Phylum Porifera - Biology 2e

Anatomy and Physiology Porifera possess no head and no tail; they are basal metazoans characterized by the absence of true tissues , a

Class Demospongiae is the largest in the phylum Porifera and encompasses nearly 8,000 accepted species in three subclasses: Keratosa,

porifera Porifera contain the sponges: the most ancient of all animal groups They originated in the Cambrian period around 600 million years ago

porifera Sponges the members of the phylum Porifera are a basal animal clade as a sister of the diploblasts They are multicellular organisms that have bodies full