Question

Role of substrate concentration on enzyme activity

Answer 1

Answer:

Enzymes are catalysts. They are usually proteins, though some RNA molecules act as enzymes too.

Enzymes lower the activation energy of a reaction - that is the required amount of energy needed for a reaction to occur. They do this by binding to a substrate and holding it in a way that allows the reaction to happen more efficiently.The part of the enzyme where the substrate binds is called the active site. Here, the enzyme changes shape slightly, fitting tightly with the substrate and forming the enzyme/substrate complex.

Increasing substrate concentration also increases the rate of reaction to a certain point. Once all of the enzymes have bound, any substrate increase will have no effect on the rate of reaction, as the available enzymes will be saturated and working at their maximum rate.

Increasing enzyme concentration will speed up the reaction, as long as there is substrate available to bind to. Once all of the substrate is bound, the reaction will no longer speed up, since there will be nothing for additional enzymes to bind to.