Give the steps of breakdown of glucose in an organism
Answers
During glycolysis, glucose is broken down in ten steps to two molecules of pyruvate, which then enters the mitochondria where it is oxidised through the tricarboxylic acid cycle to carbon dioxide and water. Glycolysis can be split into two phases, both of which occur in the cytosol. Phase I involves splitting glucose into two molecules of glyceraldehyde-3-phosphate (G3P) at the expense of 2 ATP molecules, but allows the subsequent energy-producing reactions to be doubled up with a higher net gain of ATP. Phase II converts G3P into pyruvate, with the concomitant generation of 4 ATP molecules, giving a net gain of 2 ATP per glucose molecule. Glycolysis, therefore, provides the cell with a small amount of energy, and, in aerobic cells, provides the starting materials for the complete oxidation of glucose to carbon dioxide and water.
