Planarian worms

Planarian worms are freshwater flatworms known for their remarkable ability to regenerate lost body parts. They have a simple, soft body with a head featuring light-sensitive eye spots and a mouth on the underside. Their bodies are made up of specialized cells called neoblasts, which allow them to replace damaged or missing tissue, enabling regeneration of entire worms from small fragments. Planarians are often studied in science because their regenerative capacity provides insights into growth, healing, and stem cell biology. Despite their simplicity, they are complex organisms that demonstrate sophisticated biological processes.