That's all it does as the larval stage of the moth. I'm interested in the midgut. The pupal stage is the quiescent, developmental stage, while the moth is the sex stage.
Caterpillars grow quite rapidly.
At maximum caterpi1lar size it weighs about ten grams and is about three inches long, at which time it undergoes metamorphosis into a pupa. My research has two aims. The first is studying the developmental changes in the midgut, because we don't know what goes on inside the animal during larval-larval molting and metamorphosis to the pupa. I look at metabolism and active ion transport in the midgut, because the midgut not only digests and absorbs organic solutes, but it also has to transport a lot of inorganic ions. The other part of the developmental work is to look at what happens from the larval stage to the pupal stage, because at that stage the larval midgut is destroyed and replaced by a pupal midgut.