KINGDOM ANIMALS Invertebrates

KINGDOM ANIMALIA All multicellular, eukaryotic, heterotrophic Invertebrates: – Animals WITHOUT a backbone – Most abundant group – Can reproduce sexually and asexually – 2 most important Phylums Annelida Arthropods

Phylum Annelidas Annelida: segmented worms – Example is the “earthworm” Each worm is segmented: – Septa: a thin sheet of tissue that separates each segment in a worm These animals use their skin for gas exchange and the removal of some wastes – Their skin is extremely permeable Others use “gills” for gas exchange if they live in water

Phylum Annelida Annelid worms have a CLOSED circulatory system – Means blood is contained within a network of blood vessels Movement of annelids: – Use a series of cyclic muscular contractions – Alternate between contraction/relaxation – “wave-like” fashion

Phylum Annelida Reproduction – Most reproduce asexually because they have both male and female sex organs – A few reproduce sexually (polycheate) by the process of EXTERNAL FERTILIZATION 3 classes of annelida – Oligochaetes (earthworms) – Leeches (parasites) – Polychaetes (annelids that live in the ocean) Sandworms, bloodworms

Phylum Arthropods Arthropods: (insects) – Segmented body – Hard exoskeleton – Jointed appendages 3 types of arthropods – Crustaceans – Arachnids – insects

Phylum Arthropods Class Crustaceans – Crayfish, lobster, shrimp, crab – Most live in saltwater – Reproduce sexually Class Arachnida – Spiders, ticks, mites, scorpions – Reproduce sexually and lay eggs

Phylum Arthropods Class Insecta – Have a head, thorax, and abdomen – Have jointed appendages Legs, wings that extend from the body – Have “antennae” and two eyes on their head – Reproduce sexually (2 different life cycles) Incomplete Metamorphosis Complete Metamorphosis – most abundant arthropod!!!

Phylum Arthropods Class Insecta Reproduction – Complete Metamorphosis includes 4 different stages – EGG – LARVA (does not resemble adult) – PUPA – ADULT STAGE Butterflies are an example

Phylum Arthropods Class Insecta Reproduction – Incomplete Metamorphosis includes 3 different stages – EGG – NYMPH (does look like the adult but cannot fly nor reproduce) – ADULT STAGES Grasshoppers are an example