Invertebrate
From Simple English Wikipedia, the free encyclopedia
Invertebrate is a kind of animal that does not have a spinal column or backbone. It is the opposite of vertebrate, that means if an animal is not a vertebrate (fish, reptile, amphibian, bird, or mammal), it is an invertebrate. Some examples of invertebrate animals are:
- Arthropods (arachnids, crustaceans, insects, and others);
- Molluscs (octopuses, squids, and others);
- Echinoderms — starfish, sea urchins, sea cucumbers
- Porifera — sponges
- Cnidarians — jellyfish
- Platyhelminthes — flatworms
- Nematoda — roundworms
- Annelida — segmented worms
- Bryozoa — sea mats (occasionally resemble corals)
Insects have no bones, but they have a skeleton on the outside of their bodies that scientists call an exoskeleton. It is like our skin, only it is hard.
Sharks and related skates and rays are vertebrates with cartilage instead of bones.
