Invertebrates
Information about Insects and other Invertebrates:
All insect are invertebrates – which means unlike other animals such as mammals, birds, reptiles and amphibians – they do not have a backbone or notochord. 95-98% of all animal species on the planet are classified as such. Therefore, these animals usually have an exoskeleton or shell – but many species don’t even have this. Along with not having a backbone, invertebrates share three other common traits: They are multi-cellular. All the cells have different responsibilities in keeping the animal alive. Also, they have no cell walls, like all other animals. Finally, they reproduce by two reproductive cells coming together to produce a new organism of their species.
The most common invertebrates include the protozoa, annelids, echinoderms, mollusks and arthropods. Arthropods include insects, crustaceans and arachnids. Most invertebrates can move – either crawling, flying, floating or swimming.