Question

what are flame cells

Answer 1

these cells work as excretory cells in few organisms like cockroaches , etc.
they are also cells function like a kidney and remove waste material.
Flatworms have flame cells. Bundles of flame cells are called protonephridia.

hope it helps..

Answer 2

A flame cell is a specialized excretory cell found in the simplest fresh water invertebrates including flat worms.
Flame cells function like a kidney removing waste materials