b. ContentofALevelinBiologyA(H420)

TheALevelinBiologyAspecificationcontentisdividedinto six teaching modules and each module is further divided into key topics. Each module is introduced with a summary of the biology it contains and each topic is also introduced with a short summary text. The assessable content is divided into two columns: Learningoutcomesand Additionalguidance.

The Learning outcomes may all be assessed in the examinations(withtheexceptionofsomeoftheskillsinsection1.2 which will be assessed directly through thePracticalEndorsement).TheAdditionalguidancecolumn is included to provide further advice on delivery and the expected skills required from learners.

ReferencestoHSW(Section5d)areincludedintheguidancetohighlightopportunitiestoencourageawider understanding of science.

Themathematicalrequirementsinsection5e,arealsoreferencedbytheprefixMtolinkthemathematicalskills required for A Level Biology to examples of biologycontentwherethosemathematicalskillscouldbe linked to learning.

Thespecificationhasbeendesignedtobeco-teachablewiththestandaloneASLevelinBiologyAqualification.ThefirstfourmodulescomprisetheASLevelinBiologyAcourseandlearnersstudyingtheAlevelcontinuewith the content of modules 5 and 6. The internally assessedPracticalEndorsementskillsalsoformpartofthe full A level (see module 1.2).

A summary of the content for the A level course is as follows:

Module1Developmentofpracticalskillsinbiology

1.1 Practicalskillsassessedinawrittenexamination

1.2 Practicalskillsassessedinthepracticalendorsement

Module2Foundationsinbiology

2.1.1 Cell structure

2.1.2 Biological molecules

2.1.3 Nucleotidesandnucleicacids

2.1.4 Enzymes

2.1.5 Biological membranes

2.1.6 Cell division, cell diversity and cellular organisation

Module3Exchangeandtransport

3.1.1 Exchange surfaces

3.1.2 Transport in animals

3.1.3 Transport in plants

Module4Biodiversity,evolutionanddisease

4.1.1 Communicablediseases,diseasepreventionandthe immune system

4.2.1 Biodiversity

4.2.2 Classificationandevolution

Module5Communication,homeostasisandenergy

5.1.1 Communicationandhomeostasis

5.1.2 Excretionasanexampleofhomeostaticcontrol

5.1.3 Neuronalcommunication

5.1.4 Hormonalcommunication

5.1.5 Plant and animal responses

5.2.1 Photosynthesis

5.2.2 Respiration

Module6Genetics,evolutionandecosystems

6.1.1 Cellular control

6.1.2 Patternsofinheritance

6.1.3 Manipulatinggenomes

6.2.1 Cloning and biotechnology

6.3.1 Ecosystems

6.3.2 Populationsandsustainability.


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Assessmentofpracticalskillsandthepracticalendorsement

Module1ofthespecificationcontentrelatestothepracticalskillslearnersareexpectedtogainthroughoutthe course, which are assessed throughout the writtenexaminationsandalsothroughthePracticalEndorsement(seeSection5g).

PracticalactivitiesareembeddedwithinthelearningoutcomesofthecoursetoencouragepracticalactivitiesintheclassroomwhichcontributetotheachievementofthePracticalEndorsement(Section5g)

as well as enhancing learners understanding of biologicaltheoryandpracticalskills.

OpportunitiesforcarryingoutactivitiesthatcouldcounttowardsthePracticalEndorsementareindicatedthroughoutthespecification.TheseareshownintheAdditionalguidancecolumnasPAG1 to PAG11 (PracticalActivityGroup,seeSection5g).ThereareawidevarietyofopportunitiestoassessPAG12 throughoutthequalification.


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2c. Contentofmodules1to6

Module1:Developmentofpracticalskillsinbiology

Thedevelopmentofpracticalskillsisafundamentalandintegralaspectofthestudyofanyscientificsubject. These skills not only enhance learners

understanding of the subject but also serve as a suitablepreparationforthedemandsofstudyingbiology at a higher level.

1.1Practicalskillsassessedinawrittenexamination

Practicalskillsareembeddedthroughoutallthecontentofthisspecification.

Learners will be required to develop a range of practicalskillsthroughouttheircourseinpreparationforthewrittenexaminations.

1.1.1Planning

Learningoutcomes Additionalguidance

Learners should be able to demonstrate and apply their knowledge and understanding of:

(a) experimental design, including to solve problems setinapracticalcontext

Includingselectionofsuitableapparatus,equipmentand techniques for the proposed experiment.

Learnersshouldbeabletoapplyscientificknowledgebasedonthecontentofthespecificationtothepracticalcontext. HSW3

(b) identificationofvariablesthatmustbecontrolled, where appropriate

(c) evaluationthatanexperimentalmethodisappropriate to meet the expected outcomes.

HSW6

1.1.2Implementing



(a) howtouseawiderangeofpracticalapparatusand techniques correctly

AsoutlinedinthecontentofthespecificationandtheskillsrequiredforthePracticalEndorsement. HSW4

(b) appropriate units for measurements M0.1

(c) presentingobservationsanddatainanappropriate format.

HSW8


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1.1.3Analysis



(a) processing,analysingandinterpretingqualitativeandquantitativeexperimentalresults

Including reaching valid conclusions, where appropriate. HSW5

(b) useofappropriatemathematicalskillsforanalysisofquantitativedata

RefertoSection5eforalistofmathematicalskillsthat learners should have acquired competence in as part of their course.HSW3

(c) appropriateuseofsignificantfigures M1.1

(d) plottingandinterpretingsuitablegraphsfromexperimental results, including:

(i) selectionandlabellingofaxeswithappropriatescales,quantitiesandunits

(ii) measurement of gradients and intercepts.

M3.2

M3.3, M3.4, M3.5

1.1.4Evaluation



(a) how to evaluate results and draw conclusions HSW6

(b) theidentificationofanomaliesinexperimentalmeasurements

(c) thelimitationsinexperimentalprocedures

(d) precision and accuracy of measurements and data, including margins of error, percentage errorsanduncertaintiesinapparatus

M1.11

(e) therefiningofexperimentaldesignbysuggestionof improvements to the procedures and apparatus.

HSW3

1.2Practicalskillsassessedinthepracticalendorsement

Arangeofpracticalexperiencesisavitalpartofalearners development as part of this course.

LearnersshoulddevelopandpractiseawiderangeofpracticalskillsthroughoutthecourseaspreparationforthePracticalEndorsement,aswellasforthewrittenexaminations.

TheexperimentsandskillsrequiredforthePracticalEndorsement will allow learners to develop and

practisetheirpracticalskills,preparinglearnersforthewrittenexaminations.

PleaserefertoSection5g(thePracticalEndorsement)inthisspecificationtoseethelistofpracticalexperiences all learners should cover during their course.FurtheradviceandguidanceonthePracticalEndorsementcanbefoundinthePracticalSkillsHandbook.


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1.2.1Practicalskills


Practical work carried out throughout the course will enable learners to develop the following skills:

Independentthinking

(a) applyinvestigativeapproachesandmethodstopracticalwork

Includinghowtosolveproblemsinapracticalcontext. HSW3

Useandapplicationofscientificmethodsandpractices

(b) safelyandcorrectlyusearangeofpracticalequipment and materials

SeeSection5g.

Includingidentificationofpotentialhazards.Learners should understand how to minimise the risks involved. HSW4

(c) followwritteninstructions

(d) makeandrecordobservations/measurements HSW8

(e) keep appropriate records of experimental activities

SeeSection5g.

(f) presentinformationanddatainascientificway HSW8

(g) useappropriatesoftwareandtoolstoprocessdata,carryoutresearchandreportfindings

M3.1 HSW3

Researchandreferencing

(h) useonlineandofflineresearchskillsincludingwebsites,textbooksandotherprintedscientificsourcesofinformation

(i) correctlycitesourcesofinformation ThePracticalSkillsHandbookprovidesguidanceonappropriatemethodsforcitinginformation.

Instrumentsandequipment

(j) useawiderangeofexperimentalandpracticalinstruments, equipment and techniques appropriate to the knowledge and understanding includedinthespecification.

SeeSection5g.

