The radula is an anatomical structure for feeding (sometimes also compared to a tongue), It is a characteristic feature of the mollusks and is found in every class of mollusk except the bivalves. Eg. Pila
Malpighian tubules or MTs are very highly specific organs of arthropods for excretion and osmoregulation. Eg. Bombyx
Comb-plate is a locomotory organ made up of a row of very strong cilia fused together. Eg. Pleurobrachia
Flame cells are specialized for excretion present in some freshwater invertebrates like flatworms, rotifers, and nemerteans. Eg. Taenia