Presvlačenje i metamorfoza u kukaca

Insects have to moult because their cuticle prevents their growth. Regarding types of metamorphosis, insects can be ametabolous, hemimetabolous or holometabolous. Most influential glands for moulting and metamorphosis are the brain, corpus cardiacum (CC), prothoracic gland and corpus allatum (CA). The prothoracic gland secretes ecdysteroids which are responsible for moulting. The CA secretes juvenile hormone (JH) in the absence of which the metamorphosis starts. An adult insect is developed during metamorphosis. Organs characteristical for adults, such as wings or antennae, are developed from imaginal discs. Adult insects are fertile and no longer moult, except in cases of ametabolous insects and hormonal disorders.