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#ecall %epeat knowledge from prior learning. #ecognise To identify.#ecord %eport or note.#elate Make interconnections.

$%etch Produce a simple" freehand drawing. + single clear sharp line should )e

used. $n the context of a graph" the general shape of the curve would )e sufficient.

$tate Produce a concise answer with no supporting argument.$uggest+pply your )iological knowledge and understanding to a situation which youmay

not have covered in the specification. $ummarise Present main points in outlineonly.

&se+pply the information provided or apply prior learning. '(

) !C# '*+, -CE .iology

Additional Clarification/

0ow/ 1hat/ 1hy/

Accuracy/

"recision/ #eliability/

2alidity/

&escri)e in what way or )y what means...... Provide specific information......xplain the reason or purpose......

The accuracy of an o)servation" reading or measurement is the degree to which itapproaches a notional /true0 value or outcome. 1or example2 closeness to a line of)est fit3 accuracy of apparatus on percentage error.

The a)ility to )e exact 'degree of precision*.

The measure of confidence that can )e placed in a set of o)servations ormeasurements. 1or example2 confidence limits of statistical tests or concordance ofrepeats or standard deviation.

The implication that the outcome of an activity is not )eing distorted )y extraneousfactors.

%ead the instructions carefully 415% you start the experimentand do exactly asthey say.Common limitations and improvements2 temp was not keptconstant 6 use thermostatically controlled water )athdifficult to test all tu)es at same time intervals 6 do tests one at atime

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no intermediate concentrations 6 use meters e.g. colorimeter orscale(chartonly one sample per test tu)e 6 repeat tests x7 6more likely to findanomalies

no control 6 use pure water etcair )u))les in syringes 6 avoidprecipitate when o)serving colour 6 filtercontamination )etween syringes 6 sterilise e#uipment(use freshonesudgement of end point e.g. when ppt forms(solution thickened 6use colorimeter(do preliminary tests and repeat" viscosity testSie of drops not uniformly same 6 use standard volumes6reduces9 error

&elay )etween adding reactants and starting time 6 use differentapparatus(another person&ifferent species e.g. potatoes 6 use same one!as is lost in experiment affecting volume collected 6 useapparatus that allows to start after sealedincomplete grinding e.g. of seeds to release enymes 6 usemechanical grinder+lso make sure you know the difference )etween accuracy"relia)ility and validity