The total mass attenuation coefficients (μ t ) (cm(2)/g) and atomic, molecular, and electronic effective cross sections have been calculated for nonessential amino acids that contain H, C, N, and O such as tyrosine, aspartate, glutamine, alanine, asparagine, aspartic acid, cysteine, and glycine in the wide energy region 0.015-15 MeV. The variations with energy of total mass attenuation coefficients and atomic, molecular, and electronic cross sections are shown for all photon interactions.