HSW4


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1.2.2Useofapparatusandtechniques


Through use of the apparatus and techniques listed below, and a minimum of 12 assessed practicals (see Section 5g), learners should be able to demonstrate all of the practical skills listed within 1.2.1 and CPAC (Section 5g, Table 2) as exemplified through:

(a) use of appropriate apparatus to record a range ofquantitativemeasurements(toincludemass,time,volume,temperature,lengthandpH)

HSW4

(b) useofappropriateinstrumentationtorecordquantitativemeasurements,suchasacolorimeter or potometer

HSW4

(c) use of laboratory glassware apparatus for a variety of experimental techniques to include serialdilutions

HSW4

(d) use of a light microscope at high power and low power,includinguseofagraticule

HSW4

(e) productionofscientificdrawingsfromobservationswithannotations

HSW8

(f) useofqualitativereagentstoidentifybiologicalmolecules

HSW4

(g) separationofbiologicalcompoundsusingthinlayer/paper chromatography or electrophoresis

HSW4

(h) safe and ethical use of organisms to measure:

(i) plant or animal responses(ii) physiologicalfunctions

HSW4, HSW10

(i) useofmicrobiologicalaseptictechniques,including the use of agar plates and broth

HSW4

(j) safeuseofinstrumentsfordissectionofananimal or plant organ

HSW4

(k) useofsamplingtechniquesinfieldwork HSW4

(l) use of ICT such as computer modelling, or a dataloggertocollectdata,oruseofsoftwaretoprocess data.

HSW3, HSW4


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Module2:Foundationsinbiology

Alllivingorganismshavesimilaritiesincellularstructure,biochemistryandfunction.Anunderstandingofthesesimilaritiesisfundamentaltothe study of the subject.

This module gives learners the opportunity to use microscopy to study the cell structure of a variety of organisms. Biologically important molecules such as carbohydrates, proteins, water and nucleic acids are studiedwithrespecttotheirstructureandfunction.Thestructureandmodeofactionofenzymesincatalysingbiochemicalreactionsisstudied.

Membranes form barriers within, and at the surface of, cells. This module also considers the way in which thestructureofmembranesrelatestothedifferentmethods by which molecules enter and leave cells and organelles.

Thedivisionandsubsequentspecialisationofcellsisstudied,togetherwiththepotentialforthetherapeuticuse of stem cells.

Learners are expected to apply knowledge, understanding and other skills developed in this moduletonewsituationsand/ortosolverelatedproblems.

2.1Foundationsinbiology

2.1.1Cellstructure

Biology is the study of living organisms. Every living organism is made up of one or more cells, therefore understandingthestructureandfunctionofthecellisa fundamental concept in the study of biology. Since RobertHookecoinedthephrasecellsin1665,careful

observationusingmicroscopeshasrevealeddetailsofcell structure and ultrastructure and provided evidence to support hypotheses regarding the roles of cells and their organelles.



(a) theuseofmicroscopytoobserveandinvestigatedifferenttypesofcellandcellstructureinarangeofeukaryoticorganisms

Toincludeanappreciationoftheimagesproducedby a range of microscopes, light microscope, transmission electron microscope, scanning electron microscope and laser scanning confocal microscope.

HSW1, HSW7

(b) thepreparationandexaminationofmicroscopeslides for use in light microscopy

Includingtheuseofaneyepiecegraticuleandstagemicrometer. PAG1 HSW4

(c) the use of staining in light microscopy Toincludetheuseofdifferentialstainingtoidentifydifferentcellularcomponentsandcelltypes. PAG1 HSW4, HSW5

(d) therepresentationofcellstructureasseenunder the light microscope using drawings and annotated diagrams of whole cells or cells in sectionsoftissue

PAG1


2

(e) theuseandmanipulationofthemagnificationformula

magnification = image size object size

M0.1, M0.2, M0.3, M1.1, M1.8, M2.2, M2.3, M2.4

(f) thedifferencebetweenmagnificationandresolution

Toincludeanappreciationofthedifferencesinresolutionandmagnificationthatcanbeachievedby a light microscope, a transmission electron microscope and a scanning electron microscope.

M0.2, M0.3 HSW7, HSW8

(g) theultrastructureofeukaryoticcellsandthefunctionsofthedifferentcellularcomponents

To include the following cellular components and anoutlineoftheirfunctions:nucleus,nucleolus,nuclear envelope, rough and smooth endoplasmic reticulum(ER),Golgiapparatus,ribosomes,mitochondria, lysosomes, chloroplasts, plasma membrane,centrioles,cellwall,flagellaandcilia.

M0.2

(h) photomicrographs of cellular components in a rangeofeukaryoticcells

Toincludeinterpretationoftransmissionandscanning electron microscope images.

(i) theinterrelationshipbetweentheorganellesinvolvedintheproductionandsecretionofproteins

No detail of protein synthesis is required.

(j) the importance of the cytoskeleton To include providing mechanical strength to cells, aiding transport within cells and enabling cell movement.

HSW2

(k) thesimilaritiesanddifferencesinthestructureandultrastructureofprokaryoticandeukaryoticcells.

PAG1


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2.1.2Biologicalmolecules

The cells of all living organisms are composed of biological molecules. Proteins, carbohydrates and lipids are three of the key groups of biological

macromoleculesthatareessentialforlife.Astudyofthestructureofthesemacromoleculesallowsabetterunderstandingoftheirfunctionsinlivingorganisms.



Whereappropriate,thissectionshouldincludediagrams to represent molecular structure and bonding.

(a) how hydrogen bonding occurs between water molecules,andrelatethis,andotherpropertiesof water, to the roles of water for living organisms

Arangeofrolesthatrelatetothepropertiesofwater, including solvent, transport medium, coolant and as a habitat AND roles illustrated using examples of prokaryotes and eukaryotes.

HSW2, HSW8

(b) the concept of monomers and polymers and theimportanceofcondensationandhydrolysisreactionsinarangeofbiologicalmolecules

(c) the chemical elements that make up biological molecules

To include:

C, H and O for carbohydrates C, H and O for lipids C, H, O, N and S for proteins C, H, O, N and P for nucleic acids

(d) theringstructureandpropertiesofglucoseasan example of a hexose monosaccharide and the structure of ribose as an example of a pentose monosaccharide

Toincludethestructuraldifferencebetweenan -anda-glucosemolecule AND thedifferencebetweenahexoseandapentosemonosaccharide.

(e) the synthesis and breakdown of a disaccharide andpolysaccharidebytheformationandbreakage of glycosidic bonds

To include the disaccharides sucrose, lactose and maltose.

(f) the structure of starch (amylose and amylopectin),glycogenandcellulosemolecules

HSW8

(g) howthestructuresandpropertiesofglucose,starch, glycogen and cellulose molecules relate to theirfunctionsinlivingorganisms

HSW2, HSW8

(h) the structure of a triglyceride and a phospholipid as examples of macromolecules

To include an outline of saturated and unsaturated fattyacids.

(i) the synthesis and breakdown of triglycerides by theformation(esterification)andbreakageofesterbondsbetweenfattyacidsandglycerol


2

(j) howthepropertiesoftriglyceride,phospholipidand cholesterol molecules relate to their functionsinlivingorganisms

To include hydrophobic and hydrophilic regions and energy content AND illustrated using examples of prokaryotes and eukaryotes.

HSW2, HSW8

(k) the general structure of an amino acid

(l) thesynthesisandbreakdownofdipeptidesandpolypeptides,bytheformationandbreakageofpeptidebonds

(m) the levels of protein structure Toincludeprimary,secondary,tertiaryandquaternary structure AND hydrogen bonding, hydrophobic and hydrophilic interactions,disulfidebondsandionicbonds.

HSW8

(n) thestructureandfunctionofglobularproteinsincluding a conjugated protein

To include haemoglobin as an example of a conjugated protein (globular protein with a prostheticgroup),anamedenzymeandinsulin.

An opportunity to use computer modelling to investigatethelevelsofproteinstructurewithinthemolecule. PAG10

(o) thepropertiesandfunctionsoffibrousproteins Toincludecollagen,keratinandelastin(nodetailsofstructure are required).

(p) the key inorganic ions that are involved in biological processes

To include the correct chemical symbols for the followingcationsandanions:

cations:calciumions(Ca2+), sodium ions (Na+), potassium ions (K+), hydrogen ions (H+), ammonium ions (NH4

+)

anions: nitrate (NO3), hydrogencarbonate (HCO3

), chloride (Cl ), phosphate (PO4

3), hydroxide, (OH).

