Echinoderms lack respiratory and excretory systems.
Starfish and sea urchins are also echinoderms.
Starfish lack respiratory and excretory systems.
what lack respiratory and excretory systems?
Options:
(1) fish
(2) graptolites
(3) starfish
(4) waste
(5) humans
(6) barnacles
(7) insects
(8) ferns