Invagination
Invagination is the infolding of one part within another part of a structure,[1] a folding that creates a pocket.[2] The term, originally used in embryology, has been adopted in other disciplines as well.
Biology
- Invagination is the morphogenetic processes by which an embryo takes form, and is the initial step of gastrulation,[3] the massive reorganization of the embryo from a simple spherical ball of cells, the blastula, into a multi-layered organism, with differentiated germ layers: endoderm, mesoderm, and ectoderm. More localized invaginations also occur later in embryonic development,
- The inner membrane of a mitochondrion invaginates to form cristae, thus providing a much greater surface area to accommodate the protein complexes and other participants that produce adenosine triphosphate (ATP).[4]
- Invagination occurs during endocytosis and exocytosis when a vesicle forms within the cell and the membrane closes around it.
- Invagination of a part of the intestine into another part is called intussusception.[5]
Humanities
The term is used to explain a special kind of metanarrative. First used by Maurice Merleau-Ponty[6] to describe the dynamic self-differentiation of the 'flesh'. Used by Rosalind Krauss and Jacques Derrida (The Law of Genre, Glyph 7, 1980). For Derrida, an invaginated text is a narrative that folds upon itself, "endlessly swapping outside for inside and thereby producing a structure en abyme".[7] He applies the term to such texts as Immanuel Kant's Critique of Judgment[7] and Maurice Blanchot's La Folie du Jour.[8] Invagination is an aspect of différance, since according to Derrida it opens the "inside" to the "other" and denies both inside and outside a stable identity.[2]
Geology
In geology, invagination is used to describe a deep depression of strata. Used by Donald L. Baars in "The Colorado Plateau".
References
- ↑ "Medical Dictionary".
- 1 2 Wortham, Simon Morgan (2010). The Derrida Dictionary. Continuum International. p. 76. ISBN 9781847065261. Retrieved 12 January 2013.
- ↑ Alberts (2002). Molecular Biology of the Cell. New York: Garland Science.
- ↑ Cronk, Jeff. "Biochemistry Dictionary".[dead link]
- ↑ Blanco, Felix. "Intussusception". Retrieved 1 November 2012.
- ↑ Merleau-Ponty, Maurice (1968). The Visible and the Invisible. Boston, MA: Northwestern University Press. p. 152. ISBN 0810104571.
- 1 2 Chaplin, Susan (2004). Law, Sensibility, and the Sublime in Eighteenth-Century Women's Fiction: Speaking of Dread. Ashgate. p. 23. ISBN 9780754633068. Retrieved 12 January 2013.
- ↑ Jones, Amelia (2003). The Feminism and Visual Culture Reader. Psychology Press. p. 200. ISBN 9780415267069. Retrieved 12 January 2013.