A sample is removed from the test tubes every 10 seconds to. Breakdown answer into 5 simple marks that can be easily understood and rememberedControl variable - Keep amount of amylase and starch the sameDependent. Learning By Questions Describe how the student could investigate the effect of pH on the breakdown of starch by amylase. . Amylase is an enzyme that catalyses the hydrolysis of starch into sugars. Answers Biology GCSE Article. As for the starch digestion by AMG EGCG was observed with an obvious inhibition effect from the digestion beginning as suggested by the significantly decreased digestion rate constants k at both the RDS and SDS digestion phases P. The analogy is that the enzyme is the lock and the key is the substrate only the correct key substrate fits into the keyhole active. By doing this in an early stage of the digestive process it eases the work of the pancreas which as well produces amylase. It usual...