The upcoming discussion will update you about the difference between non-chordates and chordates.
Difference # Non-Chordates:
1. Body with bilateral or radial symmetry.
2. The paired appendages vary in number and may even respond to the number of body segments.
3. Tail absent.
ADVERTISEMENTS:
4. Branchial clefts absent.
5. The vascular system is open and consists of a heart, arteries and sinuses, the last ones are continuation of primary body cavity.
6. The heart is less muscular, dorsal and always above the alimentary canal.
7. No portal veins.
ADVERTISEMENTS:
8. The respiratory pigment haemocyanin is a prosthetic group of copper or haemoglobin in some cases. Both are dissolved in plasma.
9. Notochord absent.
10. The main nerve cord is a solid, double one, running mid-ventrally immediately dorsal to the ventral body wall.
Difference # Chordates:
1. Body bilaterally symmetrical.
ADVERTISEMENTS:
2. The appendages are two pairs.
3. A post-anal tail is usually present.
4. The branchial clefts are always present, being restricted to larval stages only in some.
5. The vascular system is a closed one and consists of a heart, arteries and veins.
6. The heart is highly vascular, ventral and lies below the alimentary canal.
7. Portal veins present in the majority.
8. The respiratory pigment haemoglobin is an iron compound and present in the erythrocytes.
9. A solid, un-segmented, flexible axial rod, the notochord is universally present and extends along the whole body length.
10. The spinal cord is a hollow, mid-dorsal tube, placed immediately below the body wall and above the notochord.