Metabolism refers to all of the chemical reactions that take place inside living cells. Unicellular and multicellular organisms must control their metabolism in order to survive.
This occurs when an inhibitor molecule binds to the active site of the enzyme and stops the substrate from binding.
They can compete with the substrate because they have a similar molecular shape. Increasing the substrate concentration can reverse competitive inhibition.
This is because the substrate eventually dilutes the inhibitor so that all enzyme molecules bind to the substrate. An example of a competitive inhibitor is sarin.