cracks in the same person on the periodic desk of pairs have similar northward
cracking is chemical_process. ixocarpalactone is withanolide. perulactone is withanolide. cracking_reaction is chemical_decomposition. cracking is separating. fault is crack. toe_crack is sand_crack. tetrad is homologous_chromosome_pair. parallel_axiom is euclid's_postulate. perulactone is not withanolide.