Protein content declined in the endosperm while an increase was noticed in root and shoot of young seedlings ofS. vulgare andZ. mays. Seedlings of both plants in light had a larger pool of α-alanine, leucine-phenylalanine, glutamic acid, aspartic acid, valine, asparagine, serine-glycine and γ-aminobutyric acid than other amino acids. Tyrosine, proline, threonine and tryptophan which were recorded in light could not be detected in dark. Asparagine and glutamine increased with the seedling growth in most of the samples studied. Phosphoenolpyruvate and pyruvic acid constituted the bulk of keto acid pool while succinate, malate and citrate of organic acid pool. Protein content and citric acid level were found higher in light than in dark grown seedlings of both plants. The higher level of PEP and pyruvic acid in young shoots in light and their sharp decline at advanced stages may be due to a shift from C3 to C4 metabolism.