(q) how to carry out and interpret the results of the following chemical tests:

biuret test for proteins

Benedicts test for reducing and non-reducing sugars

reagent test strips for reducing sugars

iodine test for starch

emulsion test for lipids

PAG9 HSW3, HSW4, HSW5


2

(r) quantitativemethodstodeterminetheconcentrationofachemicalsubstanceinasolution

To include colorimetry and the use of biosensors (an outline only of the mechanism is required). PAG5 HSW3, HSW4, HSW5

(s) (i) the principles and uses of paper and thin layer chromatography to separate biological molecules / compounds

(ii) practicalinvestigationstoanalysebiologicalsolutionsusingpaperorthinlayerchromatography.

Toincludecalculationofretention(Rf) values.

Forexampletheseparationofproteins,carbohydrates, vitamins or nucleic acids.

M0.1, M0.2, M1.1, M1.3, M2.2, M2.3, M2.4 PAG6 HSW2, HSW3, HSW4


2

2.1.3Nucleotidesandnucleicacids

Nucleicacidsareessentialtoheredityinlivingorganisms.Understandingthestructureofnucleotidesand nucleic acids allows an understanding of their roles

inthestorageanduseofgeneticinformationandcellmetabolism.



(a) thestructureofanucleotideasthemonomerfrom which nucleic acids are made

ToincludethedifferencesbetweenRNAandDNAnucleotides,theidentificationofthepurinesandpyrimidines and the type of pentose sugar.

An opportunity to use computer modelling to investigatenucleicacidstructure. PAG10

(b) thesynthesisandbreakdownofpolynucleotidesbytheformationandbreakageofphosphodiesterbonds

(c) the structure of ADP and ATP as phosphorylated nucleotides

Comprising a pentose sugar (ribose), a nitrogenous base (adenine) and inorganic phosphates.

(d) (i) the structure of DNA (deoxyribonucleic acid)(ii) practicalinvestigationsintothepurification

ofDNAbyprecipitation

To include how hydrogen bonding between complementary base pairs (A to T, G to C) on two antiparallelDNApolynucleotidesleadstotheformationofaDNAmolecule,andhowthetwistingofDNAproducesitsdouble-helixshape. PAG9 HSW3, HSW4

(e) semi-conservativeDNAreplication To include the roles of the enzymes helicase and DNApolymerase,theimportanceofreplicationinconservinggeneticinformationwithaccuracyandtheoccurrenceofrandom,spontaneousmutations.

HSW8

(f) thenatureofthegeneticcode To include the triplet, non-overlapping, degenerate and universal nature of the code and how a gene determines the sequence of amino acids in a polypeptide(theprimarystructureofaprotein).

(g) transcriptionandtranslationofgenesresultinginthesynthesisofpolypeptides.

To include, the roles of RNA polymerase, messenger (m)RNA, transfer (t)RNA, ribosomal (r)RNA.

HSW8


2

2.1.4Enzymes

Metabolism in living organisms relies upon enzyme-controlledreactions.Knowledgeofhowenzymesfunctionandthefactorsthataffectenzymeactionhas

improved our understanding of biological processes and increased our use of enzymes in industry.



(a) theroleofenzymesincatalysingreactionsthataffectmetabolismatacellularandwholeorganism level

Toincludetheideathatenzymesaffectbothstructureandfunction.

(b) the role of enzymes in catalysing both intracellularandextracellularreactions

To include catalase as an example of an enzyme thatcatalysesintracellularreactionsandamylaseand trypsin as examples of enzymes that catalyse extracellularreactions.

(c) themechanismofenzymeaction Toincludethetertiarystructure,specificity,activesite,lockandkeyhypothesis,induced-fithypothesis, enzyme-substrate complex, enzyme-productcomplex,productformationandloweringofactivationenergy.

HSW1, HSW8

(d) (i) theeffectsofpH,temperature,enzymeconcentrationandsubstrateconcentrationonenzymeactivity

(ii) practicalinvestigationsintotheeffectsofpH,temperature,enzymeconcentrationandsubstrateconcentrationonenzymeactivity

Toincludereferencetothetemperaturecoefficient(Q10).

Anopportunityforserialdilutions. M0.1, M0.2, M0.3, M1.1, M1.3, M1.11, M3.1, M3.2, M3.3, M3.5, M3.6 PAG4 HSW1, HSW2, HSW4, HSW5, HSW6, HSW8.

(e) theneedforcoenzymes,cofactorsandprostheticgroupsinsomeenzyme-controlledreactions

To include Cl as a cofactor for amylase, Zn2+ as aprostheticgroupforcarbonicanhydraseandvitamins as a source of coenzymes. PAG4

(f) theeffectsofinhibitorsontherateofenzyme-controlledreactions.

Toincludecompetitiveandnon-competitiveandreversible and non-reversible inhibitors with referencetotheactionofmetabolic poisons and some medicinal drugs, and the role of product inhibition AND inactiveprecursorsinmetabolicpathways(coveredat A level only).

M0.1, M0.2, M0.3, M1.1, M1.3, M1.11, M3.1, M3.2, M3.3, M3.5, M3.6 PAG4 HSW1, HSW2, HSW4, HSW5, HSW6, HSW8


2

2.1.5Biologicalmembranes

Membranes are fundamental to the cell theory. The structure of the plasma membrane allows cells to communicate with each other. Understanding this abilitytocommunicateisimportantasscientistsincreasingly make use of membrane-bound receptors assitesfortheactionofmedicinaldrugs.

Understandinghowdifferentsubstancesentercellsisalso crucial to the development of mechanisms for the administrationofdrugs.



(a) the roles of membranes within cells and at the surface of cells

To include the roles of membranes as,

partiallypermeablebarriersbetweenthecelland its environment, between organelles and the cytoplasm and within organelles

sitesofchemicalreactions

sitesofcellcommunication(cellsignalling).

(b) thefluidmosaicmodelofmembranestructureand the roles of its components

To include phospholipids, cholesterol, glycolipids, proteins and glycoproteins AND the role of membrane-bound receptors as sites where hormones and drugs can bind.

M0.2 HSW1

(c) (i) factorsaffectingmembranestructureandpermeability

(ii) practicalinvestigationsintofactorsaffectingmembrane structure and permeability

Toincludetheeffectsoftemperatureandsolvents.

M0.1, M0.2, M1.1, M1.2, M1.3, M1.6, M1.11, M3.1, M3.2, M3.3, M3.5, M3.6 PAG8 HSW1, HSW2, HSW3, HSW4, HSW5, HSW6

(d) (i) the movement of molecules across membranes

(ii) practicalinvestigationsintothefactorsaffectingdiffusionratesinmodelcells

Toincludediffusionandfacilitateddiffusionaspassive methods AND activetransport,endocytosisandexocytosisasprocesses requiring adenosine triphosphate (ATP) as an immediate source of energy.

M0.1, M0.2, M0.3, M1.1, M1.2, M1.3, M1.6, M1.11, M2.1, M3.1, M3.2, M3.3, M3.5, M3.6, M4.1 PAG8 HSW1, HSW2, HSW3, HSW4, HSW5, HSW6


2

(e) (i) the movement of water across membranes byosmosisandtheeffectsthatsolutionsofdifferentwaterpotentialcanhaveonplantand animal cells

(ii) practicalinvestigationsintotheeffectsofsolutionsofdifferentwaterpotentialonplant and animal cells.

Osmosis to be explained in terms of a water potentialgradientacrossapartially-permeablemembrane.

M0.1, M0.2, M0.3, M1.1, M1.2, M1.3, M1.6, M1.10, M1.11, M2.1, M3.1, M3.2, M4.1 PAG8 HSW1, HSW2, HSW3, HSW4, HSW5, HSW6

2.1.6Celldivision,celldiversityandcellularorganisation

Duringthecellcycle,geneticinformationiscopiedandpassed to daughter cells. Microscopes can be used to viewthedifferentstagesofthecycle.

Inmulticellularorganisms,stemcellsaremodifiedtoproducemanydifferenttypesofspecialisedcell.

Understandinghowstemcellscanbemodifiedhashugepotentialinmedicine.

Tounderstandhowawholeorganismfunctions,itisessentialtoappreciatetheimportanceofcooperationbetweencells,tissues,organsandorgansystems.



(a) the cell cycle To include the processes taking place during interphase (G1, S and G2), mitosis and cytokinesis, leadingtogeneticallyidenticalcells.

HSW8

(b) how the cell cycle is regulated To include an outline of the use of checkpoints to control the cycle.

(c) the main stages of mitosis To include the changes in the nuclear envelope, chromosomes,chromatids,centromere,centrioles,spindlefibresandcellmembrane.

