Answer – The products of glycolysis are two molecules of ATP, two molecules of NADH and two pyruvate molecules.

Explanation:

Glycolysis is the process through which cells extract energy from a glucose molecule. It is the first stage of cellular respiration, but does not require oxygen. Given the latter feature, it takes place in all organisms, even those that are anaerobic. 

Glycolysis is a ten-step process, with two phases. The first phase requires energy, while the second releases it.

The steps in the energy-requiring phase are as follows:

1. In the presence of a catalyst, hexokinase, the glucose molecule is phosphorylated. A  phosphate molecule from an ATP molecule is attached to the glucose molecule, producing a more reactive version of it – glucose-6-phosphate. This also prevents the glucose from leaving the cell as the negative charge of the phosphate repels it from the interior of the membrane’s bilayer.
2. In the presence of a second catalyst, an isomerase, the glucose-6-phosphate is converted into its isomer – fructose-6-phosphate.
3. The fructose-6-phosphate molecule undergoes another phosphorylation, with a second ATP molecule donating its phosphate group in the presence of an enzyme called phosphofructokinase. The result is a molecule of fructose-1,6-bisphosphate.
4. The fructose-1,6-bisphosphate is split into two in the presence of the enzyme aldolase. There are now two three-carbon sugars that are isomers of one another – dihydroxyacetone phosphate (DHAP), and glyceraldehyde-3-phosphate. 
5. An isomerase converts the DHAP into another molecule of glyceraldehyde-3-phosphate.

The first phase of glycolysis utilizes two molecules of ATP, an energy source. The six-carbon molecule of glucose that the process started with is broken down into two three-carbon sugar molecules of glyceraldehyde-3-phosphate which undergo further transformation in the second phase.

The steps of the energy-releasing phase are as follows:

1. Electrons are released by the glyceraldehyde-3-phosphate when it is oxidized. They are attracted to a coenzyme called NAD⁺ which becomes NADH. This reaction produces energy, resulting in the sugar phosphorylating to produce 1,3-biphosphoglycerate.
2. A catalyst called phosphoglycerate kinase facilitates a reverse reaction where the 1,3-biphosphoglycerate donates its phosphate group to an ADP molecule, making it ATP. By giving up the phosphate, the sugar is now 3-phosphoglycerate.
3. An isomerase helps the phosphate group in the sugar move to its second carbon, resulting in 2-phosphoglycerate.
4. The 2-phosphoglycerate molecule undergoes a dehydration reaction and loses a water molecule to produce phosphoenolpyruvate (PEP) which is reactive.
5. The PEP donates its phosphate group to another ADP molecule (converting it into ATP), and becomes pyruvate. 

The products of a single glyceraldehyde-3-phosphate molecule going through the second phase of glycolysis are 2 ATP molecules, and one each of NADH and pyruvate. As there are two molecules of the three-carbon sugar at the beginning of this phase, both of which go through it individually, the overall yield is 4 ATP molecules, and two each of NADH and pyruvate. However, since the first phase of glycolysis itself uses up two ATP molecules, at the end of the process as a whole, we have two new ATP molecules.

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