They have muscles like us, except theirs are smaller and are connected to the inside of their exoskeletons, instead of wrapping around the endoskeleton like we have.
All insects present an exoskeleton, so all insects are arthropods.
Barnacles are crustaceans( a type of arthropods)
Compound Eyes
polysaccharides
cardiac muscles
They are invertabrates. Some person on this site said that they are arthropods, but he/she is definetly wrong. They are closely related on the phylum tree, but they aren't exactly arthropods. They are invertabrates. Ps. arthropods are a type of invertabrate. :)
which type of muscles cannot be contolled
All insects are arthropods. The phylum Arthropoda contains the classes Insecta (insects), Crustacea (crabs, lobsters, etc), Chelicerata (arachnids) and a few others.
voluntary muscles
Involuntarily controlled muscles
It is not likely that the annelids evolved from the arthropods is as much as they are the much simpler of the two groups of organisms. The arthropods have a well developed open circulatory system, segmented muscles and a complex nervous system (including eyes and chemoreceptors, the antennae) and an exoskeleton.
They express the characteristics inherent to arthropods. All insects are arthropods. Not all arthropods are insects.