Sea Cucumbers

 When you think of a Sea Cucumber, what do you think of?  Do you think of a cucumber that grows at the bottom of the ocean?  They are actually animals!!  They are an echinoderm with radial symmetry without arms that live in the ocean.  They live with one side permanently on the ground.  They also have a water vascular system (WVS) with tube feet on three areas on the ventral side or underside.  Some species have burrowed under the ground and lost their tube feet.  Small bonelike plates cover their leathery body.  Some eat bottom material and others have tentacles to capture particles or plankton and transfer them to the mouth.  Most have branching tubes called respiratory trees attached to the intestine near the anus.  Some species have branches called the tubules of Cuvier that are attached to or near the bases of the respiratory trees and are ejected when the organism is attacked.  They swell and become sticky as they entangle the predator.  Many sea cucumbers eject their internal organs when they get irritated and later regenerate a new set. 

Sea cucumbers have a single branched gonad.  The eggs are expelled into the ocean and after they’re fertilized they turn into larvae that is free swimming.  Then, after awhile they go through metamorphosis. 

Sea cucumbers are in all seas and at all depths.  Hopefully you’ll see one there instead of your salad.