Produced by Vibrio cholerae, cholera toxin (CT) is a multimeric enterotoxin that transfers ADP-ribose to a G protein, locking adenylate cyclase in an 'on' position.
Starfish, sand dollars, and sea urchins all belong to a group (phylum) of invertebrates known as echinoderms. The word echinoderm means spiny skin, which describes most of the organisms in this phylum.tarfish, sand dollars, and sea urchins all belong to a group (phylum) of invertebrates known as echinoderms. The word echinoderm means spiny skin, which describes most of the organisms in this phylum.
As larvae, echinoderms are bilaterally symmetrical. As they mature, they become radially symmetrical. Most adult echinoderms live on the bottom of the ocean floor. Many echinoderms have suckers on the ends of their feet that are used to capture and hold prey, and to hold onto rocks in a swift current.