Glycolysis and Oxidative Phosphorylation

Glycolysis

Oxidative Phosphorylation

Glycolysis

Glycolysis occurs in the cytoplasm in the absence of O₂and involves the following:

1. Two molecules of ATP are use to phosphorylate glucose and start glycolysis

2. The phosphorylated molecule is then broken down in a series of reactions into two three carbon molecules (lysis).
3. Two molecules of NAD⁺ capture and are reduced to 2 molecules of
NADH + H⁺
3. Four molecules of ATP are produced by substrate phosphorylation
4. The end product pyruvate may then either undergo areobic respiration in the mitochondria or anaerobic respiration (fermentation).

Summary of Products of Glycolysis (Net Gain of 2 ATP)

Oxidative Phosphorylation

Most of the ATP of Cell is produced in the Mitochondria. This a complex and multi-step process. The following is an attempt to step through this process.

Coenzymes NAD⁺ and FAD act as carriers of electrons and protons in the form of Hydrogen atoms to the Electron Transport Chain (ETC).

The following is a diagram of first the reduction of NAD⁺when it captures atoms from the oxidation of glucose and then the oxidation of NADH + H⁺ when it releases atom to the ETC. Notice how the is then recycled to pick up more.

The protons and electrons from the Hydrogen atoms are then used to power the proton pump of the electron transport chain.

atoms release protons and electrons