yes
Cephalopods
Members of the class Aplacophora are mollusks that have an internal plate instead of a shell. Aplacophorans lack a protective shell but possess calcareous spicules or scales in their skin. These marine mollusks are often found in deep sea environments.
Cephalopods such as octopuses, squid, and cuttlefish do not have shells. They have evolved with a reduced internal or external shell, or in some cases, no shell at all. This allows for greater agility and flexibility in movement.
Cephalopods
Due to the evolutionary advantage of having a 'curly' shell instead of a straight long shell ( Like in early forms of cephalopods) the 'curly' shell much easier to transport, is stronger, and allows snails to move into small crevasses.
Slugs are gastropods. All slugs are shell-less.
The gladius squid is distinguished from other cephalopods by its long, slender body and distinctive gladius, or internal shell. This shell helps the squid maintain its shape and provides protection. Additionally, the gladius squid is known for its ability to swim quickly and efficiently, making it a formidable predator in the ocean.
Cephalopoda
Most of Mollusks protect themselves with help of shell . Shell is hard protective covering made up of CaCO3. Cephalopods are not protected by shell .
because the shell acts as a barrier
because of its hard shell
Yes, an octopus is an cephalopod which means head foot. Other cephalopods include cuttlefish, squid, and an nautilus which is the only cephalopod that still carries a shell.