J 1. Joining segment, q.v.
2. Joule, q.v.
Jiffy potTM Pots made from wood pulp and peat, commonly used for transplanting tissue-culture-derived plants into soil medium.
JIVET See juvenile in vitro embryo technology.
JIVT See juvenile in vitro embryo technology.
J/m2; J m-2 (joules per square metre) A unit of light measurement.
joining segment (J) A small DNA segment that links genes in order to yield a functional gene encoding an immunoglobulin.
joule (SI symbol: J) The amount of energy needed to apply a force of 1 newton over a distance of 1 metre.
jumping genes See transposable elements.
jumping library See chromosome jumping.
juvenility Early phase of development in which an organism is juvenile and incapable of sexual reproduction.
juvenile hormone A hormone secreted by insects from a pair of endocrine glands close to the brain. It inhibits metamorphosis and maintains the larval features.
juvenile in vitro embryo technology (JIVT; JIVET) A technology involving collection of immature ova from young animals, in vitro maturation of those ova, in vitro fertilization, and then transfer of the resultant embryos into recipient females. A method of achieving rapid generation turnover.