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A-LevelBiologyImmunityOct/Nov 2014Paper 1 Q71 Mark

Proteases are a group of enzymes that digest proteins. Which statement about proteases is correct?

Abacterial protease that is secreted from a disease-causing bacterium could act as an antigen and cause the production of an antibody.
BBacterial proteases are important in the nitrogen cycle as they are able to catalyse the breakdown of the organic nitrogen molecules nucleotides and urea.
CNon-competitive inhibition of a protease that has an optimum pH of pH2 can be overcome by increasing the substrate concentration and increasing the pH.
DWater molecules are required when peptide bonds that link the monomers together are broken by the action of proteases in condensation reactions.

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About This A-Level Biology Question

This multiple-choice question appeared in the Cambridge A-Level Biology (9700) Oct/Nov 2014 examination, Paper 1 Variant 2. It tests the topic of Immunity and is worth 1 mark.

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