Developmental patterns of embryos from high and low protein wheat (Triticum aestivum) grain produced under varied fertilizer conditions were compared. High protein grain produced seedlings 25% heavier with 25% more total RNA, 30% more DNA, 40% more amino acids, 60% more ribosomes, and 80% more soluble protein content than that of low protein seed. Consistently higher glutamine synthetase and alpha-amylase and lower acid phosphatase activities were observed in high protein seeds, though the isozyme pattern of alpha-amylase was not different in the two kinds of seeds. The high total ribosomes and particularly, polysome content observed in high protein seeds may be responsible for the rapid growth and high yield of these seeds.