somes, fewer or greater than the multiple of the Haploid 

 (q. v.) number, cf. Euploid. 



Angiosperm 



The subdivision of Spermatophytes (seed-plants) in which 

 seeds are produced within the ovary, includes Monocotyle- 

 dons and Dicotyledons. 



Angle of Repose 



The maximum slope on which soil or loose rock remains 

 stable, syn. Critical slope. 



Anhydrous 



Refers to a substance that does not contain water, e.g. 

 anhydrous ammonia. 



Animal Unit 



A measure of converting kinds of livestock to a common 

 standard in relation to forage resources on the equivalent 

 of a mature cow (live weight of about 1000 pounds). One 

 animal unit in western range country equals about one head 

 of cattle, one horse, one mule, five sheep, five swine, or five 

 goats. 



Animal Unit Month 



A measure of forage or feed requirement to maintain 

 one animal unit for 30 days. 



Animation, Suspended 



Animals of simple organization such as some nematodes, 

 snails, and rotifers which can endure long periods of drying 

 in an inactive condition. 



Anion 



A negatively charged ion, e.g., chlorine, cf. Cation. 



Anisophylly 



The presence of two kinds of leaves on one plant as in 

 Selaginella and some junipers. 



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