Cnidarians are best described as which tissue category?

Cnidarians are best described as which tissue category?

• A. Diploblastic
• B. Triploblastic
• C. No Tissues
• D. Pseudotissue

Answer: (A)

Cnidarians have tissues that arise from two embryonic germ layers: the outer ectoderm and the inner endoderm (gastrodermis), separated by a jelly-like mesoglea. This two-layer organization defines them as diploblastic. They lack a mesoderm, so they aren’t triploblastic, which would involve three germ layers. While they do possess true tissues, they don’t form organs from three germ layers, which is why diploblastic best fits their level of organization. Sponges, on the other hand, have no true tissues at all, so that option wouldn’t apply.

Cnidarians have tissues that arise from two embryonic germ layers: the outer ectoderm and the inner endoderm (gastrodermis), separated by a jelly-like mesoglea. This two-layer organization defines them as diploblastic. They lack a mesoderm, so they aren’t triploblastic, which would involve three germ layers. While they do possess true tissues, they don’t form organs from three germ layers, which is why diploblastic best fits their level of organization. Sponges, on the other hand, have no true tissues at all, so that option wouldn’t apply.