text: Parazoans differ from their choanoflagellate ancestors in that they are not microscopic and have differentiated cells , but unlike `` true animals '' ( Eumetazoa ) , they do not have tissues .
simplified: Parazoans differ from their choanoflagellate ancestors in that they are macroscopic and have differentiated cells , but unlike `` true animals '' ( Eumetazoa ) , they do not have tissues .