Search the Dictionary

The power possessed by living organisms, both animal and vegetable, of adapting themselves to modifications or changes in their environment, thus possibly giving rise to ultimate variation of structure or function.

es and acting in exceedingly minute quantities, by which a disease is introduced into the organism and maintained there.

The doctrine that all the functions of a living organism are due to an unknown vital principle distinct from all chemical and physical forces.

A genus of minute, pale-green, globular, organisms, about one fiftieth of an inch in diameter, found rolling through water, the motion being produced by minute colorless cilia. It has been considered as belonging to the flagellate Infusoria, but is now referred to the vegetable kingdom, and each globule is considered a…

es, to wear away, or alter, under atmospheric influences; to suffer waste by weather. The organisms . . . seem indestructible, while the hard matrix in which they are imbedded has weathered from around them. H. Miller.

The fancied production of an organism of one kind by an organism of another. Huxley.

a conveniently transportable substitute for yeast. -- Yeast plant (Bot.), the vegetable organism, or fungus, of which beer yeast consists. The yeast plant is composed of simple cells, or granules, about one three-thousandth of an inch in diameter, often united into filaments which reproduce by budding, and under cert…

Symmetrical bilaterally; -- said of organisms, or parts of organisms, capable of division into two symmetrical halves only in a single plane.

Capable of producing a definite zymogen or ferment. Zymogenic organism (Biol.), a microörganism, such as the yeast plant of the Bacterium lactis, which sets up certain fermentative processes by which definite chemical products are formed; -- distinguished from a pathogenic organism. Cf. Micrococcus.…

ndemic, contagious, or sporadic affection which is produced by some morbific principle or organism acting on the system like a ferment.