they represented cell walls ( cw ) , culture filtrates ( cf ) , artificially disintegrated cell material ( xp ) , protoplasms ( pp ) , crude ribosomes ( cr ) , ribosomal 50s subunits ( 50s ) , ribosomal 30s subunits ( 30s ) , ribosomal 16s core particles ( 16s ) and ribosomal-free fractions ( ucs ) .
C0007634
cell
C0035553
ribosomal