What is the difference between chordates and non chordates?

S.No.

Features

Chordates

Non-Chordates

1.

Symmetry

bilateral

radial, biradial, bilateral or lacking

2.

Metamerism

true metamerism, where external segmentation is not clear

true or pseudometamerism, if true, external as well internal segmentation is clear

3.

Post anal tail

usually present

absent (except some)

4.

Organization

organ system grade

protoplasmic grade to organ system grade

5.

Germ layers

3 and hence triploblastic

2 or 3 and hence diploblastic or triploblastic

6.

Coelom

eucoelomate, (either enterocoelic or schizocoelic)

acoelomate, pseudo coelomate or eucoelomate

7.

Notochord

present at some stage of life

lacking

8.

Gut position

ventral to nerve cord

dorsal to nerve cord

9.

Nerve cord

hollow dorsal tubular, single non-ganglionated

solid, ventral, double, ganglionated

10.

Pharyngeal gill slits

present laterally on pharynx either throughout or only in embryonic stage

absent

11.

Blood vascular system

closed

open, closed or absent

12.

Heart

ventrally placed

dorsal, lateral or absent

13.

Dorsal blood vessel

blood flows posteriorly

if present, blood flows anteriorly

14.

Portal system

present

absent

15.

Respiratory pigment

haemoglobin in RBCs

present or absent, if present it is of various types in various animals, dissolved in plasma

16.

Respiratory organs

gills or lungs

body surface, tracheae, gills, book lungs, respiratory tree etc.

17.

Excretory organs

kidneys

flame cells, nephridia, green glands, coxal glands, Malpighian tubules, organs of Bojanus etc.

18.

Endoskeleton

living cartilagenous or bony endokskeleton

Endoskeleton (if present) is non living

19.

Digestive tract

complete

complete or incomplete

20.

Body temperature

cold or warm blooded

cold blooded

21.

Reproduction

predominantly sexual

predominantly asexual

22.

Regeneration power

usually poor

usually of high degree

23.

Cleavage

usually indeterminate (some exceptions)

usually determinate (some exceptions)

24.

Energy molecules for muscle contraction

creatine phosphate

arginine phosphate (except echinoderms)