What product goes into glycolysis and what out comes?
1 Glucose molecule goes into Glycolysis and 2 Pyruvate comes out if oxygen is available, yielding ATP and NADH energy.
One glucose (sugar monomer) molecule enters the cell. Enzymes convert glucose from a ringed structure to a linear one and cut the molecule in half. The end result is two molecules of Pyruvate (pyruvic acid).
If oxygen is NOT available, the Pyruvate molecules are each converted to lactic acid (makes your muscles feel sore). This yields quick but minimal amounts of energy. The reaction is reversible once oxygen becomes available again.
If oxygen IS available, Pyruvate is converted to Acetyl coenzyme-A and enters the Krebs cycle and electron transport chain (whole other topics). That whole sequence yields a lot of energy (ATP/NADH/FADH) but takes much longer. Hope that helps!