[ARCHIVED] 24970 Uk Quals Gce Biology as 8042 24970

Edexcel GCE

Teachers� guide

Edexcel Advanced Subsidiary GCE in Biology8040 and Biology (Human) 8042First examination 2001Edexcel Advanced GCE in Biology 9040 andBiology (Human) 9042First examination 2002June 2000

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Publications Code UA007577

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CONTENTS

1 Practical Work in AS Biology and Biology (Human) 1Please note that the Guide to Practical Work in the A2 unitswill follow in Autumn 2000.

2 Booklist and Resource Suggestions 26

3 Glossary of Terms used in Examination Questions 32

4 The Mapping Document 33

UA007577 − Edexcel AS/Advanced GCE Biology (Human) Teachers� Guide 1

PRACTICAL WORK IN AS BIOLOGY AND BIOLOGY (HUMAN)

Introduction

Practical work is an integral part of the specifications and should be encouraged whereverpossible. One of the assessment objectives (Experiment and investigation, AO3), for both ASand Advanced GCE, relates specifically to the assessment of candidates� experience ofpractical activities. This assessment objective states that students should be able to:

! devise and plan experimental activities, selecting appropriate techniques

! demonstrate safe and skilful practical techniques

! make observations and measurements with appropriate precision and record thesemethodically

! interpret, explain, evaluate and communicate the results of their experimentalactivities using biological knowledge and understanding and employing appropriatespecialist vocabulary.

Further details of the experimental and investigative skills are given on pages 9 - 10 of theSpecifications.

Assessment Unit 3, Energy and the Environment, includes two assessment components:

❏ Paper 01 T1 Practical assessment of coursework

❏ Paper 03 Written test.

" For Paper 01, students will present an individual investigation which will be teacherassessed. This is intended to give students the opportunity to plan and carry out ascientific investigation. The investigation must be quantitative and must be linked toUnits 1, 2 or 3 in the AS specification. Full details of the allocation of marks andassessment of the individual investigation are given in the Specifications. The aims ofthis booklet are to outline the practical activities included in Units 1, 2 and 3 (indicated by❏) and to give suggestions for the development of some of these activities for thepurposes of individual investigations (indicated by •).

A note on safetyTeachers should be aware of their obligations under the Health and Safety atWork Act, Control of Substances Hazardous to Health (COSHH) Regulationsand the Management of Health and Safety at Work Regulations. When planningthe Individual Investigation, students should be encouraged to carry out theirown risk assessments to identify hazards and plan suitable ways of reducing therisks arising from them, before carrying out practical work.

2 UA007577 − Edexcel AS/Advanced GCE Biology (Human) Teachers� Guide

Unit 1 Molecules and cells

Practical work listed in the specification for this Unit includes:

❏ qualitative and quantitative biochemical tests for starch, reducing and non-reducing sugars and proteins

❏ experiments to investigate the effects of temperature, pH and enzymeconcentration on enzyme activity

❏ illustrations of enzyme immobilisation using lactase

❏ the use of pectinase in the production of fruit juice

❏ setting up and using a light microscope and using a graticule to makemeasurements

❏ preparation of root tip squashes to study stages in mitosis

❏ Qualitative and quantitative biochemical tests for starch, reducing and non-reducing sugars and proteins

The starch test using iodine solution can be made quantitative using a range of standard starchsolutions and iodine, the intensity of the resulting blue colour is then determined with acolorimeter. This reaction could be combined with the investigating of the activity ofamylase, by testing a small volume of the reaction mixture with iodine solution at suitabletime intervals. As an alternative, the use of starch-agar plates is suggested for quantitativework.

Starch-agar plates

Add 1 g of soluble starch to 10 cm3 of distilled water and mix. Add 1.2 g of agar powder to95 cm3 of distilled water and boil to dissolve the agar, stirring constantly, then add the starchsuspension whilst continuing to stir. Allow the mixture to cool, then pour about 25 cm3 intoeach sterile Petri dishes.

To investigate amylase activity, cut wells in the agar using an alcohol-flamed cork borer, andremove agar plugs using a cocktail stick. Place one or two drops of the enzyme solution intoeach well, using a Pasteur pipette. The plates are then incubated at 25 °C for 72 hours. Todevelop the plates, flood with dilute iodine solution and, when the blue-black colour hasdeveloped, rinse away the excess iodine solution with tap water. Clear zones will appear inthe agar where starch has been hydrolysed; the diameter of the clear zone is proportional tothe amylase activity. This method could be used to investigate changes in amylase activityduring germination of cereal grains, or to compare the activity of amylases from differentsources. A reddish coloured ring may be seen around the edge of the clear zone; this is due tothe presence of dextrins.


Tests for reducing and non-reducing sugars

Benedict�s solution is recommended as a reagent for the detection of reducing sugars. Thismethod can be made semi-quantitative by using a range of colour standards, such as a seriesof glucose solutions of known concentrations, for example, 2.0, 1.0, 0.5, 0.2, 0.1, 0.05, 0.02,and 0.01 per cent. Add 0.3 cm3 of each solution separately to labelled test tubes containing 5cm3 of Benedict�s solution. The test tubes are then placed in a boiling water bath for 8minutes, then left to cool.

Diabur � Test 5000 glucose reagent test strips (Roche, obtainable from pharmacists) providea useful method for the detection of glucose and are quantitative over the range 0 to 5 per cent(or 0 to 280 mmol per dm3). These are particularly useful when testing small volumes ofsolutions, such as drops from a simple bioreactor containing immobilised lactase.

Sucrose (a non-reducing sugar) may be hydrolysed with dilute hydrochloric acid in a boilingwater bath. The tube is then cooled and the excess acid neutralised by the addition of sodiumhydrogencarbonate, before applying a test for reducing sugar. As an alternative, add one dropof sucrase (invertase) concentrate to 5 cm3 of sucrose solution, leave for 30 minutes, thenapply a test for reducing sugars.

Tests for proteins

Biuret reagent is recommended for the detection of proteins. This method may also be madequantitative by using a standard range of protein solutions and a colorimeter. Powderedalbumen can be used to make up the protein standards. Albustix reagent strips (availablefrom pharmacists) are also useful as a quantitative test for proteins; and give a range ofcolours indicating some protein concentrations from 0 to 20 g per dm3.

Suppliers

# Agar powder# Albumen# Benedict�s solution# Biuret reagent# Iodine solution# Soluble starch# Sucrase (invertase)

are all available from Griffin Education and Philip Harris Education.Invertase is also available from the National Centre for Biotechnology Education.


❏ Experiments to investigate the effects of temperature, pH and enzymeconcentration on enzyme activity

Standard laboratory experiments to investigate the effects of temperature, pH and enzymeconcentration on enzyme activity are described in Molecules and Cells. Practical work usingenzymes provides numerous opportunities for individual investigations, some of which areoutlined below. In all experiments, students should be encouraged to use suitable controls.

