to help support and maintenance the skeleton, pigment cells, cells to detect motion on the animal's surface, and sometimes gland cells which secrete sticky fluids or even toxins. the different groups of echinoderms digestive system echinoderms have a simple digestive system with a mouth, stomachs, intestineand...
they are the one that are responsible for sustaining life on this planet. albeit,... continue reading science plastids facts – the cheat-sheet you will need virupakshi august , membrane-bound cell organelles found in plant cells, algae and some of the eukaryotic cells, plastids play a very important...