Invertebrates are animals that do not have a backbone.
Mollusks-soft bodied animals that have a shell. clams, oysters, squids/octopuses, snails and slugs.
cnidarians--are animals with armlike parts called tentacles with stinging cells.
sponges-simplest kind of invertebrate.
echinoderms- have spiny skin and endoskeleton.
arthopods-have jointed legs and a divided body. (exoskeleton)
There are 4 groups of arthropods: crustaceans, arachnids, insects and centipedes/millipedes.
All insects are arthropods, but not all arthropods are insects!
How can having an exoskeleton be a disadvantage?
Arthropods have to shed their exoskeleton in order to grow bigger. When arthropods shed their exoskeleton, they are left vulnerable until their new exoskeleton grows back. This makes them easy prey for predators.
What is the biggest difference between an echinoderm and a vertebrate? A backbone!
Our skull and skeletal system is an endoskeleton. The biggest difference between an echinoderm that has an endoskeleton and animals that have a skeleton system is our backbone. Echinoderms are invertebrates and they do not have a backbone.
Vertebrates: are animals that have a backbone.
Fish: bony, cartilageous, jawless cold-blooded
mammals:live birth except spiny anteater and platypus, have hair or fur, warm-blooded and feed young milk.
amphibians: live part life in water and other on land, moist skin, and cold-blooded.
reptiles: scales, cold-blooded
birds:warm-blooded, feathers, beaks