Some opportunities for individual investigations

• Compare the activity of different milk-clotting enzymes. Practical work with rennet isdescribed in Tools, Techniques and Assessment in Biology. �Essence of rennet�, is availablefrom some chemists and supermarkets, such as Waitrose. VegeRen, a rennet substituteproduced by Mucor meihei, is also available from some health food shops. There are alsoseveral other rennet substitutes, such as Fromase (a fungal protease) and Maxiren (calfchymosin produced by genetically modified yeast). The activity of these enzymes could becompared at a range of concentrations, and at different temperatures, by investigating theclotting time of pasteurised milk samples (UHT milk is not suitable). If the test tubescontaining the milk and enzyme mixtures are tilted carefully, the appearance of granules inthe milk indicates that protein coagulation has started.

• Investigate the effect of calcium ions on the activity of rennet, using calcium chloridesolutions. Initially, a concentration of 0.01 mol per dm3 could be tried.

• Investigate the effect of copper ions on the activity of enzymes. Prepare a stocksolution of 1.0 mol per dm3 copper sulphate, then prepare three dilutions, 1:10, 1:100, and1:1000, to give concentrations of 0.1 mol per dm3, 0.01 mol per dm3, and 0.001 mol per dm3

respectively.Mix 1 cm3 of each copper sulphate solution with 0.3 cm3 of enzyme solution,leave to stand at room temperature for 10 minutes before investigating enzyme activity.

• Compare the rates of denaturation of enzymes, such as fungal and bacterial amylases.

• Investigate the activity of proteases. Protease activity can be investigated using stripsof photographic film; the time taken for the film to become transparent gives a measure ofprotease activity. Various proteases, including Alcalase and Savinase are available fromthe National Centre for Biotechnology Education. Protease activity in biological washingpowders, or proteases in plant material, such as bromelain in pineapples and papain from thepawpaw fruit, could be investigated using this simple method. Papain and bromelain tabletscan be bought from health food shops e.g. Holland & Barrett.

Students could also investigate the activity of proteases using gelatin plates. Prepareblackcurrant jelly and pour 25 cm3 into each Petri dish. The jelly must be made up in lesswater than stated on the packet, otherwise it will be too soft for plugs to be cut. For bestresults use about 1/3rd of the amount of water stated on the jelly packet. Allow the jelly to setand harden in a refrigerator, then carefully cut out wells using a 1 cm diameter cork borer.


Plugs of jelly can be removed using a cotton bud. Add one drop of enzyme solution to eachwell then leave for 12 hours at 25 °C. After incubation remove the liquefied gelatin using apipette and measure the diameter of the clear area. As an alternative to gelatin, students couldtry using casein agar. Add 1.2 g of agar powder to 100 cm3 of distilled water and boil, withconstant stirring, to dissolve the agar. Allow to cool, then add 1 g of Marvel milk powder,stir, and pour 25 cm3 into each Petri dish. Wells are cut in the agar in the same way as forstarch agar and, after incubation at 40 °C for one to two hours, the diameter of the clear zonesaround each well is measured to indicate protease activity.

• Investigate the activity of pectin methylesterase. Students could investigate the effectof enzyme concentration, temperature, and calcium ion concentration on the activity of pectinmethylesterase. This enzyme, when added to a pectin solution, causes the pectin to gel. Asuitable substrate to use is Certo, available from supermarkets, which contains an extract ofapple pectin. It is very important to use methylated pectin (such as apple pectin) as otherforms of pectin will not solidify.

❏ Illustrations of enzyme immobilisation using lactase

Immobilised enzymes are now used in many industrial processes and immobilisedlactase, for the production of lactose-reduced milk, is used as an illustration of one suchapplication. To prepare the immobilised enzyme, make up a 4 per cent solution of sodiumalginate in distilled or deionised water. Do not use tap water as calcium ions will cause thealginate to set. Add the alginate gradually to warm water, stirring all the time. For largevolumes, a food blender can be used to mix the alginate powder and distilled water. Thealginate solution is then mixed with an equal volume of enzyme solution and added one dropat a time to a 1.5 per cent solution of calcium chloride, to form the immobilised enzymebeads. When setting up the bioreactor, it is important to place a small piece of gauze in thesyringe barrel to prevent beads from blocking the nozzle. The glucose which is produced bythe activity of lactase is conveniently measured using Diabur �Test 5000 reagent test strips.


• Investigate the effect of bead size on enzyme activity. Beads of different sizes can beprepared by using hypodermic needles, of different gauges, attached to the syringe.As an alternative, use disposable plastic pipettes. These can be cut to different lengthsto produce beads of different diameters.

• Investigate the effect of substrate flow rate on immobilised enzyme activity. Flowrate can be altered by using a dropping funnel to add the substrate to a bioreactorcontaining immobilised enzyme beads.


❏ The use of pectinase in the production of fruit juice

For this practical, whole apples chopped into small pieces or minced, or tinned apple purée,are used to illustrate the effect of pectinase on the yield of juice. Put equal masses of choppedapple into 2 beakers, add 2 cm3 of diluted pectinase (1 cm3 of Pectinex plus 1 cm3 ofdistilled water) to one beaker and 2 cm3 of distilled water to the other. Stir thoroughly, thenplace both beakers in a water bath at 40 °C for 15 to 20 minutes. Filter the juice intomeasuring cylinders and record the volumes of juice produced.


• Investigate the rate at which juice is produced.

• Compare the yields of juice from different varieties of apples, or different types offruits.

• Investigate the effect of temperature on activity of pectinase.

• Investigate the effects of using pectinase and cellulase on juice production.

• Investigate the effects of pectinase on the clarification of cloudy apple juice(obtainable in cartons from Sainsbury�s and other supermarkets).

Suppliers

Philip Harris Education supplies a range of enzymes, including amylases, cellulase,pectinase, proteases and rennet, and exposed film to use as a substrate for proteases. PhilipHarris Education also supplies a range of complete kits for the investigation of enzymeactivity, including an enzyme biotechnology kit and an immobilised enzyme kit.

The National Centre for Biotechnology Education (NCBE) supplies a number of high-quality industrial grade enzymes, including amylase, amyloglucosidase, cellulase, glucoseisomerase, invertase, lactase, pectinase, pectin methylesterase, protease, fungal �rennin�, andpure chymosin. A washing powder enzymes pack, and an immobilised enzyme pack, are alsoavailable. The packs include safety guidelines, full technical data and details of practicalwork.

Reference

Full details of enzyme practicals, and suggestions for further work, areincluded in Practical Biotechnology - a guide for schools and colleges,published by the National Centre for Biotechnology Education.


Investigating the use of pectinase in the production of fruit juice

Measuring cylinder

Filter funnelcontaining apple pulpand pectinase solution


Making immobilised enzymes

Alginate beads formand harden in calciumchloride solution

Mixture added onedrop at a time tocalcium chloridesolution

Syringe containingsodium alginate andenzyme solution


A simple bioreactor

Dropping funnelcontaining substratesolution

Plastic syringe barrelcontaining immobilisedenzyme beads

Beaker to collectproducts

Gauze


❏ Setting up and using a light microscope and using a graticule to makemeasurements

Setting up and using a microscope, and the use of a graticule, are described in Molecules andCells and in Tools, Techniques and Assessment in Biology. Students are expected to befamiliar with the use of a microscope to make accurate observations and measurements. Theywill be required to use these skills in, for example, stomatal counts and investigation ofpollen tube growth.