HSW8

(d) sectionsofplanttissueshowingthecellcycleandstages of mitosis

Toincludetheexaminationofstainedsectionsandsquashesofplanttissueandtheproductionoflabelled diagrams to show the stages observed. PAG1

(e) thesignificanceofmitosisinlifecycles Toincludegrowth,tissuerepairandasexualreproductioninplants,animalsandfungi.

HSW2

(f) thesignificanceofmeiosisinlifecycles Toincludetheproductionofhaploidcellsandgeneticvariationbyindependentassortmentandcrossing over.

HSW2, HSW5


2

(g) the main stages of meiosis To include interphase, prophase 1, metaphase 1, anaphase 1, telophase 1, prophase 2, metaphase 2, anaphase 2, telophase 2 (no details of the names of the stages within prophase 1 are required) and the term homologous chromosomes. PAG1 HSW8

(h) howcellsofmulticellularorganismsarespecialisedforparticularfunctions

To include erythrocytes, neutrophils, squamous and ciliated epithelial cells, sperm cells, palisade cells, root hair cells and guard cells. PAG1

(i) theorganisationofcellsintotissues,organsandorgan systems

Toincludesquamousandciliatedepithelia,cartilage,muscle,xylemandphloemasexamplesoftissues.

(j) thefeaturesanddifferentiationofstemcells To include stem cells as a renewing source of undifferentiatedcells.

(k) theproductionoferythrocytesandneutrophilsderived from stem cells in bone marrow

(l) theproductionofxylemvesselsandphloemsieve tubes from meristems

(m) thepotentialusesofstemcellsinresearchandmedicine.

Toincludetherepairofdamagedtissues,thetreatmentofneurologicalconditionssuchasAlzheimers and Parkinsons, and research into developmental biology.

HSW2, HSW5, HSW6, HSW7, HSW9, HSW10, HSW11, HSW12


2

Module3:Exchangeandtransport

In this module, learners study the structure and functionofgasexchangeandtransportsystemsinarange of animals and in terrestrial plants.

Thesignificanceofsurfaceareatovolumeratioindeterminingtheneedforventilation,gasexchangeandtransportsystemsinmulticellularorganismsisemphasised. The examples of terrestrial green plants

and a range of animal phyla are used to illustrate the principle.


3.1Exchangeandtransport

3.1.1Exchangesurfaces

Asanimalsbecomelargerandmoreactive,ventilationandgasexchangesystemsbecomeessentialtosupplyoxygen to, and remove carbon dioxide from, their bodies.

Ventilationandgasexchangesystemsinmammals,bonyfishandinsectsareusedasexamplesofthepropertiesandfunctionsofexchangesurfacesinanimals.



(a) the need for specialised exchange surfaces Toincludesurfaceareatovolumeratio(SA:V),metabolicactivity,single-celledandmulticellularorganisms.

M0.1, M0.3, M0.4, M1.1, M2.1, M4.1 HSW1, HSW3, HSW5, HSW8

(b) thefeaturesofanefficientexchangesurface To include,

increased surface area root hair cells

thin layer alveoli

goodbloodsupply/ventilationtomaintaingradient gills/alveolus.

(c) thestructuresandfunctionsofthecomponentsof the mammalian gaseous exchange system

Toincludethedistributionandfunctionsofcartilage,ciliated epithelium, goblet cells, smooth muscle and elasticfibresinthetrachea,bronchi,bronchiolesand alveoli. PAG1 HSW8

(d) themechanismofventilationinmammals Toincludethefunctionoftheribcage,intercostalmuscles (internal and external) and diaphragm.

HSW8


2

(e) therelationshipbetweenvitalcapacity,tidalvolume, breathing rate and oxygen uptake

Toincludeanalysisandinterpretationofprimaryand secondary data e.g. from a data logger or spirometer.

M0.1, M0.2, M0.4, M1.3 PAG10 HSW2, HSW3, HSW4, HSW5, HSW6

(f) themechanismsofventilationandgasexchangeinbonyfishandinsects

To include:

bonyfishchangesinvolumeofthebuccalcavityandthefunctionsoftheoperculum,gillfilamentsandgilllamellae(gillplates);countercurrentflow

insects spiracles, trachea, thoracic and abdominal movement to change body volume,exchangewithtrachealfluid.

HSW8

(g) thedissection,examinationanddrawingofthegaseousexchangesystemofabonyfishand/orinsect trachea

PAG2HSW4

(h) theexaminationofmicroscopeslidestoshowthehistology of exchange surfaces.

PAG1HSW4

3.1.2Transportinanimals

Asanimalsbecomelargerandmoreactive,transportsystemsbecomeessentialtosupplynutrientsto,andremove waste from, individual cells.

Controlling the supply of nutrients and removal of wasterequiresthecoordinatedactivityoftheheartand circulatory system.



(a) theneedfortransportsystemsinmulticellularanimals

Toincludeanappreciationofsize,metabolicrateandsurfaceareatovolumeratio(SA:V).


(b) thedifferenttypesofcirculatorysystems To include single, double, open and closed circulatorysystemsininsects,fishandmammals.

(c) thestructureandfunctionsofarteries,arterioles,capillaries, venules and veins

Toincludethedistributionofdifferenttissueswithinthe vessel walls. PAG2


2

(d) theformationoftissuefluidfromplasma Toincludereferencetohydrostaticpressure,oncoticpressureandanexplanationofthedifferencesinthecompositionofblood,tissuefluidandlymph.

HSW8

(e) (i) the external and internal structure of the mammalian heart

(ii) thedissection,examinationanddrawingofthe external and internal structure of the mammalian heart

PAG2HSW4

(f) the cardiac cycle To include the role of the valves and the pressure changes occurring in the heart and associated vessels.

HSW2, HSW5, HSW8

(g) howheartactionisinitiatedandcoordinated To include the roles of the sino-atrial node (SAN), atrio-ventricularnode(AVN),purkynetissueandthe myogenic nature of cardiac muscle (no detail of hormonal and nervous control is required at AS level).

HSW2, HSW5, HSW8

(h) theuseandinterpretationofelectrocardiogram(ECG) traces

Toincludenormalandabnormalheartactivitye.g.tachycardia,bradycardia,fibrillationandectopicheartbeat.

M0.1, M1.1, M1.3, M2.4 HSW2, HSW5

(i) theroleofhaemoglobinintransportingoxygenand carbon dioxide

To include the reversible binding of oxygen molecules, carbonic anhydrase, haemoglobinic acid, HCO3

andthechlorideshift.

HSW8

(j) theoxygendissociationcurveforfetalandadulthuman haemoglobin.

Toincludethesignificanceofthedifferentaffinitiesfor oxygen AND thechangestothedissociationcurveatdifferentcarbondioxideconcentrations(theBohreffect).

M3.1 HSW2, HSW8


2

3.1.3Transportinplants

As plants become larger and more complex, transport systemsbecomeessentialtosupplynutrientsto,andremove waste from, individual cells.

The supply of nutrients from the soil relies upon the flowofwaterthroughavascularsystem,asdoesthemovement of the products of photosynthesis.



(a) theneedfortransportsystemsinmulticellularplants

Toincludeanappreciationofsize,metabolicrateandsurfaceareatovolumeratio(SA:V).


(b) (i) thestructureandfunctionofthevascularsystem in the roots, stems and leaves of herbaceous dicotyledonous plants

(ii) theexaminationanddrawingofstainedsectionsofplanttissuetoshowthedistributionofxylemandphloem

(iii) thedissectionofstems,bothlongitudinallyandtransversely,andtheirexaminationtodemonstratethepositionandstructureofxylem vessels

To include xylem vessels, sieve tube elements and companion cells.

PAG1HSW4

PAG2HSW4

(c) (i) theprocessoftranspirationandtheenvironmentalfactorsthataffecttranspirationrate

(ii) practicalinvestigationstoestimatetranspirationrates

Toincludeanappreciationthattranspirationisaconsequence of gaseous exchange.

To include the use of a potometer.

M0.1, M0.2, M1.1, M1.2, M1.3, M1.6, M1.11, M3.1, M3.2, M3.3, M3.5, M3.6, M4.1 PAG5,PAG11 HSW2, HSW3, HSW4, HSW5, HSW6, HSW8

(d) the transport of water into the plant, through the plant and to the air surrounding the leaves

To include details of the pathways taken by water AND the mechanisms of movement, in terms of water potential,adhesion,cohesionandthetranspirationstream.

