Interasting facts about echinoderms

Answer 1

Some Echidnoderms, like starfish and brittlestars, can actually bring their stomach out of their mouth and digest the food outside their body before bringing it back in! This is also the same opening that waste comes out of, FYI. If a starfish happens to lose an arm, it can grow an new one. The center of the starfish is called the disk, and the disk does not have different sections for different organs. Instead, they are all part of the same round, radial pattern, which means that if part of the disk is removed with an arm, a starfish can grow it's body back too! Echidnoderms are very simple, but at the same time, very weird. There are other Echidnoderms besides starfish and brittlestars, including basket stars, serpent stars, sea urchins, heart uurchins, sanddollars, sea cucumbers, feather stars, and sea lilies. Some of these can be very interesting. For example, a sea cucumber has long, stinging tentacles all over it's body. Like the sea stars arms, they easily grow back. For extra defense, it also lets out nasty mucus from its anus that covers the whole sea cucumber, and a predator now can't see it. So they can be extremely fascinating. You just have to look deeper than your Biology textbook!