❏ Preparation of root tip squashes to study stages in mitosis

This practical is described in Molecules and Cells and the use of garlic root tips isrecommended as a reliable source of actively dividing cells. As an alternative, Crocusbalansae, which has a diploid number of six large chromosomes, is also recommended. Asan alternative to the Feulgen method for staining chromosomes, staining with toluidine bluegives good results. Root tips are softened in 5 mol dm-3 hydrochloric acid for four minutes,then rinsed in water. Root tips are then placed on a microscope slide and toluidine blue (0.05per cent) added. Leave for five minutes, then remove all but the apical 2 mm of the root tipwith a scalpel. Apply a coverslip, cover with a tissue and squash carefully.


• This practical could be developed into an individual investigation by, for example,comparing mitotic indices of two different species, or by harvesting root tips hourly toinvestigate whether mitotic activity varies at different times of the day.

Suppliers

Crocus balansae corms are available during the autumn term only from Philip HarrisEducation.

Toluidine blue is also available from Philip Harris Education.


Unit 2B Exchange, transport and reproduction

Practical work in this Unit includes:

❏ the use of simple respirometers

❏ demonstration and measurement of transpiration, stomatal counts

❏ microscopic examination of stained blood films

❏ investigation into factors affecting the growth of pollen grains

❏ observations of an insect testis squash

❏ The use of simple respirometers

The use of a respirometer is described in Exchange and Transport, Energy and Ecosystems.As an alternative to using a respirometer containing potassium hydroxide solution, studentscould use a simple respirometer to measure the production of carbon dioxide by yeast duringanaerobic respiration. For the initial experiment, add 2 g of dried yeast to 200 cm3 of 0.2 molper dm3 glucose solution, mix, then measure 25 cm3 into one of the respirometer tubes. Anequal volume of water is then placed in the compensating tube.


• Investigate the effect of temperature on the rate of respiration of yeast.

• Investigate the effect of substrate concentration on the rate of respiration of yeast.

• Investigate the rate of respiration of yeast using a range of different carbohydrates,such as fructose, galactose, glucose, lactose, maltose, raffinose, and sucrose.

Reference

Suggestions for practical investigations with fermenters, including simple methodsfor comparing rates of respiration are included in Practical Fermentation - a guidefor schools and colleges, by John Schollar and Benedikte Watmore (1999) which isavailable from the National Centre for Biotechnology Education.


❏ Demonstration and measurement of transpiration, stomatal counts

The use of a potometer to investigate transpiration is described in Tools, Techniques andAssessment in Biology, and methods for stomatal counts are given in Exchange andTransport, Energy and Ecosystems. As an alternative to the use of a capillary tube potometeras described, students could use a weighing method to investigate transpiration. For longer-term investigations, datalogging could be used to investigate changes in mass, due mainly towater loss, using an electronic balance and software such as Datamass PRO (Philip HarrisEducation).

Stomata on some leaves, such as those of Tradescantia, can be observed directly, usingtransmitted light and a × 10 or × 40 objective lens.


• Relate transpiration to the leaf surface area and express the rate of transpirationquantitatively in terms of mass of water lost per unit leaf area per unit time.

• Investigate differences in stomatal densities between the white and green areas ofvariegated leaves, or between sun and shade leaves of, for example, Dog�s Mercury(Mercurialis perennis).

• Compare stomatal densities on the lower epidermis of two or more different species offlowering plants.

• Investigate factors affecting stomatal opening. Stomatal aperture is influenced byseveral factors including light intensity and carbon dioxide concentration. Toinvestigate the effect of carbon dioxide on stomatal opening, enclose a Tradescantiaplant in a polythene bag containing soda-lime, and keep well-illuminated for aboutthree hours. The stomata should open in response to the reduced concentration ofcarbon dioxide and the increased humidity. Examine a leaf directly with a microscopeand record the percentage of stomata which are open. Compare with an untreatedcontrol plant.

• To investigate the effect of potassium ion concentration on stomatal opening, cutstrips about 5 mm × 10 mm from healthy leaves of Tradescantia and float, lowerepidermis down, in Petri dishes containing the appropriate solutions. Keep the disheswell-illuminated and at about 20 °C. Record the percentage of open stomata byremoving the leaf sections and observing directly with a microscope. Potassiumchloride solutions of 50, 100, 150, 200 and 250 mmol dm-3 are suggested. Theresponses to potassium chloride are variable unless all the stomata are closed beforeeach experiment. Plants should be pre-treated by keeping them in the dark and in ahigh carbon dioxide concentration (15 to 30 per cent) for thirty minutes.

• Students could also use a calibrated eyepiece graticule to measure the mean stomatalapertures in these investigations.


Datamass PRO

Investigating transpiration using the weighing method and datalogging

A well-watered potted plant.The pot should be enclosed ina polythene bag, tied carefullyaround the stem.

Electronic balancewith RS232 output


❏ Microscopic examination of stained blood films

An oil immersion objective (× 100) is recommended for the examination of blood cells, but ifthis not available, a × 40 objective will suffice. When using an oil immersion objective, placeone drop of immersion oil directly onto the slide beneath the lens and carefully lower theobjective until it touches the oil. Focus carefully until the cells are sharply in focus. Afteruse, wipe oil from the lens and slide using a lens tissue. Prepared, stained human bloodsmears are available from Philip Harris Education.

❏ Investigation into factors affecting the growth of pollen grains

A method for investigating germination of pollen grains is included in Applied Plant andAnimal Biology. Pollen grains are suspended in a sucrose solution, such as 0.2 mol per dm3

containing 0.01 g per dm3 boric acid (trioxoboric (III) acid). Pollen grains are then observedin a hanging drop preparation.

A hanging drop preparation to investigate the growth of pollen grains


• Investigate the growth of pollen grains in sucrose solutions of differentconcentrations, such as 0.2, 0.3 0.4 and 0.5 mol per dm3, with and without boric acid.

• Investigate the effect of different concentrations of boric acid on the germination ofpollen grains. Concentrations of boric acid between 0.001 and 0.01 per cent could beused.

• Measure the rate of growth of pollen tubes, using a calibrated eyepiece graticule andmeasuring the length of the pollen tubes every 30 minutes for three hours.

❏ Observations of an insect testis squash

Students could make their own preparations by dissecting testes from locusts and stainingwith aceto-orcein. Locust and grasshopper testis squash preparations are available fromPhilip Harris Education.

