What is metagenesis? Mention an example which exhibits this phenomenon.
Metagenesis is the phenomenon in which one generation of certain plants and animals reproduce asexually, followed by the sexually reproducing generation. Both the forms are diploid in metagenesis hence, it is the false alternation of generation.
Coelenterates exhibits metagenesis (e.g., Obelia) where polyp form alternates with medusa in its life cycle.