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The semisolid external layer of protoplasm in some unicellular organisms, as the amoeba; ectoplasm; exoplasm.

That branch of biology which treats of the electrical phenomena of living organisms.

A method of determining the presence or absence of life in an animal organism with a current of electricity, by noting the presence or absence of muscular contraction.

rical results produced through physiological agencies, or by change of action in a living organism.

The theory that the functions of living organisms are dependent upon electricity or a kindred force.

f the simplest essential parts, more commonly called cells, of which animal and vegetable organisms, or their tissues and organs, are composed.

a clot of fibrin, a detached shred of a morbid growth, a globule of fat, or a microscopic organism.

The first rudiments of an organism, whether animal or plant; as:

The semifluid, granular interior of certain unicellular organisms, as the inner layer of sarcode in the amoeba; entoplasm; endoplasta.

The process by which animal and vegetable organisms preserve a physiological balance. H. Spenser.

A general name for the history of the steps by which any living organism has acquired the morphological and physiological characters which distinguish it; a gradual unfolding of successive phases of growth or development.

The property manifested by living organisms, and the elements and tissues of which they are constituted, of responding to the action of stimulants; irritability; as, nervous excitability.

gent or influence which arouses vital activity, or produces increased action, in a living organism or in any of its tissues or parts; a stimulant.

To call forth or increase the vital activity of an organism, or any of its parts.

A state of aroused or increased vital activity in an organism, or any of its organs or tissues.

A groupe of organisms, either animal or vegetable, related by certain points of resemblance in structure or development, more comprehensive than a genus, because it is usually based on fewer or less pronounced points of likeness. In zoölogy a family is less comprehesive than an order; in botany it is often considered t…

which, either in animals or plants, material prepared by the generative organs the female organism is brought in contact with matter from the organs of the male, so that a new organism results; impregnation; fertilization.

lity or power of producing fruit; fruitfulness; especially (Biol.), the quality in female organisms of reproducing rapidly and in great numbers.

ents, and enzymes. Ferments of the first class are as a rule simple microscopic vegetable organisms, and the fermentations which they engender are due to their growth and development; as, the acetic ferment, the butyric ferment, etc. See Fermentation. Ferments of the second class, on the other hand, are chemical substa…

A method of asexual reproduction among the lowest (unicellular) organisms by means of a process of self-division, consisting of gradual division or cleavage of the into two parts, each of which then becomes a separate and independent organisms; as when a cell in an animal or plant, or its germ, undergoes a spontaneous…