DEFINITIONS AND KEY POINTS FOR OBJECTIVES OF THE ECHINODERMS
TERMS
DEFINITIONS
Filter feeder
The animals ‘‘ Inch filter food particles form the \\ ater current are called filter feeders.
Ossieles
Ossicle are endodcrmal skeleton of echinoderms.
Water vascular system
Water vascular system composed of water-tilled canals. These canals arc used in locomotion. attachment and feeding.
Enterocuelous
This coelomis formed by the out pocketing of the embroynic gut.
Tube feet
Tube feet arc extensions of the canal system.
Coelomocytcs
Coelomocyctes are cells that engulf and transport waste particles within the body.
Dermal branchiae
Thin folds of body wall extend between ossicles. It is called dermal branehiae. It is involved in gas exchange.
Pedieellarieae
The aboral surface of sonic sea stars has numerous pincher like structures called pedicellarieae.
Spanning pheromones.
This pheromone induced the other sea stars to spawn
.Autotomy
If a brittle star is grasped by an arm, the contraction of certain muscles separate the arm form the body. This process is called autotomy.
Aristotle’s lantern
.This apparatus can be projected from the mouth. Aristotle’s lantern consists of 35 ossicles and attached muscles. It cuts food into small pieces for ingestion.
Evisceration
Sometimes. contraction of the body expels the one or both respirators tree, the digestive tract, and the gonads through the anus. This process is called evisceration.
