Elementary plant Biochemistry and Biotechnology (2+1)

Metabolic processes in carbohydrates

Carbohydrate Metabolism

i. Glycolysis

• Glycolysis is the sequence of reactions that convert glucose into pyruvate with the concomitant trapping of the energy as ATP.

ii. The citric acid cycle

• It is the final common oxidative pathway for carbohydrates, fats and proteins. It is also a source of precursors for biosynthesis of various biomolecules.
• The acetyl CoA that enters in this pathway is completely oxidised to carbon dioxide and water with concomitant production of reducing equivalents, namely NADH and FADH2.

iii. The hexose monophosphate shunt

• It is an alternative pathway to the glycolytic pathway and the citric acid cycle for the oxidation of glucose to carbon dioxide and water with the generation of reduced nicotinamide adenine dinucleotide phosphate (NADPH) molecules and ribose 5-phosphate.

iv. Gluconeogenesis

• It is a biosynthetic pathway that generates glucose from non-carbohydrate precursors.

v. Glycogenesis:

• It is a pathway by which glycogen is synthesised from glucose.

vi. Glycogenolysis