Porifera With pores, sessile, asymetric, diploblastic Cells- outer pinacoderm, middle- amoebocytes and inner-choanocytes Skeleton- spicules and spongin fibres Water canal system Eg: Sycon, Spongilla ( Fresh Water sponge), Euplectella ( Glass sponge)

Phylum Cnidaria

General Characteristics They are radially symmetrical; oral end terminates in a mouth surrounded by tentacles. They have 2 tissue layers Outer layer of cells - the epidermis Inner gastrodermis, which lines the gut cavity or gastrovascular cavity (gastrodermis secretes digestive juices into the gastrovascular cavity) In between these tissue layers is a noncellular jelly-like material called mesoglea

Cnidarian Body Plans Polyp form Tubular body, with the mouth directed upward. Around the mouth are a whorl of feeding tentacles. Only have a small amount of mesoglea Sessile Medusa form Bell-shaped or umbrella shaped body, with the mouth is directed downward. Small tentacles, directed downward. Possess a large amount of mesoglea Motile, move by weak contractions of body

Nutrition Cnidarians are carnivores with hydras and corals consuming plankton and some of the sea anenomes consuming small fishes They use they tentacles to capture prey and direct it toward the mouth so that it can be digested in the gastrovascular cavity via secretions from gland cells (extracellular digestion); some food is phagocytized by special cells and digestion occurs intracellularly The gastrovascular cavity exists as 1 opening for food intake and the elimination of waste There is no system of internal transport, gas exchange or excretion; all these processes take place via diffusion

Alternation of generation Mouth or hypotostome present Ctenophora: Comb jellies diploblastic, tissue level organisation An outer epidermis, mesoglea with amoebocytes, and An inner gastrodermis Colloblasts- on epidermis of tentacles- for prey capture locomotion- cilia with comb plates for nutrition Eg: Ctenoplana Hormephora

Platyhelminthes: Flat worms unsegmented, bilateral symmetry, triploblastic Acoelomate, organ system level of organisation Suckers and hooks for holding the intestine of host Incomplete gun – only mouth present, no anus Excretion- Flame cells Regeneration capacity high in Planarians Eg; Taenia solium, Fasciola hepatica

NEMATHELMINTHES - Round worms / thread worms Bilateral symmetry, Triploblastic , pseudo coelomate Alimentary canal- complete with muscular pharynx No respiratory and circulatory system muscles- Circular and longitudinal Sex- seperates; male shorter than female Fertilisation – internal Ascaris, Wuchereria, Ancylostoma ( Hook worm)

Annilida : Annullus: little ring Triploblastic, bilateral symmetry, coelomate Metamerism Muscles- longitudinal and circular Digestion – complete Excretion- nephridia; circulation- closed Some are bisexual Development- indirect through Trocophore larva Eg; Pheritima, Tubifex ( blood worm), Neries

Arthropoda Body – Head, thorax and abdomen Jointed appendages, antennae, eyes ( ommatidia) and statocysts Digestive system is complete Chitin ; undergoes Ecdysis/ moulting Respiration- Gills/ trachea/ Book lungs/ / Book Gills Excretion- Malphigian tubules/ nephridia Fertilisation- internal , oviparous Apis , Bombyx, Laccifer, Anopheles, culex, locusts, Limulus

Mollusca ( soft body) Body- Head, Visceral mass , muscular foot Radula- rasping organ Body wall – with mantle- secretes shell Digestion – complete; excretion- nephridia Unisexual, external fertilisation, oviparous Indirect development- Veliger, trocophore and Golchidium larvae

Echinodermata Endoskeleton- calcarious plates with spines larvae- bilateral sym and adults- radial sym Water vascular system with tube feet, radial canals– excretion, circulation High regeneration capacity development- indirect: Plateus, bipinnaria and auricularia

Hemichordata Body- Proboscis, collar and trunk proboscis- Ciliated for collecting food Mouth- between proboscis and collar Stomochord- similar to notochord Excretion- proboscis gland Reproduction- sexual, dev- indirect ( tornaria)

Chordata Protochordata Includes tunicates ( urochordates) and Cephalochordates Tunicates- notochord and nerve chord present only in larva Cephalochordates- nerve chord and notochord persistant Vertebrata Notochord replaced by vertebral column Respiration – gills/lungs Circulation – closed -Includes Agnatha and Gnathosomata