AP BIOLOGY

Detailed explanation-1: -In the first step, glucose ⇢ glucose-6-phosphate, ATP is used and gets converted into ADP . Similarly, in the third step, fructose-6-phosphate ⇢ fructose-1, 6-biphosphate, ATP is used. Thus, two ATPs are used in the first three steps of glycolysis. Hence, to split the glucose 2 molecules of ATPs are used.

Detailed explanation-2: -Glycolysis produces 4 ATP molecules. However, 2 ATP molecules are required to initiate glycolysis.

Detailed explanation-3: -Glycolysis: The Foundation of Cellular Respiration This process requires the investment of 2 ATP molecules and yields 4 ATP in addition to the pyruvate and another type of molecule called NADH, which will contribute to the final step of cellular respiration.

Detailed explanation-4: -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.