Drop of sucrose solutioncontaining pollen grainsCoverslip

Plasticine ringMicroscope slide


Unit 2H Exchange, transport and reproduction in humans


❏ estimation of vital capacity

❏ variation in breathing rates with physical activity

❏ quantitative comparisons of inspired and expired air

❏ effects of physical activity on pulse rate

❏ examination of stained blood films and identification of cells

❏ microscopic examination of the histology of ovary and testis

❏ Estimation of vital capacity

A simple method for the estimation of vital capacity is described in Exchange and Transport,Energy and Ecosystems. Lung volume bags, supplied by Griffin Education and PhilipHarris Education, make suitable alternatives.


• Investigate variations in vital capacity in individuals of the same age.

• Investigate the relationship between vital capacity and body mass or height.

• Compare vital capacities of males and females.

❏ Variation in breathing rates with physical activity

In principle this is a simple investigation but students should consider carefully how toquantify physical activity, such as using a step test, or a fixed number of sit-ups in a giventime. Breathing rate can be measured by direct observation.

❏ Quantitative comparisons of inspired and expired air

This practical involves the use of a gas burette to measure changes in gas volume. Theprinciple of this investigation is that potassium hydroxide solution is used to absorb carbondioxide, this is followed by the use of alkaline pyrogallol (benzene-1,2,3-triol plus potassiumhydroxide) to absorb the remaining oxygen (alkaline pyrogallol absorbs both carbon dioxide


and oxygen so is used after the potassium hydroxide solution). The reductions in gasvolumes, following addition of these reagents, are then used to calculate the percentages ofcarbon dioxide and oxygen. Both alkaline pyrogallol and potassium hydroxide must behandled with great care as they are CORROSIVE.

Materials

# Large plastic bowl filled with cold water# Gas burette# Syringe with needle# Potassium hydroxide solution [add 50 cm3 of tap water to

about 100 g of potassium hydroxide pellets in a Pyrex flask.Cool the mixture by swirling under a tap]

# Alkaline pyrogallol.

Gas burettes, potassium hydroxide and alkaline pyrogallol are available from Philip HarrisEducation.

Using a gas burette to analyse a sample of air

CORROSIVEPotassium hydroxideAlkaline pyrogallol

Gas burette

Suba-seal stopper

Syringe to inject potassiumhydroxide solution, or alkalinepyrogallol


The method for analysis of expired air is shown below.

Step 3

Carefully inject about 0.5 cm3

of potassium hydroxidesolution through the stopper,whilst holding the buretteunder water.

Keeping the burette underwater, rock it carefully to mixthe air and potassiumhydroxide solution.

Step 1

To obtain a sample of expiredair, remove the suba-sealstopper from a clean gasburette and breathe out steadilythrough the tap, into theburette. Whilst continuing tobreathe out, submerge the openend of the burette under waterin the bowl. When you havebreathed out as far as possible,allow a few cm3 of water toflow into the burette from thebowl.

Close the tap and replace thestopper, keeping the end of theburette under water.

Step 2

Leave the burette completelysubmerged in the bowl of waterfor 5 minutes, to allow the airsample to reach the sametemperature as the water.

Hold the burette so that thelevel of water inside andoutside are about the same,then open the tap. Carefullyraise or lower the burette untilthe two water levels are thesame again, then close the tap.

Raise the burette to eye level,read and record the volume ofgas in the burette. This is theINITIAL VOLUME.

Step 6

To obtain a sample ofatmospheric air, fill a gasburette with cold water. Openthe tap and allow about 10 cm3

of water to run out.

Close the tap and immediatelyreplace the suba-seal stopper.

To analyse this air sample,proceed from Step 2.

Step 4

After at least 5 minutes, levelthe solution in the burette withthe water in the bowl, asdescribed in Step 2.

Read and record the volume ofgas in the burette.

Step 5

Repeat Steps 3 and 4, but thistime injecting 0.5 cm3 ofalkaline pyrogallol.

Again, read and record thevolume of gas in the burette.


Record results as follows:

Percentage of carbon dioxide

Gas burette reading Volume / cm3

Initial gas volume[after Step 2]

Volume after adding potassium hydroxide[after Step 4]

Difference in volume

Percentage of carbon dioxide = (difference in volume ÷ initial volume) × 100

Percentage of oxygen

Gas burette reading Volume / cm3

Volume after adding potassium hydroxide[after Step 4]

Volume after adding alkaline pyrogallol[after Step 5]

Difference in volume

Percentage of oxygen = (difference in volume ÷ initial volume) × 100

Note When analysing atmospheric air, the change in volume after the addition ofpotassium hydroxide solution may be insignificant.



• Investigate the mean values for the percentages of oxygen and carbon dioxide insamples of atmospheric air and in expired air.

• Investigate the effect of exercise on the composition of expired air.

❏ The effects of physical activity on pulse rate

Pulse rates may be readily recorded by placing the index and third fingers over the radialartery in the wrist. There are a number of digital pulse recorders available, such as�wristwatch� style pulse monitors, which can be used to record pulse rates during exercise.


• Investigate variations in resting pulse rates in different age groups.

• Measure and record changes in pulse rates in response to varying intensities ofworkload, such as a step test or bicycle ergometer.

• Investigate differences in pulse rates between students who exercise regularly andthose who do not.

Digital pulse monitors are available from Philip Harris Education.

❏ Examination of stained blood films and identification of cells

An oil immersion objective (× 100) is recommended for the examination of blood cells, but ifthis not available, a × 40 objective will suffice. When using an oil immersion objective, placeone drop of immersion oil directly onto the slide beneath the lens and carefully lower theobjective until it touches the oil. Focus carefully until the cells are sharply in focus. Afteruse, wipe oil from the lens and slide using a lens tissue. Prepared, stained human bloodsmears are available from Philip Harris Education.

❏ Microscopic examination of the histology of ovary and testis

Prepared microscope slides are available from Philip Harris Education, of transversesections of ovary and testis. Students may find it helpful to interpret the histology by usingtextbook diagrams and photomicrographs, such as those in the Colour Atlas of Histology,P.R. Wheater, H.G. Burkitt, and P. Lancaster, Longman, ISBN 0 582 35269 X.


Unit 3 Energy and the environment


❏ estimation of pyramids of numbers and of fresh biomass using simpletechniques for the collection and determination of fresh biomass

❏ Estimation of pyramids of numbers and of fresh biomass

Details of the method for estimation of pyramids of numbers and of biomass are given inExchange and Transport, Energy and Ecosystems. Further details of ecological samplingtechniques, and construction of ecological pyramids, are included in Tools, Techniques andAssessment in Biology.


• Compare two different habitats, such as open grassland and leaf litter in a deciduous woodland.

• Compare two different areas within an aquatic habitat.

• Investigate seasonal variation in numbers or biomass of trophic levels in one habitat.


