CLADE PHYLUM COMMON NAME HABITAT Parazoa NA NA Porifera Sponges pore bearers Mostly marine colonies Eumetazoa NA NA Cnidaria Hydroids Jellyfish Anenomes Corals bearing stingers Mostly marine Eumetazoa NA NA Ctenophora Comb Jellies Mostly marine Eumetazoa Protostome Lophotrochozoans Platyhelminthes Flateworms Marine Freshwater Terrestrial Eumetazoa Protostome Lophotrochozoans Nemertina Ribbon worms Mostly marine bottom dwellers Eumetazoa Protostome Ecdysozoa Nematoda Roundworms Eumetazoa Protostome Lophotrochozoans Rotifera NA Eumetazoa Protostome Lophotrochozoans Ectopracta Bryazoa Moss animals Terrestrial Aquatic free living Plants Animals parasites Mostly freshwater but few marine terrestrial epizoic or parasitic on molluscs earthworms protozoa Marine Freshwater Colonial of many zooids Freshwater bryozoans are not polymorphic all are of one type they each have feeding and reproductive functions unlike the Cnidarian Hydra Eumetazoa Protostome Ecdysozoa Annelida Marine Terrestrial Endoparasitic Segmented worms earthworms leeches Eumetazoa Protostome Ecdysozoa Arthropoda I Jointed Foot animals Found everywhere deep sea to mountain tops ORGANIZATION SYMMETRY BODY TYPES COELOM Cellular Level no true tissue Asymmetrical Asconoid Syconoid Leaconoid NA Tissue Level 2 germ layers diploblastic Radial Polyp Medusa ability to alternate NA NA Tissue Level 2 germ layers diploblastic Radial Medusa Organ Level 3 germ layers triploblastic Bilateral Generally small flattened Acoelomate Organ Level triploblastic Bilateral Flattened unsegmented Acoelomate the rhynocoel is lined with mesodermal tissuw but doesn t surround the gut is therefore not functionally equivalent to a coelom or pseudocoelom Therefore the nemertine body construction like flatworms is acoelomate Organ Level Bilateral Small in size Unsegmented tube w in a tube body plan Psuedocoelomate Organ Level Bilateral Psuedocoelomate Wheel animals ciliated corona beats like a rotating wheel 3 body sections head trunk foot Organ Level Bilateral Eucoelomate Freshwater bryozoans are not polymorphic all are of one type they each have feeding and reproductive functions unlike the Cnidarian Hydra Organ Level Bilateral Segmented metameres Eucoelomate Organ Level Bilateral Various types but all have exoskeleton Eucoelomate EMBRYONIC DEVELOPMENT SKELETON SUPPORT MOVEMENT LOCOMOTION 2 skeleton components spicules and structural protien matrix made of collagen spongin in the mesohyl None Sessile attached to a substrate cells removed from cells can regenerate after egg and sperm are produced and fertilized the stomoblastula inverts then becomes a amphiblastula free swimming then it attaches to a substrate to form a new colony Gastrulation ends at 2 germ layers and w an inconplete gut aka GVC Hydrostatic skeleton fluid filled GVC mesoglea Slow swimming circular longitudinal muscles or sessile Gastrulation ends at 2 germ layers and w an inconplete gut aka GVC Hydrostatic skeleton fluid filled GVC mesoglea Most are free swimming w rows of beating fused cilia Spiral cleavage Hydrostatic skeleton outer circular inner longitudinal muscles Hydrostatic skeleton outer circular inner longitudinal muscles act antagonistically Forward movement Spiral cleavage Hydrostatic skeleton outer circular inner longitudinal muscles Forward movement also have ciliated epidermal cells gland cells glide on mucus also have longitudinal circular muscles like flatworms they move by gliding over the substrate on a trail of slime using cilia and muscular contractions Spiral cleavage Thick cuticle to protect from digestive enzymes of host ie bile hydrostatic skeleton molting ONLY Longitudinal muscles Spiral cleavage Cuticle Hydrostatic skeleton Circular Longitudinal muscles sessile Radial cleavage BUT determinate Therefore protostome Epidermis secretes a gelatinous chitinous or caclium stiffened exoskeleton of many chambers each called a zoecium Cuticle Zooecium marine chitinous freshwater gelatinous also an inner hydrostatic skeleton Circular Longitudinal muscles sessile Spiral cleavage Development is either DIRECT young adult emerges or INDIRECT w ciliated trochophore larval stage Coelom s role for transporting nutrients is now diminished it NOW acts as just a hydrostatic skeleton marine polychaetes have acicula skeletal support muslce attachment Circular Longitudinal muscles in body wall allow metameres to move independently resulting in more complex variable forms of locomotion marine polychaetes have parapodia paddle like appendages w setae setae are chitinous bristles also on earthworms for anchoring and burrowing but not leeches Spiral cleavage Most exhibit metamorphosis a series of distinct post embryonic changes in body form eg larva to adult Hard outer exoskeleton hard chitinous cuticle that periodically molts NO hydrostatic skeleton Jointed appendages moved by antagonistic muscle pairs analogous to the vertebrate system SENORY NERVOUS DIGESTION FEEDING EXCRETORY OSMOREGULATION No specialized structures Filter feeders w intracellular digestion choanocytes have a collar of microvilli that trap food particles from flowing water that get engulfed by the cell passes on to other cells amoebocytes which can become sperm No specialized structure simple diffusion w environment water Nerve net rhopalia statocysts ocelli in scyphozoan medusae Extra intracellular digestion mouth GVC mostly carnivorous capture prey w tentacles nematocysts a stinging cnidum Diffusion Nerve net Similar to Cnidarians but no nematocysts but they have cells called a colloblasts to capter prey into the pharynx GVC Diffusion Concentration of sense organ in the anterioir end Cephalization Nerve net simple ladder like nervous system w anterior brain paired ganglia Incomplete Gut single opening mouth mid ventral pharynx simple intestine Partial extracellular digestion then phagocytosis intracellular digestion Tapeworms no digestive system NO GUT Protonephridia flame cells regulate water balance Diffusion metabolic nitrogen wastes Also have lateral tranverse nerve cords paired crebral ganglia Complete digestive tract mouth anus a 1st Also have a long eversible proboscis muscular tube not found in flatworms w a poison tipped stylet for capturing prey w in a rhynchocoel cavity which is located dorsal to the digestive tract serious predators carnivores of annelids small crustaceans Protonephridia regulate water balance But true excretory role now close to blood vessels so can eliminate N Ventral Dorsal nerve
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