Invertebrates
7 questions tagged Invertebrates — spanning every one of the seven Ws.
Why do shrimps and crustaceans have hard shells?
Their shells are exoskeletons that protect the body and provide support. Because the shell does not grow with the animal, they must molt to get bigger.
What is a nudibranch?
A nudibranch is a type of shell-less sea slug known for bright colors and unusual body forms. Many species are predators or specialize in eating sponges, hydroids, or other small animals.
Which creature has the most legs?
Among known animals, certain millipedes have the most legs. The record-holder, Eumillipes persephone, has more than 1,300 legs.
What is a sea cucumber?
A sea cucumber is a marine animal related to starfish and sea urchins. It feeds on organic material in sediment and helps recycle nutrients on the seafloor.
What is a sea star?
A sea star is a marine animal with a star-shaped body and usually five arms. It can extend its stomach outside its body to feed.
What is a sea urchin?
A sea urchin is a spiny marine animal related to sea stars and sea cucumbers. It grazes on algae and uses tube feet and spines to move and protect itself.
How do jellyfish sting people and fish?
Their tentacles carry microscopic stinging cells that fire toxin-filled barbs when triggered.