Which characteristic feature differentiates Urochordata from Cephalochordata?
In Urochordates (e.g., Ascidia), the notochord is present only in the larval stage, whereas in Cephalochordates (e.g., Branchiostoma), it is present throughout life.
Ref: NCERT Class 11 Biology Chapter 4: Animal Kingdom Phylum Hemichordata and Chordata - Protochordata