preparation


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preparation

1. something that is prepared, esp a medicinal formulation
2. esp in a boarding school
a. homework
b. the period reserved for this
3. Music
a. the anticipation of a dissonance so that the note producing it in one chord is first heard in the preceding chord as a consonance
b. a note so employed
4. the preliminary prayers at Mass or divine service

Preparation

 

the making of animal and plant specimens, including fossils, for study.

To prepare organisms for anatomical study, animals are dissected, and plants are dismembered. The separate organs or organ systems are placed in fixative fluids. For making total preparations, animal organs are set right and stained, the circulatory and respiratory systems are filled with slightly jelling mastics or plastics, and, sometimes, sections are made of certain organs. If necessary, the organs are attached to a supporting plate. For plant preparation, longitudinal, radial, tangential, transverse, and superficial sections of organs are made. Skeletons and chitinous and limestone carapaces, as well as the conducting systems of plants, are freed from the soft tissues by maceration or by boiling in special solutions, such as caustic alkalies. Mammals, birds, and reptiles can be stuffed (taxidermy), and, in some cases, the skin coverings are dried and mounted. A special form of plant preparation is the mounting of an herbarium.

Microscopic preparation of objects (entire microorganisms, separate organs, organ parts, tissues, cells, intracellular formations, molecular and submolecular structures) involves a very exact procedure. A wide range of fixatives, stains, and reagents for dehydration, clarification, impregnation, and differentiated separation of the objects under examination is used. The making of temporary or permanent specimens involves enclosing the specially treated object between a microscope slide and a cover glass (seeMICROTECHNIQUE).

The preparation of fossil objects involves freeing them from their enclosing rock. The cleaned objects are then impregnated with various fixing substances and covered with special lacquers. Imprints of organisms on an enclosing rock (usually including fragments of organs) are fixed and preserved on parts of the rock.

REFERENCES

Prokhorov, M. G. Instruktsiia dlia raskopok, preparovki i montirovki iskopaemykh pozvonochnykh, 2nd ed. Leningrad, 1931.
Komarov, V. L. Prakticheskii kurs anatomii rastenii, 8th ed. Moscow-Leningrad, 1941.
Romeis, B. Mikroskopicheskaia tekhnika. Moscow, 1954. (Translated from German.)
Dal’, K. K. Posobie dlia rabotnikov anatomo-zoologicheskikh muzeev i kafedr biologii. Dushanbe, 1965.
Zaslavskii, M. A. Izgotovlenie chuchel, muliazhei i modelei zhivotnykh. Obshchaia taksidermiia. Leningrad, 1968.
Kukhtina, Zh. M. Rukovodstvo k prakticheskim zaniatiiam po tsitologii. Moscow, 1971.

O. L. ROSSOLIMO

References in classic literature ?
He had already locked up his safe, and made preparations for going home.
So far as one can ascertain from the conflicting accounts that have been put forth, the majority of them remained busied with preparations in the Horsell pit until nine that night, hurrying on some operation that disengaged huge volumes of green smoke.
Night came, and with it the preparation for departure, and these preparations served to conceal Dantes' agitation.
I never could endure this compound, and indeed the preparation is not greatly in vogue among the more polite Typees.
To such feelings delay, even the delay of much preparation, would have been an evil, and Mr.
Infadoos and the chiefs, however, were of opinion that no attack would take place that day, which would be devoted to preparation and to the removal of every available means of the moral effect produced upon the minds of the soldiery by the supposed magical darkening of the moon.
We were both so excited that, at the moment of greeting, neither of us could be apposite to the occasion in words, so we communicated our feelings by signs; as thus, David half sat down in a place where there was no chair, which is his favourite preparation for being emphatic, and is borrowed, I think, from the frogs, and we then made the extraordinary faces which mean, "What a tremendous adventure
After several months of preparation and an expenditure of a million dollars all was in readiness, and a series of tremendous explosions occurred on the earth and in the sky.
The author has in preparation an annotated anthology of poems from the popular ballads down, exclusive of long poems.
Days before she had been making preparations for the end, purchasing little stores for the boy's use, marking his books and linen, talking with him and preparing him for the change-- fondly fancying that he needed preparation.
The birth of a son (he was certain it would be a son) which was promised him, but which he still could not believe in--so marvelous it seemed--presented itself to his mind, on one hand, as a happiness so immense, and therefore so incredible; on the other, as an event so mysterious, that this assumption of a definite knowledge of what would be, and consequent preparation for it, as for something ordinary that did happen to people, jarred on him as confusing and humiliating.
Preparation by books had failed, owing to the doctor's infidel obstinacy.