Blastopore develops into the mouth and the anus

develops later in the embryonic development

     -all exhibit bilateral symmetry and are triploblastic

     -all have an anterior concentration of nerve tissues

     -all have a ventral nervous system

 2 groups

     -lophotrochozoans

     -Ecdysozoans

Lophotrophzoans

(Protostome animal)

Have a ciliated U or O shaped feeding structure called a lophophore

     -Trochophore:larval form that uses cilia for locomotion

     -spiral cleavage

Phylm Bryozoa

(Lophotrochozoans, protostome animal)

 colonial animals that live in a house made of material excreted by the body wall

     -mostly marine

     -Asexual and sexual reproduction

Phylum platyhelminthes

(Lophotrochozoan, protostome animal)

 flatworms

     -triploblastic, acoelomate, bylaterally symmetrical animals

     -most are parasitic

     -2 way digestive system

Dorsoventrally flattened for diffusion of oxygen and carbon dioxide

Phylum Rotifera

(Lophotrochozoans,protostome animals)

 rotifers

triploblastic, acoelomate, bilaterally symmetric

     -complete digestive tract from mouth to anus

     -parthenogensis

mostly found in freshwater environments

Phylum Nemertea

(Lophotrochozoans, protostome animals)

 ribon worms

triploblastic, acoelomate, billaterally symmetric

     -mostly marine

feed using a hollow muscular proboscis

     -mouth to anus digestive tract

first to evolve a closed circulator system

Phylum Phoronida

(Lophotrochozoans, protostome animals)

triploblastic, coelomate, bilaterally symmetric

tube dwelling marine worms

     -chitin

extend lophophore from the tube to feed

Phylum Brachiopodia

(Lophotrochozoans, protostome animals)

marine animals that superficially resemble clams but valves are dorsal, not lateral

     -triploblastic, coelomate, bilaterally symmetric

     -Lophophore is located inside the shell

Phylum Annelida

(Lophotrochozoans, protostome animals)

segmented worms

triploblastic

     -body segmentation

     -closed circulatory system

     -degestive system:mouth to anus

Oligochaetes

(Phylum Annelidia, Lophotrochozoans, protostom animals)

 worms with chetael bristles made of chitin

     -e.g. earthworms aerate soils, and are hermaphrodites

                    -clitellum

Polychaetes

(Phylum Annelida,Lophotrochozoans, protostome animals)

 worms with parapodia on each body segment used for locomotion and/or gas exchange

     -mostly marine

     -burrowing animals

Leeches

(Phylum Annelida, Lophotrochozoans, protostome animals)

 parasites that suck blood from other organisms

     -antisthetics

     -anticoagulants

mostly freshwater

Phylum molluska

(Lophotrochozoans, protostome animals)

triploblastic, coelomate, billaterally symmetric

     -the most diverse group of lophotrochozoans

     -all have a foot, visceral mass and mantle open circulatory systems

Chitons

(phylum molluska, lophotrochozoans, protostome animals)

     -8 overlapping calcoreous plates

     -radula

bivalves

     -hinged shells

Gastropods

(phylum molluska, lophotrochozoans, protostome animals)

     -snails

     -slugs

     -nudibranches (seaslugs)

     -limpets

Cephalopods

(phylum molluska, lophotrochozoans, protostome animals)

     -squid

     -octopus

     -nautilus

Ecdysozoans

(protostome animals)

exoskeleton or cuticle

     -chitin

molting must occur for an organism to grow

     -instars

3 marine groups have relitively few species

     -priapulids

     -kinorhynchs

     -loriciferans

Priapulids

(ecdysozoan, protostome animals)

cylindrical wormlike animals (not segmented)

     -proboscis

     -trunk

     -caudal appendage (tail)

Kinorhynchs

(ecdysozoans, protostome animals)

microscopic animals that live in marine sediments

     -13 body segments

     -retractable proboscis

           -detritivores

Loriciferans

(ecdysozoans, protostome animals)

 microscopic animals that live in course marine sediments

     -discovered in 1983

     -head throax and abdomen

     -6 plates

Phylum Nematoda

(Ecdysozoans, protostome animals)

 roundworms

     -triploblastic

     -cuticle that sheds 4 times

     -longitudinal muscles only

digestive system is mouth to anus

     -can be parasitic or free living

parasitic roundworms can cause many diseases in plants and animals

     -elephantitasis

     -heatworms

Phylum Arthropodia

(ecdysozoans)

     -triploblastic, coelomate, bilaterally symmetrical

jointed pair appendages on each segment

     -specialized for varius functions

chitonous exoskeleton and open circulatory system

digestive system:mouth to anus

Ancestors of Arthropods

(Ecdysozoans, protistome animals)

velvet worms

     -unjoined appendages

tardigrades (water bears)

     -dormant state when dry

trilobites

     -first joined apendages

What are the 4 main groups of Phylum Arthropodia

(Ecdysozoans, protostome animals)

     -Myriapods

     -Chelicerate Atrhropods

     -Crustaceans

     -Hexapods

Myriapods

(Ecdysozoans, protostome animals)

centipedes

     -dorsoventrally flattened

     -1 pair of legs per body segment

     -predatory animals

Milipedes

     -not dosoventrally flattened

     -have fused segments, so each segment has 2 pairs of legs

     -mostly scavengers

Chelicerates

(ecdysozoans, protostome animals)

spiders, mites, ticks, scorpiona, harvestmen and horseshoe crabs

     -chelicerae:piercing feeding appendages

     -2 body segments

     -4 pairs of walking legs

Crustaceans

(ecdysozoans, protostome animals)

shrimps, crabs, lobsters, crayfish and barnacles

     -cephalothorax:head and thorax fused together

     -appendages have many different functions

           -antennae, chewing mandibles, walking, gas exchange

more species than any other groups of animals.

terrestrial and freshwater (very few marine)

     -evolution of flight

     -pollinators aided radiation of angiosperms

metamorphosis

     -incomplete:nymphs resemble adults

     -complete: nymphs look much differen from adults