Author: komogo3
Text: My science book states that a cut up starfish can regrow into
more starfish. I want more information. Can an arm regenerate a whole new
starfish? I have trouble believing this.
Response #: 1 of 1
Author: Jim Murray
Text: Starfish, also known as sea stars, (they are not fish) are
capable of regenerating even one arm into a whole new body. This is only
possible if the arm includes part of the central disc. If you cut off only
the tip of an arm, that tip will not regenerate, but the animal will grow
another arm. I have seen a single arm nearly 8 inches long with small 1/2
inch arms growing off of it, it will eventually become a whole new sea star.
If you cut a sea star in quarters, right down the center, each piece will grow
into a whole new sea star. I do not know how many pieces one can cut any one
starfish into and still have each regenerate. As long as a piece has part of
the central disk, it should regenerate into a whole organism. But if you cut
a starfish in half, and then let it grow into an whole one before cutting it
in half again, one should be able to do that indefinitely.
NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators.
Argonne National Laboratory, Division of Educational Programs, Harold Myron, Ph.D., Division Director.
