Rotifera tissue organization is described as which of the following?

• A. Triploblasts, eumetazoa
• B. Diploblasts, eumetazoa
• C. Triploblasts, parazoa
• D. Diploblasts, parazoa

Answer: (A)

Rotifers are triploblastic, meaning they develop from three germ layers: ectoderm, mesoderm, and endoderm. This three-layer tissue organization provides true tissues and organs, which places them in the eumetazoans. Diploblastic animals have only two germ layers (ectoderm and endoderm), and parazoans lack true tissues altogether, so rotifers don’t fit those options. The presence of a mesoderm gives rise to muscles and many organ systems, reinforcing their classification as triploblastic eumetazoans.