The flux of the entire pathway is regulated by the rate-determining steps.  : 577–578 These are the slowest steps in a network of reactions. The rate-limiting step occurs near the beginning of the pathway and is regulated by feedback inhibition, which ultimately controls the overall rate of the pathway.  The metabolic pathway in the cell is regulated by covalent or non-covalent modifications. A covalent modification involves an addition or removal of a chemical bond, whereas a non-covalent modification (also known as allosteric regulation) is the binding of the regulator to the enzyme via hydrogen bonds , electrostatic interactions, and Van Der Waals forces . 
Other types of catabolic pathways include the citric or Krebs cycle, where acetate from macronutrients, like protein, fat, and carbohydrate molecules, undergo oxidation. The end result is the chemical compound carbon dioxide. Glycolysis is another type of catabolic pathway, whereby organisms and plants store and release glucose and other sugar energy to make a high-energy molecule known as adenosine triphosphate (ATP). Biologists refer to ATP as the 'energy currency of life' because it stockpiles the energy we need to function and perform on an everyday basis. The process of glycolysis is used to create energy via the catabolic pathway.