How many distinct stages are involved in the gradual metamorphosis of insects?

Insects that undergo gradual metamorphosis experience three distinct stages: the egg, the nymph, and the adult. This type of metamorphosis is characterized by the absence of a distinct pupal stage, which sets it apart from complete metamorphosis, where insects typically transition through four stages: egg, larva, pupa, and adult. The nymph stage resembles a smaller version of the adult but lacks fully developed wings and reproductive organs. As the nymph matures, it undergoes a series of molts, growing larger and developing these adult characteristics. This process highlights the gradual changes in form and function that occur as the insect progresses to maturity, making it an essential feature of the life cycle for certain insect groups.