One molecule of glucose produces two molecules of pyruvate. During this reaction, two ATP are used (steps 1 and 3) and four ATP are generated (two in step 6 and two in step 9), yielding a net production of 2 ATP per glucose. Also, one NADH is produced per glyceraldehyde-3-phosphate to yield a total of 2 NADH per glucose. 

Glucose is a six-carbon molecule, and pyruvate is a three carbon molecule. From the name, we know that glycolysis involves the lysis, or splitting of glucose. As such, the products of glycolysis include two molecules of pyruvate.

Each glucose molecule is converted into two pyruvate molecules, with three carbon atoms each. During glycolysis, two NADH molecules are formed per glucose. Oxygen is not necessary -- one major feature of glycolysis is that it produces energy anaerobically. It yields ATP, with a net gain of two ATP molecules for each glucose consumed.

Two separate steps of glycolysis each create 2 ATP (4 ATP total). However, the first and third steps involved in this process require an input of energy in order to work. Thus, the net yield of ATP from glycolysis is actually only 2 ATP. These ATP are produced via substrate-level phosphorylation.

Glycolysis has a net yield of 2 ATP per glucose molecules. The Krebs cycle produces 2 GTP molecules per glucose. The electron transport chain and ATP synthase are the main producers of ATP in cellular respiration. The pyruvate dehydrogenase complex, however, does not yield any ATP (or any other nucleoside phosphates). It simply produces acetyl-CoA from pyruvate, releasing one molecule of carbon dioxide per pyruvate.

In the liver, glucokinase irreversibly converts glucose in the cell to glucose-6-phosphate. Phosphofructose kinase-1 irreversibly converts fructose-6-phosphate to fructose-1,6-bisphosphate. Pyruvate kinase converts phosphoenolpyruvate to pyruvate. All the other enzymes listed catalyze reversible glycolysis reactions.

Gluconeogenesis does not convert glucose into pyruvate, rather it builds glucose from non-carbohydrate organic compounds. All of the other answer choices are possible fates of glucose once it enters the cell.

Glycolysis is a process that takes place via ten reactions, involving the activity of multiple enzymes and occurs in the cytoplasm of the cell in two distinct phases: an energy consumption phase and an energy production phase. The first step in glycolysis is the conversion of glucose to glucose-6-phosphate through the consumption on one ATP molecule. Glucose is reacted upon by the enzyme hexokinase to carry out this step. Kinases are a group of enzymes that add phosphate groups by removing them from an ATP. In the second step, glucose-6-phosphate is then reacted upon by phosphoglucose isomerase. Isomerases are a group of enzymes that rearranged the structure of a molecule without changing the molecular formula. In this case the phosphoglucose isomerase rearranges the glucose-6-phosphate into fructose-6-phosphate. The third step involves another kinase: phosphofructokinase-1. This enzyme attached another phosphate group to fructose-6-phosphate, creating fructose-1,6-bisphosphate. In the fourth step, this molecule is then reacted upon by fructose bisphosphate aldolase. An aldolase is an enzyme that creates or breaks carbon-carbon bonds. This step results in the creation of two molecules: dihydroxyacetone phosphate and glyceraldehyde-3-phosphate. The fifth step involves another isomerase, triose phosphate isomerase, which converts the dihydroxyacetone into glyceraldehyde-3-phosphate (G3P).The sixth step involves the enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH). GAPDH moves a hydrogen onto the electron acceptor . A phosphate group from inorganic phosphate instead of ATP replaces the hydride group that was taken from G3P. This creates the molecule 1,3 bisphosphoglycerate. The seventh reaction involves yet another kinase, phosphoglycerate kinase. Kinases can also take phosphate groups away. During this step, two phosphate groups are transferred from the 1,3 Bisphosphoglycerate molecules onto 2 molecules of ADP to create two molecule of ATP. The 1,3 Bisphosphoglycerate then becomes 3-phosphoglycerate. The eighth reaction involves the enzyme phosphoglycerate mutase which is essentially another isomerase. It converts 3-phosphoglycerate to 2-phosphoglycerate. The ninth reaction involves the enzyme enolase which produces a double bond by removing the hydroxyl group on 2-phosphoglycerate which results in phosphoenolpyruvate (PEP). The tenth and final reaction of glycolysis involves the enzyme pyruvate kinase. Just like the previous kinase reaction, this kinase is going to remove phosphate groups from the molecule to produce 2 molecules of ATP (one per molecule of PEP created from 1 molecule of glucose. The final product of glycolysis is pyruvate.

Phosphofructokinase catalyzes the most regulated step of glycolysis and limits the reaction rate of glycolysis. Glucose is converted to pyruvate during glycolysis, not lactate, which is the case in some organisms (humans) through the process of fermentation. Glucokinase, not hexokinase is found in the liver, fructose-2,6-bisphosphate activates, not inhibits phosphofructokinase.

An epimerase inverts the stereochemistry at a particular carbon, but it cannot add additional carbons. While hexokinase can phosphorylate fructose into a glycolytic intermediate in most tissue, the liver does not contain any hexokinase. In the liver, fructose is phosphorylated by fructokinase into fructose-1-phosphate. This is cleaved by an aldolase to form dihydroxyacetone phosphate (DHAP), a glycolytic intermediate, and glyceraldehyde, a precursor to glyceraldehyde-3-phosphate (G3P), another glycolytic intermediate. Glyceraldehyde can either be phosphorylated into G3P or be used to promote fat storage.