Glycolysis
- Glycolysis is the first stage of respiration
- It takes place in the cytoplasm of the cell and involves:
- Trapping glucose in the cell by phosphorylating the molecule
- Splitting the glucose molecule into two
- When 1 glucose molecule enters glycolysis, it results in the production of
- 2 Pyruvate (3-carbon-atom) molecules
- Net gain 2 ATP molecules - synthesized from ADP + Pi
- 2 NADH molecules - synthesized from H+ and NAD+
Glycolysis Process Diagram
The process of glycolysis
Exam Tip
It may seem strange that ATP is used and also produced during glycolysis. At the start ATP is used to make glucose more reactive (it is usually very stable) and to lower the activation energy of the reaction. Since 2 ATP are used and 4 are produced during the process, there is a net gain of 2 ATP per glucose molecule.
Memorization of the steps of glycolysis is not required
