_ lack respiratory and excretory systems.
graptolites insects ferns barnacles fossil fuels Allergies starfish parasites
A B C D E F G H
Echinoderms are represented by the starfish.
Starfish lack respiratory and excretory systems.
_ lack respiratory and excretory systems. (A) graptolites (B) insects (C) ferns (D) barnacles (E) fossil fuels (F) Allergies (G) starfish (H) parasites