Glycolysis is a term that describes a series of reactions that take place within various organisms whereby glucose is broken down and forms two pyruvate molecules, two NADH molecules and two adenosine triphosphate, or ATP. ATP is the principle molecule used for energy by most living organisms. A single ATP molecule contains 7.3 kilocalories of energy whereas a single glucose molecule has the potential to produce energy equivalent to 720 kilocalories. The theoretical efficiency of glycolysis as a means of energy production within the cell can be easily calculated using these values.
Determine the amount of energy produced by glycolysis in kilocalories. This is accomplished by multiplying the number of moles of ATP formed by the amount of energy, in kilocalories per mole, of each ATP molecule. There are 2 moles of ATP produced in glycolysis with each mole containing 7.3 kilocalories per mole, which results in a total of 14.6 kilocalories of energy produced: 7.3 kcal/mol ATP * 2 mol ATP = 14.6 kcal.
Set up a ratio of the amount of energy produced in glycolysis over the total amount of energy in a single glucose molecule: 14.6 kcal / 720 kcal.
Divide the previously determined ratio and convert the result to a percentage to identify the efficiency of glycolysis. There are 14.6 kcal of energy produced in glycolysis from a single glucose molecule containing 720 kcal, thus identifying the efficiency of glycolysis as 2%: 14.6 kcal / 720 kcal = 0.02 or 2%.