An Overview of Metabolism and Biochemical Energy Catabolic stages: Stage 1 Food is digested by hydrolysis of ester,glycoside (acetal), and peptide (amide)bonds to yield primarily fatty acids plus glycerol,simple sugars,and amino acids Stage 2 Molecules are further degraded in the cytoplasm of the cells to yield acetyl groups attached by a thioester bond to the large carrier molecule coenzyme A The resultant compound,acetyl coenzyme A (acetyl CoA),is a key substance in the metabolism of food molecules and in numerous other biological pathwaysCatabolic stages: Stage 1 ▪ Food is digested by hydrolysis of ester, glycoside (acetal), and peptide (amide) bonds to yield primarily fatty acids plus glycerol, simple sugars, and amino acids Stage 2 ▪ Molecules are further degraded in the cytoplasm of the cells to yield acetyl groups attached by a thioester bond to the large carrier molecule coenzyme A ▪ The resultant compound, acetyl coenzyme A (acetyl CoA), is a key substance in the metabolism of food molecules and in numerous other biological pathways An Overview of Metabolism and Biochemical Energy