Feedback inhibition is a phenomenon in which the final product formed in a metabolic pathway tends to inhibit the enzymes that are involved in it. This happens due to the fact that the product is deposited in the cell to such an extent that the optimum amount of it is reached. There is no more requirement of that product in the cell.
This amount of product is decreased by inhibiting such an enzyme which is responsible for its synthesis. After the inhibition, the product is used up by the cell and its concentration is decreased and the inhibition of the enzyme is relaxed. Hence, it is a mechanism which limits the concentration of cell constituents.
