Glycolysis is performed by all living organisms and consists of 10 steps.  The net reaction for the overall process of glycolysis is:
:Glucose + 2 NAD+ + 2 P + 2 ADP → 2 pyruvate + 2 ATP + 2 NADH + 2 HO
Steps 1 and 3 require the input of energy derived from the hydrolysis of ATP to ADP and P (inorganic phosphate), whereas steps 7 and 10 require the input of ADP, each yielding ATP.  The enzymes necessary to break down glucose are found in the cytoplasm, the viscous fluid that fills living cells, where the glycolytic reactions take place.