Classification and Variation

Classification and variation.
There are 5 kingdoms of living things:- Animal kingdom Plant kingdom, Fungi kingdom Monera kingdom and Protactista.
Animal kingdom is divided into groups: vertebrates, Echinoderms, Jelly fish, Flatworm, Annelids, Nematodes, Arthropods and Molluscus.
Annelids have long, thin, soft bodied divided into segments or rings.
Nematodes have thin, cylindrical bodies that are not divided into segments.
Arthropods are divided into 4 groups:
Myriapods : have 1 pair of antenna Long cylindrical or flat bodies with many legs.
Crustaceans: have 2 pairs of antennas.
Insects :have 1 pair of antenna 3 pair of legs Up to 2 pair of wings
Arachnids: have no antennae or wings but 4 pairs of leg.
Mollis (Molluscus) in Latin means soft.
Molluscus have soft bodies and some animals have shell to protect their bodies
For example Snail: it has a coiled shell from which it pushes its head and fleshy foot when it wants to move or feed.
Slug has a saddle like structure called mantle which does not provide any protection.
Five groups of vertebrates:
Bony fish: Scales, fins, eggs laid in water
Amphibians: smooth skin, eggs laid in water
Reptiles: scales, soft-shelled, eggs laid on