Further Suggestions for Individual Investigations

Factors affecting the activity of milk-clotting enzymes

Introduction

The manufacture of cheese involves the use of enzymes which coagulate milk proteins toform insoluble curds. Traditionally, this involved the use of rennet, extracted from thestomach of calves or other young mammals. One of the enzymes in rennet is chymosin(previously called rennin), which removes surface glycopeptides from the soluble calciumcaseinate particles in milk and causes them to precipitate as insoluble calcium paracaseinate,as illustrated below. There are a number of rennet substitutes, such as those produced byfungi and genetically modified microorganisms, which are used in the manufacture ofvegetarian cheese.

soluble calciumcaseinate particlesin milk

chymosin removes glycopeptides fromthe surface

the casein particles arenegatively charged andunstable

Ca2+ ions help the caseinparticles to clump together

insoluble calcium paracaseinateparticles form the �curds�

The action of chymosin on milk protein - converting casein to curds


Materials required

• Thermostatic water bath, or beaker, tripod, gauze and bunsen burner

• Thermometers

• Syringes or graduated pipettes

• Test tubes or boiling tubes

• Stop clocks or stopwatches

• Pasteurised milk

• Essence of rennet

• Distilled or deionised water

• Rennet substitutes, such as VegeRen, Fromase, or Maxiren

• Calcium chloride solution, 0.01 mol per dm3

• Citric acid solution, 1.0 mol per dm3 (1 cm3 addedto 10 cm3 of milk gives a pH of about 5)

• Sodium hydrogencarbonate solution, 1.0 mol per dm3

(1 cm3 added to 10 cm3 of milk gives a pH of about 8)

• pH indicator paper or pH meter

Planning and carrying out the investigation

Students could investigate the effects of factors such as:

� temperature� enzyme concentration� the presence of calcium ions� pH

Suppliers

Essence of rennet is available from some chemistsand supermarkets

VegeRen is supplied by some health food shops

Fromase and Maxiren are supplied by theNational Centre for Biotechnology Education

IRRITANTCitric acid


It is essential that each student plans and carries out their investigation individually, althoughgroups of students may be investigating a similar broad topic, such as this chymosin example.They should be given the opportunity to carry out a simple pilot experiment to determine, forexample, appropriate volumes and concentrations to use in their investigation. Students willalso need to consider how to determine the end point of their reactions, such as appearance ofgranules in the milk, partial or full setting of the milk.

It is expected that the investigation will take about three hours of practical time, andstudents should be guided into devising an investigation which is likely to give meaningfulresults and can be carried out using the resources available.

Past experience has shown that high-scoring investigations:

! have one, straightforward, testable hypothesis

! have detailed plans which consider how all the important variables are to be controlledand how safety requirements are to be met

! consider interesting questions rather than repeating standard �textbook� experiments

! give students opportunities to vary their own methods and display and analyse their data inan individual way

! have short pilot experiments to establish a workable and reliable method

! show clear progression from GCSE coursework

! limit the use of biological theory to that which is relevant to the hypothesis being tested

! pay careful attention to the use of SI units in all tabulation and data presentation

! display data in an appropriate format which aids analysis of results

! analyse the limitations of the techniques used rather than suggesting practicalincompetence in using simple apparatus


Allocation of marks for the individual investigation

Planning 8 marks

Implementing 8 marks

Analysing evidence and drawing conclusions 8 marks

Evaluating evidence and procedures 8 marks

Total 32 marks

Scheme of practical assessment

Details of the scheme of practical assessment andcriteria for marking are included in theSpecifications [Edexcel Advanced Subsidiary GCEin Biology 8040 and Biology (Human) 8042]


References

Adds J, Larkcom E and Miller R Molecules and Cells Nelson (2000)ISBN 017�448-293-0 [Unit 1]

Adds J, Larkcom E and Miller R Exchange and Transport, Energy and Ecosystems Nelson(2000)ISBN 017�448�294-9 [Units 2 and 3]

Adds J, Larkcom E, Miller R and Sutton R Tools, Techniques and Assessment in Biology:A Course Guide for Students and Teachers Nelson (1999) ISBN 017-448-273-6

Adds J, Larkcom E and Miller R Applied Plant and Animal Biology Nelson (1999) ISBN 017�448-270-1

Practical Biotechnology - a guide for schools and colleges, available from the NationalCentre for Biotechnology Education or from the NCBE website as pdf files (free of charge) or£5 for the printed version while stocks last.

Schollar J and Watmore B Practical Fermentation - a guide for schools and colleges,published by the Society for General Microbiology 1999 ISBN 0 9536838 0 X, available fromthe National Centre for Biotechnology Education

Wheater PR, Burkitt HG and Lancaster P Colour Atlas of Histology Longman ISBN 0 58235269 X

Useful addresses

Edexcel Foundation, Stewart House, 32 Russell Square, London, WC1B 5DN, UK.Tel: +44 (0) 20 7393 4444; http://www.edexcel.org.uk

Griffin Education, Bishop Meadow Road, Loughborough, Leicestershire, LE11 3RG, UK.Tel: +44 (0) 1509 233344; http://www.fisher.co.uk

National Centre for Biotechnology Education, School of Animal and Microbial Sciences,The University of Reading, Whiteknights, Reading, RG6 6AJ, UK.Tel: +44 (0) 118 9873743; http://www.reading.ac.uk/NCBE

Philip Harris Education, Lynn Lane, Shenstone, Lichfield, Staffs, WS14 0EE, UK.Tel: +44 (0) 1543 480077; http://www.philipharris.co.uk/education


BOOKLIST AND RESOURCE SUGGESTIONS

These suggestions support the Edexcel Biology and Biology (Human) Advanced Subsidiaryand Advanced GCE specifications. They are intended primarily for teachers of thespecifications: intending candidates should consult their teachers or tutors regarding suitablebooks. The resources and books included should be treated as suggestions rather thanessential recommendations or an exhaustive list. Teachers who know of relevant publicationswhich are not listed are invited to inform the Subject Leader for Biology at Edexcel so thatthey may be included in future revisions.

Where possible, the date of the latest edition of the book is given, and whilst attempts havebeen made to ensure accuracy of the information there is no guarantee that this is the case.Similarly, Edexcel is not responsible for the accuracy of material contained in any of thepublications listed.

The publishers Nelson Thornes are collaborating with Edexcel to provide a series ofsupporting texts linked specifically to the Units in the Edexcel Biology and Biology (Human)AS and Advanced GCE specifications. They are:

Adds J, Larkcom E and Miller R Molecules and Cells (2000) ISBN 017 448 2930 [Unit 1]

Adds J, Larkcom E and Miller R Exchange and Transport, Energy and Ecosystems (2000)ISBN 017 448 2949 [Units 2B/2H and 3]

Adds J, Larkcom E and Miller R Respiration and Co-ordination (with Options) (due 2001)ISBN 017 448 2957 [Unit 4]

Adds J, Larkcom E and Miller R Genetics, Evolution and Biodiversity (due 2001) ISBN 017448 2965 [Units 5B/5H]

Adds J, Larkcom E, Miller R and Sutton R Tools, Techniques and Assessment in Biology; ACourse Guide for Students and Teachers (2000) ISBN 017 448 2736

Adds J, Larkcom E, Miller R, Clamp A, and Furness-Smith M Make the Grade in AS Biologyand Human Biology (due 2000) ISBN 017 448 2795

Adds J, Larkcom E, Miller R, Clamp A, and Furness-Smith M Make the Grade in AdvancedGCE Biology and Human Biology (due 2001) ISBN 017 448 3090

For teachers who already possess the texts in the Nelson Modular Advanced Science serieswhich support the Edexcel Biology and Human Biology GCE AS and A Level Syllabus, amapping document is available elsewhere in this Teachers� Guide to reference material inthe Edexcel Biology and Biology (Human) AS and Advanced GCE specifications.


