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Glossary of Terms

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Jacket cells
Ciliated somatoderm of an orthonectide mesozoan.

Nucleopolyhedrosis of the silkworm Bombyx mori.

Liquid emitted from nozzle orifice.

Job costing
A system of costing which accumulates costs for each job separately.

Job grading
A job evaluation scheme based on an organisation's hierarchy of job grading.

Job ranking
A job evaluation scheme based on job descriptions.


Jointing stage
The stage when grass stems begin elongating.

Judgement sampling
The selection of a sample that, according to the judgement and intuition of the sampler, accurately reflects the population.

The observed phenomenon in harvested populations of a shift in the age structure toward a predominance of smaller animals.

Juvenile hormone
A chemical produced by the corpora allata, one of the three major insect development hormones, and responsible for determining the type of moult which will occur when one is directed by ecdysone. At high JH blood titre, additional larval or nymphal moults occur; low titre or complete absence of JH causes the pupal or imaginal transformation to occur.

Juvenile resistance
The characteristically vertical resistance of plants in the seedling stage; also known as seedling resistance

Juvenile stage
This term denotes any postembryonic stage in the development of an organism that precedes the sexually mature adult stage.

Condition in which tissues and organs remain immature.

Insect growth regulator that affects embryonic, larval and nymphal development e.g. methoprene.