Question

How many ATP are used and made in Glycolysis, Krebs cycle, and electron transport chain?

Answer 1

Hint: The ATP is the energy currency of the cell. It is an important molecule for the storing and transferring of energy in our body. This is either consumed or generated in various biochemical reactions in our body.

Complete answer:
Glucose is the carbohydrate that is the most readily available source of energy in our body. It gets breakdown in our cells to provide energy to our cells in the form of ATP. The complete process of formation, breakdown, and inter-conversion of glucose into various molecules is carbohydrate metabolism. Glycolysis, Krebs cycle, and electron transport chain are the main process in carbohydrate metabolism. In all the cycles the ATP or other form of energy is produced or used.

Glycolysis: In glycolysis, the glucose (6 carbon molecules) gets broken into 2 molecules of pyruvate (3 carbon molecules). This requires 2 ATP molecules and produces 4 ATP and 2 NADH molecules. So the net reaction produces 2ATP.

Krebs cycle: Here for a pyruvate molecule 1 ATP, 1 FADH2, and 5 NADH molecules are produced so for a glucose molecule it becomes twice i.e. 2 ATP, 2 $FADH_2$ , and 10 NADH are produced.

Electron transport chain: Here all the other currencies of energy like NADH and FADH are converted to ATP. After complete oxidation of one molecule of glucose total ATP yield is equal to 32. This is calculated as 2.5 ATP per NADH, 1.5 ATP per $FADH_2$ (10* 2.5 NADH +2*1.5 $FADH_2$ + 4 ATP = 32).

Note: The glycolysis takes place in the cytosol, Krebs cycle in matrix on mitochondria and electron transport chain in the inner mitochondrial membrane.