GENERAL HISTOLOGY

Detailed explanation-1: -Using tiny, suction-cupped tube feet, they pry open clams or oysters, and their sack-like cardiac stomach emerges from their mouth and oozes inside the shell. The stomach then envelops the prey to digest it, and finally withdraws back into the body.

Detailed explanation-2: -It is these suction-bottomed tubes that the sea star uses to move about. It draws in water and channels it to canals that run throughout its body, usually ending in the tube feet. By changing the pressure of water in its body, the sea star can move the tubed feet, and thus move forward.

Detailed explanation-3: -Sea stars, commonly called, “starfish, ” are not fish. Sea stars live only in saltwater. Sea water, instead of blood, is actually used to pump nutrients through their bodies via a ‘water vascular system. ‘ Also, sea stars move by using tiny tube feet located on the underside of their bodies.

Detailed explanation-4: -In ophiuroids the tube feet are used to gain a hold on a surface and to pass food to the mouth.

Detailed explanation-5: -Each tube foot is connected to its own tiny sac called an ampulla, that sits inside the body of the starfish. When the starfish squeezes the ampulla it extends the tube foot in the direction it wants to go.