The following books are also specific to the Edexcel specification:

Jones G and Jones M Energy and the Environment Collins (2000) ISBN 000 327714 3

Jones G and Jones M Molecules and Cells Collins (2000) ISBN 000 327712 7

Jones G and Jones M Exchange, Transport and Reproduction Collins (2000) ISBN 000327713 5

GENERAL

Aldridge S Biochemistry for Advanced Biology Cambridge University Press (1994) ISBN 0521 437814

Applin D Medical Physiology: Advanced Biology Topics Cambridge University Press (1997)ISBN 0521 55661 9

Barbor M, Boyle M, Cassidy M, and Senior K Collins Advanced Science: Biology CollinsEducational (1997) ISBN 0 00 322327 2

Biological Nomenclature:Standard terms and expressions used in the teaching of biology 3rdEdition (2000) available from The Institute of Biology www.iob.org

Boyle M, Indge B and Senior K Collins Advanced Science: Human BiologyCollins (1999) ISBN 000 329095 6

Chapman J and Reiss M Ecology Principles and Applications Cambridge University Press(1998) ISBN 0 521 58802 2

Chenn P Ecology: Advanced Biology Readers John Murray (1998) ISBN 07195 75109

Clamp A AS/A Level Biology Essential Words Dictionary Philip Allan ISBN 0860033724

Clegg CJ and Mackean DG Advanced Biology: Principles and Applications John Murray(2000) ISBN 0 7195 767 09

Clegg CJ Illustrated Advanced Biology Genetics and Evolution John Murray (1999) ISBN 07195 7552 4

Clegg CJ Introduction to Advanced Biology John Murray (due 2000) ISBN 0 7195 76717

Fullick A Advanced Science Biology Heinemann (2000) ISBN 435 570951

Hall DO and Rao K Photosynthesis: Studies in Biology Cambridge University Press (1999)ISBN 0521644976

http://www.iob.org/


Green NPO, Stout GW and Taylor DJ Biological Science, Volumes 1 and 2 CambridgeUniversity Press (1997) ISBN 0 521 56178 7

Indge B The Complete A-Z Biology Handbook Hodder and Stoughton (2000) ISBN0340772212

Jones M and Jones G Advanced Biology Cambridge University Press (1997) ISBN 0 52148473 1

Lawrence E Henderson�s Dictionary of Biological Terms Longman (1999) ISBN 0582414989

Roberts MBV Biology: Principles and Processes Nelson (1996) ISBN 017544000X

Simpkins J and Williams JI Advanced Human Biology Collins (1995) ISBN 000 322290X

Toole G and Toole S Advanced Human and Social Biology Stanley Thornes (1997) ISBN 07487 2911 9

Toole G and Toole S New Understanding Biology for Advanced Level Nelson Thornes (2000)ISBN 0 7487 3957 2

Toole G and Toole S Biology for Advanced Level: Course Study Guide Nelson Thornes(2000) ISBN 0 7487 3963 7

Williams G Advanced Biology for You Nelson Thornes (2000) ISBN 0 7487 5298 6

PRACTICAL

Adds J, Larkcom E, Miller R and Sutton R Tools, Techniques and Assessment in Biology: ACourse Guide for Students and Teachers Nelson Thornes (2000) ISBN 017 448 2736

Aldridge S Practical Biochemistry for Advanced Biology Cambridge University Press (1994)ISBN 0521 43782 2

Clegg CJ, Mackean DG, Reynolds R and Openshaw P Advanced Biology Study Guide JohnMurray (1996) ISBN 07195 5358 X

Jones A, Reed R and Weyers J Practical Skills in Biology Longman (1998) ISBN0582298857

Reed R, Holmes D, Weyers J and Jones A Practical Skills in Biomolecular SciencesLongman (1998) ISBN 0582 298261

Roberts MBV, Reiss MJ and King TJ Practical Biology for Advanced Level Nelson (1994)ISBN 0 17 448225 6


OPTIONS

Microbiology and Biotechnology, Food Science, Human Health and Fitness

Acheson D Dietary Reference Values for Food Energy and Nutrients for the United KingdomThe Stationery Office (1991) ISBN 011 3213 972

Adds J, Larkcom E and Miller R Respiration and Co-ordination (with Options) NelsonThornes (due 2001) ISBN 017 448 2957

Adds J, Larkcom E and Miller R Microorganisms and Biotechnology Nelson (1998) ISBN017 448 2269 8

Adds J, Larkcom E and Miller R Food and Health Nelson (1998) ISBN 01744822728

Beashel P and Taylor K Advanced Studies in Physical Education and Sport Nelson (1996)ISBN 0174482345

Brooks GA and Fahey TD Exercise Physiology (Human Bioenergetics and Its� Applications)Houghton Mifflin (Mayfield) (1996) ISBN 1559343656

Chenn P Microorganisms and Biotechnology: Advanced Biology Readers John Murray(1997) ISBN 0 7195 75095

Clegg C Exercise Physiology and Functional Anatomy Feltham Press (1995) ISBN0952074311

Davis B, Bull R, Roscoe J and Roscoe D Physical Education and the Study of Sport Mosby(1996) ISBN 0723426422

Fox B and Cameron A Food Science, Nutrition and Health Arnold (1995) ISBN 0340604832

Fullick A Advanced Science: Human Health and Disease Heinemann (1998) ISBN 43570919

Heritage J, Evans G and Killington D Introductory Microbiology: Studies in BiologyCambridge University Press (1996) ISBN 0521 44977 4

Heritage J, Evans G and Killington D Microbiology in Action: Studies in Biology CambridgeUniversity Press (1999) ISBN 0521 629128

MAFF (Ministry of Agriculture Fisheries and Food) The Manual of Nutrition The StationeryOffice (1995) ISBN 011 242 9912

National Centre for Biotechnology Education Practical Biotechnology: A guide for schoolsand colleges from the NCBE website as pdf files http://www.reading.ac.uk/ncbe


Schollar J and Watmore B Practical Fermentation: A guide for schools and colleges NationalCentre for Biotechnology Education ISBN 0 9536038 0 X (Teachers's guide and student'sguide available as pack containing two Teacher's Guides and five Student's Guides)

Smith JE Biotechnology; Studies in Biology Cambridge University Press ( 1997 ) ISBN 052144911 1

Truswell S ABC of Nutrition BMJ Books (1999) ISBN 07279 03152

Walker A Applied Human Nutrition Cambridge University Press (1990) ISBN 0747 600627

MATHS AND STATISTICS

Cadogan A and Sutton R Maths for Advanced Biology Nelson (1994) ISBN 017 448 2140

