K.C.S.E Biology Q & A - MODEL 1995PP1QN10

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An experiment was carried out to investigate the rate of reaction shown below;
Sucrose →Fructose + Glucose

For the products fructose and glucose to be formed, it was found that substance K was to be added and the temperature maintained at 37⁰C. When another substance L was added, the reaction slowed down and eventually stopped.

• (a) Suggest the identify of substances K and L ( 2 mks)
• (b) Other than temperature state three ways by which the rate of reaction  could  be  increased ( 3 mks)
• (c) Explain how substance L slowed down the reaction ( 2 mks)

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KNEC ANSWERS

​(a)

• K-Enzymes/ Sucrose/ Invertase/ Saccharise     
• L- Inhibitor Acceptance any example e.g. any acid

(b)

• Addition of sucrose/ substrate
• Optimum/ suitable/ correct / right pH
• Removal of products

(c)       

• Competed with substance: for active  site  (of K)
• Acc. L made  the medium acidic; unsuitable for K
• L occupies active sites