AP BIOLOGY

Detailed explanation-1: -Organisms of the phylum Echinodermata show some of the most impressive regenerative feats within the animal kingdom. Following injury or self-induced autotomy, species in this phylum can regenerate most tissues and organs, being the regeneration of the muscular systems one of the best studied.

Detailed explanation-2: -The ability to regenerate, or regrow, lost or destroyed parts is well developed in echinoderms, especially sea lilies, starfishes, and brittle stars, all of which can regenerate new arms if existing ones are broken off.

Detailed explanation-3: -Examples of echinoderms include sea stars, sea urchins, sea cucumbers, brittle stars, and feather stars (Fig. 3.83).

Detailed explanation-4: -These animals are known to undergo regeneration of various organs, including respiratory trees, longitudinal muscles, radial nerve cord, tentacles, polian vesicles, and digestive tract, among others.

Detailed explanation-5: -As adults, echinoderms can regenerate many organs, including limbs, disc, gut, spines and podia and, in some species, regeneration is used for asexual reproduction2, 3.