KINGDOM ANIMALIA NON – CHORDATES CLASS 9

GENERAL FEATURES Eukaryotic Multicellular Heterotrophic No cell wall Mostly mobile

Two types Non – chordates or invertebrates Chordates or vertebrates

Porifera or sponges Organisms with holes or pores all over the body. Non motile animals – attached to some solid support. Canal system of circulation because of pores for circulating water throughout the body to bring in food and oxygen. Covered with hard outer or exoskeleton. Minimal differentiation and division into tissues. Marine habitats

sycon euplectela spongilla

Coelenterata (cnidaria) Live in water More body design differentiation Presence of a body cavity 2 layers of body cells – a layer outside the body and the inner lining of cells. Some species live in colonies like corals Others are solitary like hydra.

hydra corals Sea anemone Jelly fish

platyhelminthes More complex design of body. Bilateral symmetry of body – left and right halves of body have same design. Triploblastic – 3 layers of cells from which tissues are differentiated. This allows inside and outside body linings and some organs to be made. No coelom or internal body cavity. Called flatworms - Dorsiventrally flattened body ( flattened from top to bottom) Either free living (like Planaria) or parasitic (like liver fluke)

planaria Liverfluke tapeworm

nematoda elephantiasis Filarial worms Worms in intestine Bilaterally symmetrical Triploblastic Cylindrical body Tissues present, no real organs Pseudo coelom or a sort of body cavity is present. Parasitic worms causing diseases. Worms in intestine elephantiasis Filarial worms Worms in intestine Roundworm or pinworms

ascaris wuchereria

annelida Bilaterally symmetrical Triploblastic Have a true body cavity – true organs packaged inside the body – extensive organ differentiation. Body has segments lined up from head to tail. Habitats – freshwater, marine water, land

nereis earthworm leech

arthropoda Largest group of animals Bilaterally symmetrical Segmented body Open circulatory system – blood does not flow in blood vessels, blood fills the coelomic cavity Have jointed legs (arthro + poda)

Palamnaeus (scorpion) Pariplaneta (cockroach) Palaemon (prawn) Musca (housefly) Aranea (spider) Scolopendra (centipede) butterfly

mollusca Bilateral symmetry Coelomic cavity is reduced Little segmentation Open circulatory system Have kidney like organs for excretion Foot is used for moving around.

chiton pila Unio octopus

echinodermata In Greek, echinos means hedgehog, derma means skin. Spiny skinned organisms. Free living Marine Triploblastic Have a coelomic cavity. Tube system which is water driven for moving around. Skeleton made by hard structures made of calcium carbonate.

Antedon (Feather star) Holothuria (sea cucumber) Asterias (star fish) Echinus (sea urchin)

protochordata Bilaterally symmetrical Triploblastic Have a coelom Have a notochord at some stages of their life Notochord = long rod like structure that runs along the back of the animal separating the nervous tissue from the gut. Provides a place for muscles to attach for movement. Marine animals

Balanoglossus Herdmania Amphioxus