HSW2, HSW8

(e) adaptationsofplantstotheavailabilityofwaterin their environment

Toincludexerophytes(cactiandmarramgrass)andhydrophytes (water lilies).

HSW2


2

(f) themechanismoftranslocation. Toincludetranslocationasanenergy-requiringprocesstransportingassimilates,especiallysucrose,in the phloem between sources (e.g. leaves) and sinks (e.g. roots, meristem) AND detailsofactiveloadingatthesourceandremovalat the sink.

HSW2, HSW8

Module4:Biodiversity,evolutionanddisease

In this module the learners study the biodiversity oforganisms;howtheyareclassifiedandthewaysin which biodiversity can be measured. It serves as anintroductiontoecology,emphasisingpracticaltechniquesandanappreciationoftheneedtomaintain biodiversity. The learners also gain an understanding of the variety of organisms that are pathogenic and the way in which plants and animals have evolved defences to deal with disease. The

impactoftheevolutionofpathogensonthetreatmentof disease is also considered.

Therelationshipsbetweenorganismsarestudied,consideringvariation,evolutionandphylogeny.


4.1Communicablediseases,diseasepreventionandtheimmunesystem

4.1.1Communicablediseases,diseasepreventionandtheimmunesystem

Organisms are surrounded by pathogens and have evolveddefencesagainstthem.Medicalinterventioncan be used to support these natural defences.

The mammalian immune system is introduced.



(a) thedifferenttypesofpathogenthatcancausecommunicable diseases in plants and animals

To include,

bacteria tuberculosis (TB), bacterial meningitis,ringrot(potatoes,tomatoes)

virusHIV/AIDS(human),influenza(animals),Tobacco Mosaic Virus (plants)

protoctistamalaria,potato/tomatolateblight

fungi black sigatoka (bananas), ring worm (cattle),athletesfoot(humans).


2

(b) the means of transmission of animal and plant communicable pathogens

To include direct and indirect transmission, referencetovectors,sporesandlivingconditions e.g. climate, social factors (no detail of the symptomsofspecificdiseasesisrequired).

M0.1, M0.2, M0.3, M1.1, M1.2, M1.3, M1.5, M1.7, M3.1, M3.2 HSW1, HSW2, HSW3, HSW5, HSW6, HSW7, HSW8, HSW11, HSW12

(c) plant defences against pathogens Toincludeproductionofchemicals AND plant responses that limit the spread of the pathogen(e.g.callosedeposition).

(d) theprimarynon-specificdefencesagainstpathogens in animals

Non-specificdefencestoincludeskin,bloodclotting,woundrepair,inflammation,expulsivereflexesandmucous membranes (no detail of skin structure is required).

HSW2, HSW8

(e) (i) thestructureandmodeofactionofphagocytes

(ii) examinationanddrawingofcellsobservedin blood smears

Toincludeneutrophilsandantigen-presentingcells AND the roles of cytokines, opsonins, phagosomes and lysosomes.

PAG1 HSW4, HSW8

(f) thestructure,differentrolesandmodesofactionofBandTlymphocytesinthespecificimmuneresponse

Toincludethesignificanceofcellsignalling(referencetointerleukins),clonalselectionandclonal expansion, plasma cells, T helper cells, T killer cells and T regulator cells.

HSW8

(g) the primary and secondary immune responses To include T memory cells and B memory cells.

M1.3 HSW2

(h) thestructureandgeneralfunctionsofantibodies Toincludethegeneralstructureofanantibodymolecule.

(i) anoutlineoftheactionofopsonins,agglutininsandanti-toxins

(j) thedifferencesbetweenactiveandpassiveimmunity,andbetweennaturalandartificialimmunity

To include examples of each type of immunity.

(k) autoimmune diseases Toincludeanappreciationofthetermautoimmune diseaseandanamedexamplee.g.arthritis,lupus.


2

(l) theprinciplesofvaccinationandtheroleofvaccinationprogrammesinthepreventionofepidemics

Toincluderoutinevaccinations AND reasonsforchangestovaccinesandvaccinationprogrammes (including global issues).

M0.1, M0.2, M0.3, M1.1, M1.2, M1.3, M1.5, M1.7, M3.1, M3.2 HSW1, HSW2, HSW3, HSW5, HSW6, HSW7, HSW8, HSW9, HSW11, HSW12

(m) possible sources of medicines To include examples of microorganisms and plants (and so the need to maintain biodiversity) AND thepotentialforpersonalisedmedicinesandsyntheticbiology.

HSW7, HSW9, HSW11, HSW12

(n) thebenefitsandrisksofusingantibioticstomanagebacterialinfection.

Toincludethewideuseofantibioticsfollowingthediscovery of penicillin in the mid-20th century AND theincreaseinbacterialresistancetoantibiotics(examples to include Clostridium difficile and MRSA) anditsimplications.



2

4.2Biodiversity

4.2.1Biodiversity

Biodiversity refers to the variety and complexity of life. It is an important indicator in the study of habitats.

Maintaining biodiversity is important for many reasons. Actionstomaintainbiodiversitymustbetakenatlocal,nationalandgloballevels.



(a) howbiodiversitymaybeconsideredatdifferentlevels

To include habitat biodiversity (e.g. sand dunes, woodland, meadows, streams), species biodiversity (speciesrichnessandspeciesevenness)andgeneticbiodiversity(e.g.differentbreedswithinaspecies).

(b) (i) how sampling is used in measuring the biodiversity of a habitat and the importance of sampling

(ii) practicalinvestigationscollectingrandomandnon-randomsamplesinthefield

To include how sampling can be carried out i.e. random sampling and non-random sampling (e.g.opportunistic,stratifiedandsystematic)andthe importance of sampling the range of organisms in a habitat.

M0.2, M1.3, M1.5, M1.4, M1.6, M1.7, M1.9, M1.10, M3.2 PAG3 HSW4, HSW5, HSW6

(c) how to measure species richness and species evenness in a habitat

M1.1, M1.5, M2.3, M2.4

(d) theuseandinterpretationofSimpsonsIndexof Diversity (D) to calculate the biodiversity of a habitat

To include the formula:

D = 1 ((n/N)2)

AND theinterpretationofbothhighandlowvaluesofSimpsons Index of Diversity (D).

M1.1, M1.5, M2.3, M2.4 HSW5


2

(e) howgeneticbiodiversitymaybeassessed,includingcalculations

Toincludecalculationsofgeneticdiversitywithinisolatedpopulations,forexamplethepercentageofgene variants (alleles) in a genome.

proportion of polymorphic gene loci =

number of polymorphic gene loci total number of loci

Suitablepopulationsincludezoos(captivebreeding),rare breeds and pedigree animals.

M1.1, M1.5, M2.3, M2.4 HSW5

(f) thefactorsaffectingbiodiversity Toincludehumanpopulationgrowth,agriculture(monoculture) and climate change.

M1.3, M1.7, M3.1 HSW5, HSW10, HSW12

(g) theecological,economicandaestheticreasonsfor maintaining biodiversity

Ecological,includingprotectingkeystonespecies(interdependence of organisms) and maintaining geneticresource

economic,includingreducingsoildepletion(continuousmonoculture)

aesthetic,includingprotecting

landscapes.

HSW12

(h) in situ and ex situ methods of maintaining biodiversity

In situconservationincludingmarineconservationzonesandwildlifereserves

ex situconservationincludingseedbanks,botanic gardens and zoos.


(i) internationalandlocalconservationagreementsmade to protect species and habitats.

Historic and/or current agreements, including the ConventiononInternationalTradeinEndangeredSpecies(CITES),theRioConventiononBiologicalDiversity (CBD) and the Countryside Stewardship Scheme (CSS).

HSW11, HSW12


2

4.2.2Classificationandevolution

Evolutionhasgeneratedaverywidevarietyoforganisms. The fact that all organisms share a common ancestryallowsthemtobeclassified.Classificationisanattempttoimposeahierarchyonthecomplexanddynamic variety of life on Earth.

Classificationsystemshavechangedandwillcontinueto change as our knowledge of the biology of organisms develops.



(a) thebiologicalclassificationofspecies To include the taxonomic hierarchy of kingdom, phylum, class, order, family, genus and species AND domain.


(b) the binomial system of naming species and the advantage of such a system

(c) (i) the features used to classify organisms into thefivekingdoms:Prokaryotae,Protoctista,Fungi, Plantae, Animalia

(ii) the evidence that has led to new classificationsystems,suchasthethreedomainsoflife,whichclarifiesrelationships

Toincludetheuseofsimilaritiesinobservablefeaturesinoriginalclassification.

