Question

Give three major differences between chordates and non-chordates and draw a schematic sketch of a chordate showing those features.

Answer 1

Notochord:

Notochord is present in some stage of life, i.e., in embryo, larva or adult. Non-chordates do not have a notochord in any of the stages throughout their life.

Central nervous system:

Central nervous system is dorsal, single and hollow in chordates while it is ventral, double and solid in non-chordates.

Pharyngeal gill slits:

Pharynx is perforated by paired gills slits in chordates whereas gill slits are absent in non-chordates.

Diagram:




Final Answer:

Criteria	Chordates	Non-chordates
Notochord	Present in some stage of life, i.e., in embryo, larva or adult.	Absent throughout the life
Central nervous system	Dorsal, single and hollow	Ventral, double and solid
Pharyngeal gill slits	Pharynx is perforated by paired gills slits	Absent