Final answer:
Archaeocytes, derived from stem-cell-like archaeocytes, are unspecialized cells found in sponges. They differentiate into multiple cell types and have specialized functions in nutrient transport and spicule formation.
Step-by-step explanation:
Archaeocytes, derived from stem-cell-like archaeocytes, are a type of unspecialized cell found in sponges. Unlike normal stem cells, archaeocytes have the ability to differentiate into multiple cell types and are involved in processes such as nutrient transport and spicule formation. They give rise to specialized cells like collenocytes, lophocytes, sclerocytes, and spongocytes, which have specific functions in supporting the sponge's structure and reproductive processes.