Edmonson A and Druce D Advanced Biology Statistics Oxford University Press (1996) ISBN019 9146543

Fowler J and Cohen L Practical Statistics for Field Biology John Wiley (1998) ISBN0471982962

USEFUL ADDRESSES, WEBSITES AND JOURNALS

BASC (Biochemistry Across the School Curriculum Series) Biochemical Society c/o PortlandPress Ltd, Commerce Way, Colchester, Essex CO2 8HP www.biochemsoc.org.uk

The Biologist, Journal of Biological Education, The Institute of Biology, 20 QueensberryPlace, London SW7 1ZY www.iob.org

Biotechnology and Biological Sciences Research Council (BBSRC) Polaris House, NorthStar Avenue, Swindon SN2 1UH www.bbsrc.ac.uk

Biological Sciences Review published by Philip Allan, Market Place, Deddington, OxfordOX 5 4SE www.philipallan.co.uk

British Nutrition Foundation, High Holborn House, 52-54 High Holborn, London WC1V6RG www.nutrition.org.uk

The CLEAPSS ( Consortium of Local education Authorities for the Provision of SchoolServices) Laboratory Handbook from The CLEAPPS School Science Service, BrunelUniversity, Uxbridge UB8 3PH www.cleapss.org.uk

The European Food Information Council (EUFIC) www.eufic.orgInformation about food related issues and the nutritional quality and safety of food.

http://www.biochemsoc.org.uk/

http://www.iob.org/

http://www.bbsrc.ac.uk/

http://www.philipallan.co.uk/

http://www.nutrition.org.uk/

http://www.cleapss.org.uk/

http://www.eufic.org/


The European Initiative for Biotechnology Education www.rdg.ac.uk/eibeTeaching resources for 16-19 year olds: units containing opportunities for debates etc.

EU Nature Conservation Homepage http://europa.eu.int/comm/environment/nature/home/htmInformation concerning environmental legislation, EU Habitats Directive and Natura 2000network.

Field Studies Council, Preston Montfort, Montfort Bridge, Shrewsbury Shropshire SY4 1HWwww.field-studies-council.org

National Centre for Biotechnology Education (NCBE) at the University of Reading,Whiteknights, Reading RG6 6AJ www.reading.ac.uk/ncbeResources including enzymes, cultures of microorganisms, fermenters, kits for DNAelectrophoresis etc.

New Scientist published by IPC Magazines Ltd, King Reach Tower, Stanford Street, London.Also available on CD-ROM and www.newscientist.com

Royal Institution of Great Britain, 21 Albemarle Street, London W1 www.ri.ac.ukSchool lectures, practical demonstrations and advice, and publications.

School Science Review published by The Association for Science Education, College Lane,Hatfield Herts AL 10 9AA www.ase.org.uk

Science and Plants for Schools (SAPS) Head Office, Homerton College, Cambridge CB22PH www-saps.plantsci.cam.ac.uk

The Wellcome Trust,183,Euston Road, London NW1 2BE www.wellcome.ac.ukResources, practical activities, publications and information on the latest research inbiomedical science.

http://www.rdg.ac.uk/eibe

http://europa.eu.int/comm/environment/nature/home/htm

http://www.field-studies-council.org/

http://www.reading.ac.uk/ncbe

http://www.newscientist.com/

http://www.ri.ac.uk/

http://www.ase.org.uk/

http://www.wellcome.ac.uk/


GLOSSARY OF TERMS USED IN EXAMINATION QUESTIONS

Examination questions are very carefully worded in order that they elicit the responseintended by the examiners. It is therefore important that candidates are able to identify andrespond appropriately to the key words in questions which will guide them in selecting theanswer required.

name, state, give �indicate that short, factual answers are needed, possibly with precise use of biological termsor the name of a structure. Often one word answers are sufficient.

compare, contrast, distinguish between, differs from �here there will be two (or more) sets of data, structures, functions, processes or events to bereferred to and the answer must relate to both. It is important to select equivalent points andto keep them together.compare generally indicates that similarities as well as differences are expected, contrast,distinguish between or differs from indicate that the focus should be on the differences.

advantages, disadvantages �as with comparisons or differences, these questions require one process or whatever to becompared with another. It is important that the answers are comparative and that the featurebeing referred to is clearly stated.

describe �this may be related to a biological event or process, or to data presented in a table, graph orother form. The description must be concise and straightforward, using relevant biologicalterms rather than vague generalisations. The trend should be presented in words or translatedinto another form. If interpreting numerical data, it is often appropriate to refer to the figures,and these should be 'manipulated' in some way, for instance, the trend could be quantified orthe percentage difference over a period of time calculated.

explain, give explanations, give reasons �the answer would be expected to draw on biological knowledge to give reasons orexplanations for the information or data given. Usually 2- or 3- mark answers are requiredand the answer should go beyond just repetition or reorganisation of the information or datapresented. Candidates should check that their response answers the question "Why.....?"

using the information in the diagram/ in the table/ on the graph/ features visible in thediagram �make sure the answer refers only to the information presented in the question and not to otherexamples or features, which may be perfectly correct, but are not shown and are therefore notwhat the examiners require.

suggest �implies that the answer may include material or ideas which have not been learnt directlyfrom the specification. A reasonable suggestion, using biological knowledge andunderstanding of related topics is required.


THE MAPPING DOCUMENT

This document enables users of the texts in the Nelson Advanced Science Series, whichsupport the Edexcel Biology and Human Biology GCE AS and A Level Syllabus, to referencematerial in the Curriculum 2000 Edexcel Biology and Biology (Human) AS and AdvancedGCE specifications.

The Nelson Advanced Science Series texts referred to are;

Adds J, Larkcom E and Miller R Cell Biology and Genetics Nelson (1996) ISBN 017 448 2663

Adds J, Larkcom E and Miller R The Organism and the Environment Nelson (1997) ISBN017 448 274 4

Adds J, Larkcom E and Miller R Systems and their Maintenance Nelson (1999) ISBN 017448 2268 X

Adds J, Larkcom E and Miller R Plant and Animal Biology Nelson (1999) ISBN 017 4482701

Adds J, Larkcom E and Miller R Microorganisms and Biotechnology Nelson (1998) ISBN017 448 2269 8

Adds J, Larkcom E and Miller R Food and Health Nelson (1998) ISBN 01744822728

Unit 1: Molecules and cells

Topic1.1 Molecules Cell Biology and Genetics

Water Chapter 2Carbohydrates [but lacks specific references to insulin structureLipids and collagen structure] ProteinsNucleic acids Chapter 5 pp 56 to 66

For replication of DNAnature of the genetic codeprotein synthesis

1.2 Enzymes Cell Biology and GeneticsChapter 5but lacks details of the commercial uses of enzymes/pectinases/proteases/lactase immobilisationPractical work is different.


