juvenile hormonemedical dictionary

<endocrinology> A hormone found in insects which affects the balance between mature and juvenile attributes of certain tissues at each moult. In particular, the imaginal discs of many larval insects only develop into adult wings, sexual organs or limbs when blood juvenile hormone levels fall below a threshold level. There is a complex interaction between juvenile hormone and ecdysone. Synthetic analogues of JH include farnesol and methoprene, which have been tested for insecticide potential (known, with diflubenzuron, as Insect Growth Regulators, IGRs.

See: chitin).

(11 Mar 2008)