preformation


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Related to preformation: Preformation theory

pre·for·ma·tion the·o·ry

archaic theory that the embryo was fully formed in miniature within a gamete at the time of conception.
See also: homunculus. Compare: epigenesis.

preformation

(prē′fôr-mā′shən)
n.
1. The act of shaping or forming in advance; prior formation.
2. A theory popular in the 1700s that all parts of an organism exist completely formed in the germ cell and develop only by increasing in size.

preformation

[-fôrmā′shən]
Etymology: L, prae + formatio, formation
an early theory in embryology in which the organism is contained in minute and complete form within the germ cell and after fertilization grows from microscopic to normal size. Compare epigenesis.

preformation

(prē-fawr-mā′shŭn)
In embryology, the development of structures from pre-existing templates, e.g., of bones from cartilage templates.
References in periodicals archive ?
Likewise, because Godwin rejects preformation as a kind of institution, one might see perfectibility as closer to epigenesis, which describes the progressive development of an embryo out of the amorphous flux of an egg cell, or in Godwin's Lockean terms, the emergence of the mind from its originary state as "an unfinished sketch" through a process of division and self-differentiation (PJ 1798, 1:36).
Erasmus Darwin, grandfather of Charles and a proponent of preformation, held "that the embryon is produced by the male, and the proper food and nidus by the female.
In this context of the question of interpretation, it is relevant that The Prelude is, among other things, a particularly strong instance of a literary work that double-times as the story of the genesis of its own poetical achievement, and therefore as a preformation of its own interpretation (and its demise in the rest of Disgrace should warn against a repetition of this configuration in the case of Coetzee's autobiographies).
simple machine Time automatic machine Time 1 Thermal gluing of the 0,36 Thermal gluing of the 0,36 insertion in the sewing insertion in the sewing zone zone 2 Marking of the pocket 0,56 Positioning of the 0,18 position details 3 Application of the 2,4 Fixing the details and 0,35 insertion and preforming the pipe preformation of the pipe 4 Sewing the pocket 1,2 Sewing the pocket 0,40 5 Cutting the opening 1,3 Cutting the opening 0,18 Total 5,82 Total 1,47
Stone, Prebis, and others asserting that they mismanaged Thomas' medical condition and failed to diagnose abdominal abscesses, which resulted in preformation of his colon.
Otherwise, the partisans of the theory of preformation claim that every organism is completely predetermined in its germ.
This assumption, coupled with religious commitments, led to the competing theories of preformation and epigenesis.
The cord construction design parameters, such as the number of filaments, the filament diameters, lay lengths and directions, as well as the preformation type and degree are important to determine the cord geometry for good rubber penetration.
Each in turn examined the theory of preformation in the light of natural philosophy and religion.
By observing the instructional lineages across five consecutive, cumulative, and cyclical formation periods (namely, preformation, information, transformation, uniformation, and conformation/reformation/deformation), seven information flows can be quickly sketched and displayed in parallel to show the vertical and horizontal interrelationships of the four twisting-bonding/clipping-jointing subforces that constantly cooccur in the invisible form of the Q-T-S-C Chain.
The NAIB recommends that those selling ownership interests in risk retention groups should be specifically exempted from a requirement to be a licensed securities broker-dealer and specifying that all preformation promotional activities are covered by securities law exemptions.
They reveal no cumulative abnormal return for either the preformation sub-period or the post-formation one.