Difference Between Chordates and Non-Chordates
The difference between Chordates and non-chordates are as follows:
Features | Chordates | Non-Chordates |
---|---|---|
Notochord | Present at some stage; replaced by the vertebral column | Absent |
Symmetry | Bilateral or radial | Radial, bilateral, or asymmetrical |
Body temperature | Can be cold-blooded or warm-blooded | Cold-blooded |
Coelom | True coelomates | Can be acoelomates, pseudocoelomates, or coelomates |
Germ Layer | Triploblastic | Diploblastic or Triploblastic |
Level of Organisation | Organ system | Protoplasmic to organ system |
Post-anal tail | Present for body balancing | Absent |
Skeleton | Endoskeleton present in all; exoskeleton in some | Exoskeleton present; endoskeleton absent |
Regeneration | Poor | Good |
Digestive system | Complete or incomplete | Often incomplete |
Position of Gut | The gut is present ventral to the nerve cord. | The gut is present dorsal to the nerve cord. |
Anus | Anus is differentiated and opens before the last segment. | Anus is generally absent. If present, it opens on the last segment. |
Respiration | Aquatic species use gills; terrestrial use lungs | Diffusion across the body surface |
Gill Slits | Pharynx is perforated by gill slits. | Gill Slits are absent |
Circulatory system | Can be closed or open | Open circulatory system or no circulatory system |
Heart | Ventral side | Absent or dorsally or laterally placed if present |
Blood | Blood is red in colour due to the presence of hemoglobin. | Blood is colorless due to the absence of hemoglobin and is known as hemolymph. |
Nerve cord | Single, dorsal nerve cord without ganglia | Double, ventral nerve cord with ganglia |
Brain | Present dorsal to pharynx in the head | Present in some, but not as complex as in chordates |
Examples | Tunicates, lancelets, vertebrates | Insects, mollusks, worms, jellyfish, and others |
Difference Between Chordates and Non Chordates
Difference between Chordates and Non-Chordates: Chordates and Non-Chordates are two groups of animals based on the presence or absence of a notochord. Notochord is a flexible rod-like structure that provides support. Chordates possess a notochord at some stage of their life. Non-chordates, on the other hand, lack a notochord. In this article, we will cover key distinctions between chordates and non-chordates in detail.