Toincludethemorerecentuseofsimilaritiesinbiologicalmoleculesandothergeneticevidence AND details of the three domains and a comparison of thekingdomanddomainclassificationsystems.

HSW1, HSW5, HSW6, HSW7, HSW11, HSW12

(d) therelationshipbetweenclassificationandphylogeny

(covered in outline only at AS level)

HSW5, HSW7

(e) theevidenceforthetheoryofevolutionbynaturalselection

ToincludethecontributionofDarwinandWallaceinformulatingthetheoryofevolutionbynaturalselection AND fossil, DNA (only genomic DNA at AS level) and molecular evidence.

HSW1, HSW2, HSW5, HSW6, HSW7


2

(f) thedifferenttypesofvariation Toincludeintraspecificandinterspecificvariation AND thedifferencesbetweencontinuousanddiscontinuousvariation,usingexamplesofarangeofcharacteristicsfoundinplants,animalsandmicroorganisms AND bothgeneticandenvironmentalcausesofvariation.

Anopportunitytousestandarddeviationtomeasure the spread of a set of data and/or Students t-test to compare means of data values of twopopulations and/or theSpearmansrankcorrelationcoefficienttoconsidertherelationshipofthedata.

M1.2, M1.3, M1.6, M1.7, M1.10 HSW4

(g) thedifferenttypesofadaptationsoforganismstotheir environment

Anatomical, physiological and behavioural adaptations AND whyorganismsfromdifferenttaxonomicgroupsmay show similar anatomical features, including the marsupial mole and placental mole.

HSW5

(h) themechanismbywhichnaturalselectioncanaffectthecharacteristicsofapopulationovertime

Toincludeanappreciationthatgeneticvariation,selectionpressureandreproductivesuccess(orfailure)resultsinanincreasedproportionofthepopulationpossessingtheadvantageouscharacteristic(s).

M0.3 HSW8

(i) howevolutioninsomespecieshasimplicationsforhumanpopulations.

Toincludetheevolutionofpesticideresistanceininsects and drug resistance in microorganisms.

HSW8, HSW9, HSW12


2

Module5:Communication,homeostasisandenergy

It is important that organisms, both plants and animalsareabletorespondtostimuli.Thisisachievedbycommunicationwithinthebody,whichmay be chemical and/or electrical. Both systems are coveredindetailinthismodule.Communicationis also fundamental to homeostasis with control of temperature,bloodsugarandbloodwaterpotentialbeing studied as examples.

In this module, the biochemical pathways of photosynthesisandrespirationareconsidered,withanemphasisontheformationanduseofATPasthe source of energy for biochemical processes and synthesis of biological molecules.


5.1Communicationandhomeostasis

5.1.1Communicationandhomeostasis

Organisms use both chemical and electrical systems to monitorandrespondtoanydeviationfromthebodyssteady state.



(a) theneedforcommunicationsystemsinmulticellularorganisms

To include the need for animals and plants to respond to changes in the internal and external environmentandtocoordinatetheactivitiesofdifferentorgans.

(b) thecommunicationbetweencellsbycellsignalling

To include signalling between adjacent cells and signalling between distant cells.

(c) the principles of homeostasis Toincludethedifferencesbetweenreceptorsandeffectors,andthedifferencesbetweennegativefeedbackandpositivefeedback.

HSW8

(d) the physiological and behavioural responses involved in temperature control in ectotherms and endotherms.

To include, endotherms peripheral temperature

receptors, the role of the hypothalamus and effectorsinskinandmuscles;behaviouralresponses

ectotherms behavioural responses.

Anopportunitytomonitorphysiologicalfunctionsinectotherms and/or endotherms.

PAG11 HSW2


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5.1.2Excretionasanexampleofhomeostaticcontrol

The kidneys, liver and lungs are all involved in the removal of toxic products of metabolism from the blood and therefore contribute to homeostasis. The

kidneys play a major role in the control of the water potentialoftheblood.

The liver also metabolises some toxins that are ingested.



(a) the term excretion and its importance in maintaining metabolism and homeostasis

To include reference to the importance of removing metabolic wastes, including carbon dioxide and nitrogenous waste, from the body.

(b) (i) thestructureandfunctionsofthemammalian liver

(ii) theexaminationanddrawingofstainedsectionstoshowthehistologyoflivertissue

To include the gross structure and histology of the liver AND the roles of the liver in storage of glycogen, detoxificationandtheformationofurea(theornithine cycle covered in outline only).

PAG1HSW4

(c) (i) thestructure,mechanismsofactionandfunctionsofthemammaliankidney

(ii) thedissection,examinationanddrawingofthe external and internal structure of the kidney

(iii) theexaminationanddrawingofstainedsectionstoshowthehistologyofnephrons

To include the gross structure and histology of the kidney including the detailed structure of a nephron and its associated blood vessels AND theprocessesofultrafiltration,selectivereabsorptionandtheproductionofurine.

M0.1, M0.3, M1.1, M1.3, M2.1, M3.1 PAG1,PAG2 HSW4, HSW6, HSW8

(d) thecontrolofthewaterpotentialoftheblood To include the role of osmoreceptors in the hypothalamus, the posterior pituitary gland, ADH anditseffectonthewallsofthecollectingducts.

HSW8

(e) theeffectsofkidneyfailureanditspotentialtreatments

To include the problems that arise from kidney failureincludingtheeffectonglomerularfiltrationrate (GFR) and electrolyte balance AND the use of renal dialysis and transplants for the treatment of kidney failure.

HSW7, HSW9, HSW12


2

(f) how excretory products can be used in medical diagnosis.

Toincludetheuseofurinesamplesindiagnostictests, with reference to the use of monoclonal antibodiesinpregnancytestingandtestingforanabolic steroids and drugs.

PAG9 HSW7, HSW9, HSW11, HSW12

5.1.3Neuronalcommunication

Thestimulationofsensoryreceptorsleadstothegenerationofanactionpotentialinaneurone.

Transmission between neurones takes place at synapses.



(a) the roles of mammalian sensory receptors in convertingdifferenttypesofstimuliintonerveimpulses

To include an outline of the roles of sensory receptors (e.g. Pacinian corpuscle) in responding tospecifictypesofstimuliandtheirrolesastransducers.

(b) thestructureandfunctionsofsensory,relayandmotor neurones

Toincludedifferencesbetweenthestructureandfunctionofmyelinatedandnon-myelinatedneurones.

(c) thegenerationandtransmissionofnerveimpulses in mammals

Toincludehowtherestingpotentialisestablishedandmaintainedandhowanactionpotentialisgenerated(includingreferencetopositivefeedback)andtransmittedinamyelinatedneurone AND thesignificanceofthefrequencyofimpulsetransmission.

M1.3, M3.1

(d) the structure and roles of synapses in neurotransmission.

To include the structure of a cholinergic synapse AND theactionofneurotransmittersatthesynapseandtheimportanceofsynapsesinsummationandcontrol.


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5.1.4Hormonalcommunication

Thewaysinwhichspecifichormonesbringabouttheireffectsareusedtoexemplifyendocrinecommunicationandcontrol.Treatmentofdiabetesis

used as an example of the use of medical technology in overcoming defects in hormonal control systems.



(a) endocrinecommunicationbyhormones Toincludesecretionofhormonesintotheblood,transportbytheblood,anddetectionbytargetcellsortissues.

(b) thestructureandfunctionsoftheadrenalglands Adrenal glands as an example of endocrine glands, to include the hormones secreted by the cortex and medullaandtheirfunctions.

(c) (i) the histology of the pancreas(ii) theexaminationanddrawingofstained

sectionsofthepancreastoshowthehistologyoftheendocrinetissues

Toincludetheendocrinetissues.

PAG1 HSW4

(d) howbloodglucoseconcentrationisregulated Toincludetheactionofinsulinandglucagonasanexampleofnegativefeedback,andtheroleoftheliver AND thecontrolofinsulinsecretion,withreferencetopotassium channels and calcium channels in the beta cells of the pancreas.

HSW12

(e) thedifferencesbetweenType1andType2diabetes mellitus

To include the causes of Type 1 and Type 2 diabetes and the treatments used for each.

