Identify the organism that is NOT a pseudocoelomate.

Correct option is D

The correct answer is (d) Scorpions.

Scorpions are arthropods, and arthropods are coelomates, meaning they possess a true coelom (a body cavity entirely lined with mesoderm). In contrast, pseudocoelomates have a body cavity that is only partially lined with mesoderm.

Pseudocoelomates (like Ascaris, Ancylostoma, and Wuchereria) have a pseudocoelom, which is a body cavity not entirely lined with mesoderm. These organisms belong to the phylum Nematoda.

Information Booster:

• Pseudocoelomates: Organisms with a body cavity not fully lined by mesoderm. Examples include roundworms (phylum Nematoda), such as Ascaris, Ancylostoma, and Wuchereria.
• Coelomates: Organisms with a true coelom, fully lined by mesoderm. Examples include arthropods (like scorpions), annelids, and mollusks.
• Scorpions: Belong to the class Arachnida, which falls under the phylum Arthropoda, known for having a true coelom.