In
insect physiology Insect physiology includes the physiology and biochemistry of insect organ systems.
Although diverse, insects are quite similar in overall design, internally and externally. The insect is made up of three main body regions (tagmata), the head, thor ...
and anatomy, the corpus allatum (plural: corpora allata) is an
endocrine gland
Endocrine glands are ductless glands of the endocrine system that secrete their products, hormones, directly into the blood. The major glands of the endocrine system include the pineal gland, pituitary gland, pancreas, ovaries, testes, thyroid ...
that generates
juvenile hormone Juvenile hormones (JHs) are a group of acyclic sesquiterpenoids that regulate many aspects of insect physiology. The first discovery of a JH was by Vincent Wigglesworth. JHs regulate development, reproduction, diapause, and polyphenisms.The chemic ...
; as such, it plays a crucial role in
metamorphosis
Metamorphosis is a biological process by which an animal physically develops including birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. Some inse ...
. Surgical removal of the corpora allata (an allatectomy) can cause an immature
larva
A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle.
The ...
to
pupate
A pupa ( la, pupa, "doll"; plural: ''pupae'') is the life stage of some insects undergoing transformation between immature and mature stages. Insects that go through a pupal stage are holometabolous: they go through four distinct stages in their ...
at its next
molt
In biology, moulting (British English), or molting (American English), also known as sloughing, shedding, or in many invertebrates, ecdysis, is the manner in which an animal routinely casts off a part of its body (often, but not always, an outer ...
, resulting in a miniature adult. Similarly,
transplantation of corpora allata from a young larva to a fully mature larva can greatly extend the larval stage, resulting in an equivalent to
gigantism
Gigantism ( el, γίγας, ''gígas'', "giant", plural γίγαντες, ''gígantes''), also known as giantism, is a condition characterized by excessive growth and height significantly above average. In humans, this condition is caused by ove ...
.
In many
Diptera
Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced ...
species, the corpus allatum is fused with the
corpus cardiacum Insect physiology includes the physiology and biochemistry of insect organ systems.
Although diverse, insects are quite similar in overall design, internally and externally. The insect is made up of three main body regions (tagmata), the head, thor ...
, forming a "ring gland", also known as
Weismann's ring.
In
Lepidoptera
Lepidoptera ( ) is an order (biology), order of insects that includes butterfly, butterflies and moths (both are called lepidopterans). About 180,000 species of the Lepidoptera are described, in 126 Family (biology), families and 46 Taxonomic r ...
species, the corpus allatum acts as a release site for
prothoracicotropic hormone Prothoracicotropic hormone (PTTH) was the first insect hormone to be discovered.The chemical symbol for prothoracicotropic hormone is (C64H102N16O19S2). It was originally described simply as "brain hormone" by early workers such as Stefan Kopeć (1 ...
which is generated by the brain.
''Insect Hormones''
page 13, by H. Fredrik Nijhout, 1994, Princeton University Press
References
Insect anatomy
Arthropod glands
{{Insect-anatomy-stub