Which phylum consists of sponges with no true tissues?

• A. Polychaeta
• B. Polyp
• C. Porifera
• D. Radial Symmetry

Answer: (C)

Sponges are grouped in the phylum Porifera and are characterized by cellular-level organization rather than true tissues. Their bodies are built from loosely arranged cells (such as choanocytes and amoebocytes) embedded in a gelatinous matrix, with no germ layers or tissue layers to form organs. This simple organization is what distinguishes Porifera from other animal groups, making them the correct choice for a phylum that consists of sponges with no true tissues.

The other options describe different ideas: Polychaeta are segmented worms with true tissues and organ systems; Polyp refers to a body form found in cnidarians (which do have tissues); Radial symmetry is a type of body symmetry, not a phylum.