Question

Retrogressive metamorphosis occurs in ____________ .

• A. Hemichordata
• B. Cephalochordata
• C. Urochordata
• D. Vertebrata

Answer 1

The correct option is C Urochordata

Metamorphosis is the phenomena in which there are changes which transform the organism from its juvenile stage to adult stage. In the case of retrogressive metamorphosis, the larva possesses the advanced features which get lost during the development. The adult is sedentary or degenerated with the primitive characters. Retrogressive metamorphosis is a characteristic of ascidians. They are from the group of Urochordates or Tunicates. The active and alert larva metamorphoses into a retrograde and sedentary bag-like creature. The adult remains attached to a rocky substratum.

Thus, the correct answer is option C.