Sponges

• Asexual reproduction or sexual egg laying
• Have sharp spicules and chemical toxins 
• Have osculum central opening that water moves out
• assmmetric, maily marine with a few fresh water
• sessile, with two cell layers surrounding acentral cavity
  

• only a single names species, Trichoplax adhaerens.
• Wide spread in tropical ocean, little is know about them
• two layers of ciliated epithelial cells, absorbs food through them
• no symmetry, mouth, nerves, tissue, or organs
• genome suggest it belongs between Porifera and Cnidaria
• sexual behaviors have never been seen
• discovered in 1880 in a marine fishtank

• only true radially symmetrical animals
• hydras, sea anemones, jellyfish, corals
• ectoderm and endoderm, and mouth at one end
• anterior and posterior axis
• floating medusae (jellyfish) and anchored polyps (hydras) or a life cycle displaying both
• embryos undergo gastrulation
• have stinging nematocysts (feeding and defense)
• reproduce sexually, or asexually by budding

• comb jellies
• resemble cnidaria with mesoglea but are: smaller, more fragile, rarer, mostly marine, lack nematocysts, and never sessile
• swim by beating cillia
• form a third layer of embryotic tissue, mesolea, resembling mesoderm
• not quite radially symmetrical

• flatworms 
• Protostome
• clear layer of mesoderm (beteen ectoder and endoderm) gives rise to internal organs including excretory system and muscles
• well developed nervous system(ectodermal tissue), concentration of sensory system for touch, smell, primitive sight (cephalization)
• blind gut, no anus, no body cavity, no circulatory system, breath through body wall
• acoelomates (no coelom body cavity)
• elaborate hermaphrodite reproductive system (sexual, transfer sperm between partners)
• three major classes Tuvellaria (turbellarians), Trematoda (flukes), and Cestoda (tapeworms)
  

• round worms
•  20,000 known species inhabiting all imaginable habitats
  
• organs formed of mesoderm, pseudocoelom
• hard outer cuticle
  
• cause filariasis (mosquito) by replicationo in our bloodstream/lymph nodes

Phylum Nemertea

• ribbonworms
• entirly marine, long, flat, colorful
• pretetors using proboscis
• complete gut
• mouth from blastopore
• anus from secondary invagination (posterior end)

• Wheel animals
• tiny (2mm long)
• pseudocoelom body cavit, similar to worms
• not positive of where fit phylogenetically
• ring of eating cilia around the mouth, eat bacteria, protists and single celled algae

• slow walkers
• tardigrades water bears
• resist desicction
• tiny less than 2mm,live in moist places (mosses)

• four major classes (chitons, gastropoda, bivalvia, Cephalopoda)
• unsegmented
• muscular foot
• visceral mass containing internal organs
• mantle, tissue draping over visceral mass
• shell, the mantle secretes
• mantle cavity water-filled housing gills and anus
• radula, mouth contains unique rasping organ (scrapping)

• segmented worms
• three classes, polychaetes, Oligochaetes, Hirudina

• segmented velvet worms
• moist terrestrail enviroments
• voracious hunters (gooey spit)
• Australia, south america, africa
• support Gondwanaland (one body of land)
• Ecdysozoa

• jointed legs
• hardened exoskeletons, repeatedly molt
• the largest phylum
• marine and terrestrial
• 5 classes, Trilobites, Chelicerates, miriapods, crustaceans, insects

• totally marine
• sea stars, sea urchins, brittle stars, sand dollars and sea cucumbers
• adults show penta-radial symmetry (five roughly equivalent axes)
• larve have bilateral symmetry
• tube feet, spicules, spines, plates
• deuterostomes
• mineralization of some armor/skeletal features
• no cephalization (secondary loss or never evolved)
  

• notochord (derived mesoderm, rod supporting length of body)
• tubular dorsal nerve cord, dervied mesoderm, parallel to notochord and gut
• pharynx, muscular tube dervied from mesoderm funcitons in feeding/repiration
• tail extends past the anus
• three subphyla, Urochordata, cephalochordata, vertebrata
• humans