HSW12

(f) thepotentialtreatmentsfordiabetesmellitus. Toincludetheuseofinsulinproducedbygeneticallymodifiedbacteriaandthepotentialuseofstemcellsto treat diabetes mellitus.

HSW12


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5.1.5Plantandanimalresponses

Plant responses to environmental changes are coordinated by hormones, some of which are important commercially.

In animals, responding to changes in the environment isacomplexandcontinuousprocess,involvingnervous,hormonalandmuscularcoordination.



(a) (i) the types of plant responses(ii) practicalinvestigationsintophototropism

and geotropism

Toincludetheresponsetoabioticstressandherbivory e.g. chemical defences (such as tannins, alkaloids and pheromones), folding in response to touch (Mimosa pudica) AND the range of tropisms in plants.

M1.3, M1.6 PAG11 HSW4

(b) the roles of plant hormones To include the role of hormones in leaf loss in deciduousplants,seedgerminationandstomatalclosure.

(c) the experimental evidence for the role of auxins in the control of apical dominance

HSW5

(d) the experimental evidence for the role of gibberellininthecontrolofstemelongationandseedgermination

HSW5

(e) practicalinvestigationsintotheeffectofplanthormones on growth

Anopportunityforserialdilution.

Anopportunitytousestandarddeviationtomeasure the spread of a set of data.

M0.2, M1.1, M1.2, M1.3, M1.4, M1.6, M1.9, M1.10, M3.1, M3.2 PAG11 HSW4

(f) the commercial use of plant hormones To include the use of hormones to control ripening, theuseofrootingpowdersandhormonalweedkillers.

HSW12

(g) theorganisationofthemammaliannervoussystem

Toincludethestructuralorganisationofthenervoussystem into the central and peripheral systems AND thefunctionalorganisationintothesomaticandautonomic nervous systems.


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(h) the structure of the human brain and the functionsofitsparts

To include the gross structure of the human brain AND thefunctionsofthecerebrum,cerebellum,medullaoblongata, hypothalamus and pituitary gland.

(i) reflexactions Toincludekneejerkreflexandblinkingreflex,withreferencetothesurvivalvalueofreflexactions.

M0.1, M0.2, M1.1, M1.2, M1.3, M1.6 PAG11 HSW4

(j) thecoordinationofresponsesbythenervousand endocrine systems

Toincludethefightorflightresponsetoenvironmentalstimuliinmammals AND theactionofhormonesincellsignalling(studiedinoutlineonly)withreferencetoadrenaline(firstmessenger),activationofadenylylcyclase,andcyclicAMP (second messenger).

(k) theeffectsofhormonesandnervousmechanisms on heart rate

Anopportunitytomonitorphysiologicalfunctions,for example with pulse rate measurements before, duringandafterexerciseorsensorstorecordelectricalactivityintheheart.

Anopportunitytousestandarddeviationtomeasure the spread of a set of data and/or Students t-test to compare means of data values of two sets of data.

M0.1, M0.2, M0.3, M1.1, M1.2, M1.3, M1.6, M1.10, M3.1 PAG10,PAG11

(l) (i) the structure of mammalian muscle and the mechanismofmuscularcontraction

(ii) theexaminationofstainedsectionsorphotomicrographs of skeletal muscle.

Toincludethestructuralandfunctionaldifferencesbetween skeletal, involuntary and cardiac muscle AND theactionofneuromuscularjunctions AND theslidingfilamentmodelofmuscularcontractionand the role of ATP, and how the supply of ATP is maintainedinmusclesbycreatinephosphate.

Anopportunitytomonitormusclecontractionandfatigueusingsensorstorecordelectricalactivity.

PAG1,PAG10,PAG11 HSW4


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5.2Energyforbiologicalprocesses

5.2.1Photosynthesis

Photosynthesis is the process whereby light from the Sunisharvestedandusedtodrivetheproductionof

chemicals, including ATP, and used to synthesise large organic molecules from inorganic molecules.



(a) theinterrelationshipbetweentheprocessofphotosynthesisandrespiration

Toincludetherelationshipbetweentherawmaterials and products of the two processes.

M0.1, M0.3, M0.4, M3.4

(b) the structure of a chloroplast and the sites of the two main stages of photosynthesis

The components of a chloroplast including outer membrane, lamellae, grana, thylakoid, stroma and DNA.

(c) (i) theimportanceofphotosyntheticpigmentsin photosynthesis

(ii) practicalinvestigationsusingthinlayerchromatography (TLC) to separate photosyntheticpigments

Toincludereferencetolightharvestingsystemsandphotosystems.

M0.1, M0.2, M1.1, M1.3, M2.2, M2.3, M2.4 PAG6 HSW4

(d) the light-dependent stage of photosynthesis To include how energy from light is harvested and usedtodrivetheproductionofchemicalswhichcanbe used as a source of energy for other metabolic processes (ATP and reduced NADP) with reference to electron carriers and cyclic and non-cyclic photophosphorylation AND the role of water.

HSW8

(e) thefixationofcarbondioxideandthelight-independent stage of photosynthesis

To include how the products of the light-dependent stage are used in the light-independent stage (Calvin cycle) to produce triose phosphate (TP) with reference to ribulose bisphosphate (RuBP), ribulose bisphosphate carboxylase (RuBisCO) and glycerate 3-phosphate (GP) no other biochemical detail is required.

HSW8

(f) the uses of triose phosphate (TP) ToincludetheuseofTPasastartingmaterialforthesynthesis of carbohydrates, lipids and amino acids AND the recycling of TP to regenerate the supply of RuBP.


2

(g) (i) factorsaffectingphotosynthesis(ii) practicalinvestigationsintofactorsaffecting

the rate of photosynthesis.

Toincludelimitingfactorsinphotosynthesiswithreferencetocarbondioxideconcentration,lightintensityandtemperature,andtheimplicationsofwater stress (stomatal closure) AND theeffectontherateofphotosynthesis,andonlevels of GP, RuBP and TP, of changing carbon dioxideconcentration,lightintensityandtemperature.

An opportunity to use sensors, data loggers and softwaretoprocessdata.

M0.1, M0.2, M0.3, M1.1, M1.3, M1.11, M3.1, M3.2, M3.4, M3.5, M3.6, M4.1 PAG4,PAG10,PAG11 HSW3, HSW4, HSW5, HSW12

5.2.2Respiration

Respirationistheprocesswherebyenergystoredincomplex organic molecules is transferred to ATP. ATP

provides the immediate source of energy for biological processes.



(a) theneedforcellularrespiration To include examples of why plants, animals and microorganisms need to respire (suitable examples couldincludeactivetransportandanoutlineofnamedmetabolicreactions).

(b) the structure of the mitochondrion The components of a mitochondrion including inner and outer michondrial membranes, cristae, matrix and mitochondrial DNA.

(c) the process and site of glycolysis Toincludethephosphorylationofglucosetohexosebisphosphate,thesplittingofhexosebisphosphateinto two triose phosphate molecules and further oxidationtopyruvate AND theproductionofasmallyieldofATPandreducedNAD.

HSW8

(d) thelinkreactionanditssiteinthecell Toincludethedecarboxylationofpyruvatetoacetate,thereductionofNAD,andthecombinationof acetate with coenzyme A.


2

(e) the process and site of the Krebs cycle Toincludetheformationofcitratefromacetateand oxaloacetate and the reconversion of citrate to oxaloacetate (names of intermediate compounds are not required) AND theimportanceofdecarboxylation,dehydrogenation,thereductionofNADandFAD,andsubstratelevelphosphorylation.

HSW8

(f) the importance of coenzymes in cellular respiration

With reference to NAD, FAD and coenzyme A.

(g) theprocessandsiteofoxidativephosphorylation To include the roles of electron carriers, oxygen and the mitochondrial cristae.

(h) thechemiosmotictheory To include the electron transport chain, protongradientsandATPsynthaseinoxidativephosphorylationandphotophosphorylation.

(i) (i) theprocessofanaerobicrespirationineukaryotes

(ii) practicalinvestigationsintorespirationrates in yeast, under aerobic and anaerobic conditions

Toincludeanaerobicrespirationinmammalsandyeastandthebenefitsofbeingabletorespireanaerobically AND whyanaerobicrespirationproducesamuchloweryieldofATPthanaerobicrespiration.


