Question

Ascidian tadpole and retrogressive metamorphosis

Answer 1

Metamorphosis is a change from the juvenile to adult stage in which the tadpole larval stage is quite different from the adult stage.
In retrogressive metamorphosis the larva possesses advanced characters which are lost during the development and the adult is either sedentary or degenerated with primitive characters.

Answer 2

So during metamorphosis. ... Such type of metamorphosis is called " Retrogressive ... It is characteristic of ascidians.
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