Question

a researcher investigates an organism found on the ocean floor. the organism is asymmetrical. it lacks a body cavity, body tissues, organs, and a nervous system. the researcher finds that the organism can fully regenerate itself if parts of its body are broken off. into which phylum should the researcher classify the organism?
a. mollusca
b. cnidaria
c. porifera
d. arthropoda

Explanation:

• Mollusca (A): Have a body cavity (coelom), complex organ systems. So this option is incorrect.
• Cnidaria (B): Radial symmetry. So this option is incorrect.
• Porifera (C): Asymmetrical, lack true tissues, organs, body cavity. Have high regenerative capacity. This matches the description.
• Arthropoda (D): Bilateral symmetry, complex organ systems. So this option is incorrect.

Answer:

C. Porifera