AP BIOLOGY

Detailed explanation-1: -First ATP is produced when glyceraldehyde-3-phosphate ⇢ 1, 3 diphosphoglycerate. Secondly ATP is produced when phosphoenolpyruvate ⇢ pyruvate. These reactions occur twice for both molecules of 3-phosphate. Thus, a total of 4 ATPs are produced during glycolysis.

Detailed explanation-2: -Results of Glycolysis The energy to split glucose is provided by two molecules of ATP. As glycolysis proceeds, energy is released, and the energy is used to make four molecules of ATP.

Detailed explanation-3: -One glucose molecule yields four ATP molecules in total during glycolysis. Since 2 ATP molecules are used up in the first phase of glycolysis, there is a net gain of 2 ATP molecules. In addition, glycolysis results in the production of 2 NADH molecules.

Detailed explanation-4: -During glycolysis, glucose ultimately breaks down into pyruvate and energy; a total of 2 ATP is derived in the process (Glucose + 2 NAD+ + 2 ADP + 2 Pi–> 2 Pyruvate + 2 NADH + 2 H+ + 2 ATP + 2 H2O). The hydroxyl groups allow for phosphorylation.

Detailed explanation-5: -Glycolysis produces two pyruvate molecules, four ATPs (a net of two ATP), two NADH, and two H2O. Therefore, without the presence of oxygen, glycolysis is the only process that can occur, and only two ATP molecules may be produced for each glucose molecule.