animals without backbones are invertebrates.
octopi and squids have no shells, but are invertebrates because they contain no backbone.
if they had a backbone, they'd be vertebrates.
Arthropods are defined to be invertebrates that have an exoskeleton ( an external skeleton).
Many invertebrates have shells or exoskeletons which can be used to anchor muscles.
bugs with shells bugs with shells
shells are important to some invertebrates groups because for some of them, that's their home
Decapods (Lobsters, crabs etc.) are examples of invertebrates that have shells or chitinous bodies that protect their bodies.
I think you´re looking for molluscs - snails and the like.
Barnacles are invertebrates because their shells are outside of their body - they do not have an internal skeleton with a backbone.
limestone. A rock made up mainly of the shells or fragments of shells of megascopic (clams, oysters, snails) animals is a coquina. If the rock is composed of the shells (tests) of microscopic plants and animals it may be called chalk. Limestone can be a hardened chemical precipitate of CaCO3 without an organic source, and take many forms: oolite for example.
Mollusks are all invertebrates because they have no internal skeleton with a backbone. Their shells are outside of their body.
Yes because they do not have a backbone, they have shells, instead.
insect
MOLLUSK