Deuterostomes

tissue layer

triploblasts

coelom

euceolomate

deuterostome meaning

mouth forms second

Phylum Echinodermata

spiny skinned animals - exclusively marine

echinodermata adults

mostly pentamerous and “secondarily” radially symmetric

echinodermata larva

bilateral

echinodermata endoskeleton

calcareous plates

echinodermata ciculatory system

open; no heart or blood

echinodermata excretory system

simple diffusion

starfish aboral surface

madreporite (entry of water into vascular system), mouth (extrude stomach through mouth)

starfish oral surface

anus and tube feet (locomotion, gas exchange, capturing prey and
excretion of wastes)

starfish ammonia waste elimination

primarily by diffusion across the epidermis and through the tube feet

echinodermata dermal papulae

fleshy projections of the body wall that increase surface area for gas exchange

echinodermata reproduction

diecious

how do sea urchins and sand dollars move

movable spines function in locomotion and defense

how do sea urchins and sand dollars feed

chewing structure called Aristotle’s lantern for grazing; composed of five calcareous teeth controlled by muscles

Chordata subphylum

Subphylum Cephalochordata
Subphylum Urochordata
Subphylum Chordata

Subphylum Urochordata

tunicates

tunicate feeding

filter-feeding adults with incurrent and excurrent siphons

tunicate movement

sessile

Chordata characteristics

notochord, dorsal hollow nerve cord, pharyngeal slits, and muscular post-anal tail

dorsal hollow nerve cord

precursor to the central nervous system; develops into the brain and spinal cord in some chordates

notochord

provides support during embryonic development and guides development of surrounding tissues, including the nervous system

pharyngeal (“gill”) slits

used for filter feeding in tunicates; modified into gills in fish; in tetrapods, contribute to structures of the throat and ear

muscular post-anal tail

present in most chordates; used for locomotion in many species, but reduced or lost in some chordates

tunicate larva

exhibit all four chordate characteristics, which are mostly lost in the adult

Subphylum Cephalochordata

lancelets

lancelets movement

free-living

lancelet feeding

burrowing filter feeders that use pharyngeal (gill) slits for feeding

lancelet chordate characteristics

Retain all four chordate characteristics throughout their lifespan

lancelet gas exchange

through skin

where does water exit from lancelets?

through the atriopore

Subphylum Craniata chordate traits

members possess them at some point in their lifespan

subphylum craniata neural crest cells

give rise to many craniate features

Subphylum Craniata skeleton

All species have a cranial skeleton, but most also possess a skeleton consisting of an axial skeleton and appendicular skeleton

axial skeleton

provides body support, sites for muscle attachment and facilitates locomotion

Subphylum Craniata
Class Myxini

hagfish: cranium + no vertebrae

subphylum craniata

class Petromyzontida

lampreys; cranium + rudimentary vertebral elements but no fully developed vertebral column

subphylum craniata Superclass Gnathostomata

craniates with jaws

subphylum craniata Class Chondrichthyes

sharks, skates and rays); cartilaginous cranium + skeleton

subphylum craniata Class Actinopterygii

ray-finned fish

subphylum craniata Class Sarcopterygii

lobe-finned fish

hagfish cranium

composed of cartilage; no vertebral column

hagfish feeding

scavengers/predators that often enter dead or dying fish and consume them from the inside out, using a rasping tongue (keratinous tooth plates) to draw food into a funnel-shaped mouth

hagfish defense

produce copious slime from specialized glands; the slime is a mixture of proteins and mucopolysaccharides that expands in water

subphylum craniata characteristics

cartilage and bone

superclass gnasthostoma (sharks, skates, rays) characteristics

jaws

clade Tetrapoda characteristics

4 limbs

clade amniota charecteristc

the amniotic egg

what taxon is the sister group to tetrapoda

lobe-finned fish

which group of craniates is the most diverse

ray-finned fish

which craniates lack a functional vertebrate

hagfish and lampreys