echinoderm and Chordata

deuterostomes

branches off to Chordata and Echinodermata

for,atoin of the anus from blastopore  early human development

Echinoderms (a phylum)

includes sea stars and sea urchins

echino- spiny

derma-skin

nerve ring water vascular system

Chordates

Include the vertebrates but not alll are

Animals that at some stage have a notochord, gill slits, a dorsal nerve cord, and a post-anal tail.

Class Asteroidea

includes sea stars and sea daisies

scavenger feeders

Class Ophiuroidea

includes brittle stars

scavanger feeders

echinoidea

includes sea urchins and sand dollars

no arms but 5 rows of tubefeet

spines are used for locomotion and protection

Crinoidea

sea lillies

non moving

attach to coral reefs

Holothuroidea

sea cucumbers

lack spines and have 5 rows of tube feet

deuterostomes

branches off to Chordata and Echinodermata

for,atoin of the anus from blastopore  early human development

Echinoderms (a phylum)

includes sea stars and sea urchins

echino- spiny

derma-skin

nerve ring water vascular system

What is a chordata

The first thing to make one qualified to be a super phylum Chordata is to include the 4 main things:

Dorsal hallow nerve cord

Notochord (protects nerve cord)

Post anal tail

Pharyngeal gill slits

Invertebrates Chordata

Cephalochordate (lancelets) potential ancestor for invertebrates 

Urochordata(tunicates)

they still have a notocord

lack boney structure

jawless vertebrates

Myxini(hagfishes)

Petromyzontidia (lampreys)

primitive

Cartilage based fish

Chondrichthyes (sharks rays and chimaeras)

bony fish

Actinopterygii (ray finned fishes)

Lobed: Actinistia (coleacanths)

lobed: dipnoi (lungfishes

tetrapods (four legs)

amphibia (frogs and salamander)

Reptilia (turtles snakes crocolidles birds)

Mammalia (mammals)

Vertabrates (gnathostomes) or (jaw)

Chordates are considered vertebrates only when their notochord is replaced by a backbone made of bone or cartilage

Chondrichthyes, Actinopterygii, Actinistia, Dipnoi, Amphibia, Reptilia, Mamillia  

chordates vs vertebrates 

Chordates are considered vertebrates only when their notochord is replaced by bone or cartilage.

So chordates with no bones would be invertebrates because bones are the defining structure that differentiates the invertebrates from vertebrates. 

Vertabrata (craniata)

needs an enclosing spinal cord (doesnt need to be bone)

notochord needs to wrap the nerve cord 

in elaborate skull

fins rays