M0.1, M0.2, M1.1, M1.3, M2.4, M3.1, M3.2 PAG4,PAG10,PAG11 HSW3, HSW4

(j) thedifferenceinrelativeenergyvaluesofcarbohydrates, lipids and proteins as respiratory substrates

(k) theuseandinterpretationoftherespiratoryquotient(RQ)

Toincludecalculatingtherespiratoryquotient(RQ)using the formula:

RQ = CO2 producedO2 consumed

M0.1, M0.2, M1.1, M1.3, M2.3


2

(l) practicalinvestigationsintotheeffectoffactorssuchastemperature,substrateconcentrationanddifferentrespiratorysubstratesontherateofrespiration.

For example the use of respirometers.


Anopportunitytousestandarddeviationtomeasure the spread of a set of data and/or Students t-test to compare means of data values of two sets of data.

M0.1, M0.2, M1.1, M1.2, M1.3, M1.6, M1.10, M2.4, M3.2, M3.3, M3.5, M3.6 PAG4,PAG10,PAG11 HSW3, HSW4

Module6:Genetics,evolutionandecosystems

Thismodulecoverstheroleofgenesinregulatingandcontrollingcellfunctionanddevelopment.Heredityandthemechanismsofevolutionandspeciationarealso covered.

SomeofthepracticaltechniquesusedtomanipulateDNAsuchassequencingandamplificationareconsideredandtheirtherapeuticmedicaluse.Theuseof microorganisms in biotechnology is also covered. Bothofthesehaveassociatedethicalconsiderationsand it is important that learners develop a balanced understanding of such issues.

Learnersgainanappreciationoftheroleofmicroorganisms in recycling materials within the environment and maintaining balance within ecosystems. The need to conserve environmental resources in a sustainable fashion is considered, whilst appreciatingthepotentialconflictarisingfromtheneedsofanincreasinghumanpopulation.Learnersalsoconsidertheimpactsofhumanactivitiesonthenatural environment and biodiversity.


6.1Geneticsandevolution

6.1.1Cellularcontrol

Thewayinwhichcellscontrolmetabolicreactionsdetermines how organisms, grow, develop and function.



(a) typesofgenemutationsandtheirpossibleeffectsonproteinproductionandfunction

Toincludesubstitution,insertionordeletionofoneormorenucleotides AND thepossibleeffectsofthesegenemutations (i.e.beneficial,neutralorharmful).


2

(b) the regulatory mechanisms that control gene expressionatthetranscriptionallevel,post-transcriptionallevelandpost-translationallevel

To include control at the, transcriptionallevel:lac operon, and

transcriptionfactorsineukaryotes. post-transcriptionallevel:theeditingof

primary mRNA and the removal of introns to produce mature mRNA.

post-translationallevel:theactivationofproteins by cyclic AMP.

HSW2

(c) thegeneticcontrolofthedevelopmentofbodyplansindifferentorganisms

Homeobox gene sequences in plants, animals and fungi are similar and highly conserved AND the role of Hox genes in controlling body plan development.

HSW7

(d) the importance of mitosis and apoptosis as mechanisms controlling the development of body form.

Toincludeanappreciationthatthegeneswhichregulate the cell cycle and apoptosis are able to respondtointernalandexternalcellstimuli e.g. stress.

6.1.2Patternsofinheritance

Isolatingmechanismscanleadtotheaccumulationofdifferentgeneticinformationinpopulations,potentiallyleadingtonewspecies.Overaprolongedperiodoftime,organismshavechangedandsome

havebecomeextinct.Thetheoryofevolutionexplainsthesechanges.Humansuseartificialselectiontoproduce similar changes in plants and animals.



(a) (i) thecontributionofbothenvironmentalandgeneticfactorstophenotypicvariation

(ii) howsexualreproductioncanleadtogeneticvariationwithinaspecies

Toincludeexamplesofbothgeneticandenvironmentalcontributionsenvironmentalexamples could include diet in animals and etiolationorchlorosisinplants.

Meiosis and the random fusion of gametes at fertilisation.

(b) (i) geneticdiagramstoshowpatternsofinheritance

(ii) theuseofphenotypicratiostoidentifylinkage (autosomal and sex linkage) and epistasis

To include monogenic inheritance, dihybrid inheritance,multiplealleles,sexlinkageandcodominance.

Toincludeexplanationsoflinkageandepistasis.

M0.3, M1.4 HSW2, HSW8


2

(c) using the chi-squared (2) test to determine the significanceofthedifferencebetweenobservedand expected results

The formula for the chi-squared (2) test will be provided.

M0.3, M1.4, M1.9, M2.1

(d) thegeneticbasisofcontinuousanddiscontinuousvariation

To include reference to the number of genes that influenceeachtypeofvariation.

(e) thefactorsthatcanaffecttheevolutionofaspecies

Toincludestabilisingselectionanddirectionalselection,geneticdrift,geneticbottleneckandfoundereffect.

(f) the use of the HardyWeinberg principle to calculateallelefrequenciesinpopulations

TheequationsfortheHardyWeinbergprinciplewillbe provided.

M0.2, M2.1, M2.2, M2.3

(g) theroleofisolatingmechanismsintheevolutionof new species

To include geographical mechanisms (allopatric speciation)andreproductivemechanisms(sympatricspeciation).

(h) (i) theprinciplesofartificialselectionanditsuses

(ii) theethicalconsiderationssurroundingtheuseofartificialselection.

Toincludeexamplesofselectivebreedinginplantsand animals AND anappreciationoftheimportanceofmaintainingaresourceofgeneticmaterialforuseinselectivebreeding including wild types.

Toincludeaconsiderationofthemoreextremeexamplesoftheuseofartificialselectiontoimprovedomesticspeciese.g.dogbreeds.



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6.1.3Manipulatinggenomes

Genomesequencinggivesinformationaboutthelocationofgenesandprovidesevidencefortheevolutionarylinksbetweenorganisms.

Geneticengineeringinvolvesthemanipulationofnaturally occurring processes and enzymes. The

capacitytomanipulategeneshasmanypotentialbenefits,buttheimplicationsofgenetictechniquesaresubject to much public debate



(a) the principles of DNA sequencing and the development of new DNA sequencing techniques

To include the rapid advancements of the techniques used in sequencing, which have increased the speed of sequencing and allowed whole genome sequencing e.g. high-throughput sequencing.

HSW7

(b) (i) how gene sequencing has allowed for genome-wide comparisons between individuals and between species

(ii) how gene sequencing has allowed for the sequencesofaminoacidsinpolypeptidestobe predicted

(iii) how gene sequencing has allowed for the developmentofsyntheticbiology

Withreferencetobioinformaticsandcomputationalbiologyandhowthesefieldsarecontributingtobiological research into genotypephenotype relationships,epidemiologyandsearchingforevolutionaryrelationships.

PAG10 HSW7, HSW9

(c) theprinciplesofDNAprofilinganditsuses To include forensics and analysis of disease risk.

HSW9

(d) theprinciplesofthepolymerasechainreaction(PCR)anditsapplicationinDNAanalysis

(e) the principles and uses of electrophoresis for separatingnucleicacidfragmentsorproteins

Opportunityforpracticaluseofelectrophoresis.

PAG6HSW4

(f) (i) theprinciplesofgeneticengineering

(ii) thetechniquesusedingeneticengineering

Toincludetheisolationofgenesfromoneorganismand the placing of these genes into another organism using suitable vectors.

Toincludetheuseofrestrictionenzymes,plasmidsand DNA ligase to form recombinant DNA with the desiredgeneandelectroporation.

HSW2


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(g) theethicalissues(bothpositiveandnegative)relatingtothegeneticmanipulationofanimals(including humans), plants and microorganisms

Toincludeinsectresistanceingeneticallymodifiedsoya,geneticallymodifiedpathogensforresearchandpharmingi.e.geneticallymodifiedanimalstoproducepharmaceuticals AND issuesrelatingtopatentingandtechnologytransfere.g.makinggeneticallymodifiedseedavailabletopoor farmers.

HSW10

(h) theprinciplesof,andpotentialfor,genetherapyin medicine.

Toincludethedifferencesbetweensomaticcellgenetherapy and germ line cell gene therapy.

HSW9, HSW12

6.2Cloningandbiotechnology

6.2.1Cloningandbiotechnology

Farmersandgrowersexploitnaturalvegetativepropagationintheproductionofuniformcrops.Artificialclonesofplantsandanimalscannowbeproduced.

Biotechnology is the industrial use of living organisms (or parts of living organisms) to produce food, drugs or other product.


Learners should be able to demonstrate and apply their knowledge an

171736 Specification Accredited a Level Gce Biology a h420

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