Alike: They are both multicellular, they consist of many cells working together. They are both eukaryotic, they have DNA in the form of chromosomes contained within a distinct nucleus.
Difference: Sponges have multiple cell types that are geared toward executing various metabolic functions. Sponges have multiple cell types that are geared toward executing various metabolic functions.
Cnidarians have outer and inner tissue layers sandwiching a noncellular mesoglea. Cnidarians possess a well-formed digestive system and carry out extracellular digestion.