1.3 Cellular organisation Cell Biology and GeneticsProkaryotic cells Chapter 1Eukaryotic cellsTransport across membranesAggregations of cellsFor practical work on microscopy see Tools, Techniques and Assessment

1.4 The cell cycle Cell Biology and GeneticsChromosome structure Chapter 5Mitosis

Not much on natural and artificial cloningsee Asexual reproduction section inSystems and their MaintenanceChapter 6 pp 113 to 116

Unit 2B: Exchange, transport and reproduction

Topic2B.1 Exchanges with the Systems and their Maintenance

environment Chapter 1Exchange processesGas exchange in protozoa not much on gas exchange in protozoaGas exchange in floweringplantsGas exchange in humans

Do not need gas exchange in insects or kidney hereDigestion and absorption The Organism and the Environment

Chapter 2

2B.2 Transport systems Systems and their MaintenanceTransport in Chapter 2flowering plantsMovement of water [bit on water relations of plant cells in

The Organism and the Environment Chapter 3 pp 45 to 50]

Movement of nutrientsTransport in mammalsBlood and body fluids

2B.3 Adaptation to The Organism and the Environmentthe environment Chapter 4Structural adaptation [a bit about oxygen concentration and freshwater

organisms; water availability and xeromorphic plants]This section is not really covered in the original texts.


2B.4 Sexual reproduction Systems and their MaintenanceReproduction in Chapter 6 from p 116 seq.flowering plants [need Meiosis from Cell Biology and GeneticsReproduction in humans Chapter 5 pp 72 to 77]

Unit 2H: Exchange, transport and reproduction in humans

Topic2H.1 Exchanges with the Systems and their Maintenance

environment Chapter 1Exchange surfaces [but not gas exchange in flowering plants]BreathingGas exchangeDigestion and absorption The Organism and the Environment

Chapter 2 pp 27 to 36

2H.2 Transport of materials Systems and their MaintenanceCirculation Chapter 2 pp 37 to 49The circulatory systemBlood and body fluids

2H.3 Human Ecology The Organism and the EnvironmentAdaptations to extreme Chapter 10environmentsExtremes of temperatureHigh altitude

[circadian rhythms not required]

2H.4 Human reproduction Systems and their Maintenanceand development Chapter 6 pp 128 to 140Reproduction [need Meiosis from Cell Biology and GeneticsDevelopment Chapter 5 pp 72 to 77]

[control of fertility not required]

Unit 3: Energy and the Environment

Topic3.1 Modes of nutrition The Organism and the Environment

Autotrophic and Chapter 2heterotrophic nutrition [but adaptations of carnivores and herbivores withHolozoic nutrition reference to named examples not covered: someSaprobiontic and information on herbivores inparasitic nutrition Applied Plant and Animal Biology]Mutualistic nutrition


3.2 Ecosystems The Organism and the EnvironmentChapter 5

3.3 Energy flow The Organism and the EnvironmentChapter 5 pp 87 to 93

3.4 Recycling of nutrients The Organism and the EnvironmentChapter 5 pp 94 to 95Water cycle p 62Carbon cycle p 140

3.5 Energy resources The Organism and the EnvironmentChapter 6 pp 106 to 112

3.6 Human influences on The Organism and the Environmentthe environment Chapter 6 for deforestation and desertification

Chapter 7 for atmospheric pollution and water pollution

Unit 4: Respiration and coordination and OptionsTopic4.1 Metabolic pathways Cell Biology and Genetics

Cellular respiration Chapter 4Aerobic respirationAnaerobic respiration

4.2 Regulation of the Systems and their Maintenanceinternal environmentMammalian kidney Chapter 1 [Nitrogenous excretion in mammals]Regulation of blood glucose Chapter 3 pp 67 to 71Response to changes in the Chapter 3 pp 62 to 67; Chapter 4 pp 82 to 85external environmentChemical coordination in Chapter 3, but ADH Chapter 1 pp 19 to 20animals Chapter 6 for reproductive hormonesNervous coordination in Chapter 4mammalsThe central nervous system Chapter 4

Option A: Microbiology and biotechnology covered by present text.

Option B: Food science covered by Food and Health

Option C: Human health and fitness - parts of this Option are based on the humanphysiology in the specification, extending and expanding some of the topics; parts e.g.musclestructure, were in the old syllabus but have gone from the new specification and there are newtopics covering exercise physiology and human disorders. It will be covered fully in the newUnit 4 text.


Unit 5B: Genetics, evolution and biodiversity

Topic5B.1 Photosynthesis The Organism and the Environment

Leaf structure Chapter 1Light-dependent reaction [not C3 and C4 plants]Light-independent reactionEnvironmental factorsaffecting photosynthesisMineral nutrition

5B.2 Control of growth in Systems and their Maintenanceplants Chapter 3 pp 54 to 67

5B.3 Biodiversity The Organism and the EnvironmentClassification Chapter 4 pp 55 to 59Distribution of plants and Chapter 4 pp 60 to 71animalsSuccession Chapter 4 pp 71 to 76Populations Chapter 5 pp 80 to 87

Control of insect populations Chapter 7 pp 127 to 135Conservation Chapter 6 pp 112 to 124

5B4. Genetics and evolution Cell Biology and GeneticsVariation Chapter 6Genes and allelesSources of new inherited Chapter 7variationEnvironmental change and The Organism and the Environmentevolution Chapter 8Gene technology Cell Biology and Genetics

Chapter 7[but this section has been expanded to fit the newspecification in the revised texts]

Unit 5H: Genetics, human evolution and biodiversity

Topic5H.1 Genetics and evolution Cell Biology and Genetics

Variation Chapter 6Genes and allelesSources of new inherited Chapter 7variation


Genetic counselling Systems and their MaintenanceChapter 6 pp 145 to 152

Environmental change and The Organism and the Environmentevolution Chapter 8Gene technology Cell Biology and Genetics

Chapter 7[but this section has been expanded to fit the new specification in the revised texts]

5H.2 Human evolution The Organism and the EnvironmentHumans as primates Chapter 9Evidence for humanevolutionHominoid evolutionEvolution of HomoPalaeolithicNeolithic

5H.3 Human populations The Organism and the EnvironmentWorld trends in Chapter 11population sizePopulation structure

5H.4 Biodiversity The Organism and the EnvironmentDistribution of plants and Chapter 4 pp 60 to 71animalsSuccession Chapter 4 pp 71 to 76Control of insect pests Chapter 7 pp 127 to 135Conservation Chapter 6 pp 112 to 124

Further copies of this publication are available fromEdexcel Publications, Adamsway, Mansfield, Notts NG18 4LN

Telephone 01623 467467Fax 01623 450481

Order code: UA007577 Issue 1 July 2000

For more information on Edexcel qualifications please contact ourCustomer Response Centre on 020 7393 4500or email: [email protected] visit our website: www.edexcel.org.uk

© 2000 EDEXCEL FoundationThis publication may only be reproduced in accordance with Edexcel copyright policy.Edexcel Foundation is a registered charity and a company limitedby guarantee. Registered in England No 168164.

mailto:[email protected]

http://www.edexcel.org.uk/

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