Section 5.3 – Catabolic Pathways for Carbohydrates, Lipids, and Proteins are Interconnected

Summarize the relationships between the major metabolic pathways of the cell, involving the four biological macromolecules and their components/monomers.

Cells' catabolic and anabolic pathways are highly interconnected. Carbohydrates, lipids, and proteins can each enter shared energy-producing routes such as glycolysis, pyruvate oxidation, and the citric acid cycle. Monosaccharides are converted to glucose or glycolytic intermediates, fatty acids undergo β-oxidation to yield acetyl CoA, and amino acids are deaminated and fed into glycolysis or the citric acid cycle. These interconnections allow flexible energy use and synthesis depending on cellular needs.;

catabolic interconversions

Processes in which complex molecules (like carbohydrates, fats, and proteins) are broken down into smaller molecules, feeding intermediates into central energy pathways such as glycolysis and the citric acid cycle.;

anabolic interconversions

Processes that use intermediates from catabolic pathways as building blocks to synthesize larger biological molecules such as carbohydrates, lipids, and proteins, requiring energy input (ATP and reducing power).;