Explain with two examples how elements functions as activator of enzymes ?

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​Please find below the solution to the asked query    

Molecules that bind to enzyme and increase its activity are known as enzyme activators. 
Example: 1. Ferrous ions when used with the enzyme pectinase show synergistic effect on the formation of rusty-root.
                2. Activity of yeast pyruvate carboxylase is accelerated in presence of magnesium chloride as enzyme activator.

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