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Practise

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2730 questions · page 96 of 137 · choose a topic above to narrow them down

SA-AB-DR-0041 markL2 StandardCalculatorReplication

DNA polymerase joins nucleotides by forming

Salam Academy Original Practice · Proposed mark scheme

SA-AB-DR-0051 markL2 StandardCalculatorEvidence

In Meselson and Stahl's experiment, after one generation in ¹⁴N, all DNA was intermediate density. This ruled out

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SA-AB-EC-0012 marksL2 StandardCalculatorEnergy transfer

GPP = 20 000 kJ m⁻² yr⁻¹ and respiratory loss = 12 000. Calculate NPP.

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SA-AB-EC-0022 marksL2 StandardCalculatorEnergy transfer

Producers have 8000 kJ m⁻² yr⁻¹ available; herbivores gain 800. Calculate the efficiency of transfer (%).

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SA-AB-EC-0041 markL2 StandardCalculatorNutrient cycles

Nitrogen fixation converts

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SA-AB-EC-0051 markL2 StandardCalculatorNutrient cycles

Nitrification is carried out by

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SA-AB-EK-0021 markL2 StandardCalculatorFactors

Above the optimum temperature, rate falls because

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SA-AB-EK-0031 markL2 StandardCalculatorInhibition and Km

A competitive inhibitor

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SA-AB-EK-0041 markL2 StandardCalculatorInhibition and Km

A non-competitive inhibitor

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SA-AB-GE-0021 markL2 StandardCalculatorLungs

Goblet cells in the trachea

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SA-AB-GE-0031 markL2 StandardCalculatorLungs

Cartilage in the trachea

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SA-AB-GE-0041 markL2 StandardCalculatorLungs

Elastic fibres in alveoli

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SA-AB-GE-0051 markL2 StandardCalculatorVentilation

During inspiration,

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SA-AB-GE2-0021 markL2 StandardCalculatorStem cells

Bone marrow stem cells that form different blood cells are

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SA-AB-GE2-0031 markL2 StandardCalculatorStem cells

iPS cells are made by

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SA-AB-GE2-0041 markL2 StandardCalculatorRegulation

A transcription factor

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SA-AB-GE2-0051 markL2 StandardCalculatorRegulation

Oestrogen can enter cells easily because it is

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SA-AB-GT-0021 markL2 StandardCalculatorTools

DNA ligase

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SA-AB-GT-0031 markL2 StandardCalculatorTools

Reverse transcriptase makes

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SA-AB-GT-0041 markL2 StandardCalculatorTools

The same restriction enzyme cuts the gene and plasmid so that

Salam Academy Original Practice · Proposed mark scheme