tapetum

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tapetum

 [tah-pe´tum] (L.)
1. a covering structure or layer of cells.
2. a stratum in the human brain composed of fibers from the body and splenium of the corpus callosum sweeping around the lateral ventricle.
tapetum lu´cidum the iridescent epithelium of the choroid of animals that gives their eyes the property of shining in the dark.

ta·pe·tum

, pl.

ta·pe·ta

(tă-pē'tŭm, -tă), [TA]
1. In general, any membranous layer or covering.
2. neuroanatomy a thin sheet of fibers in the lateral wall of the temporal and occipital horns of the lateral ventricle, continuous with the corpus callosum. Synonym(s): Fielding membrane, membrana versicolor
3. A dense layer in the choroidea of the eye of many mammalian species, including the cat and dog but not humans, which forms a discrete or diffuse area of reflective cells, rodlets, and fibers; its strong light-reflecting properties cause the metallic hue and light-glow of such eyes in the dark.
[L. tapeta, a carpet]

tapetum

(tə-pē′təm)
n. pl. tape·ta (-tə)
Anatomy
a. A reflective membrane in the back of the eye of many animals that are active during low-light conditions.
b. A layer of fibers of the corpus callosum forming the roof of part of the lateral ventricle of the brain.

ta·pe′tal (-pēt′l) adj.

ta·pe·tum

, pl. tapeta (tă-pē'tŭm, -tă) [TA]
1. In general, any membranous layer or covering.
2. [TA] neuroanatomy A thin sheet of fibers in the lateral wall of the temporal and occipital horns of the lateral ventricle, continuous with the corpus callosum.
[L. tapeta, a carpet]

tapetum

  1. a nutritive layer surrounding those cells which will become MICROSPORES. The tapetum is found in a wide range of vascular plants, from FERNS to ANGIOSPERMS. In the latter, a tapetal layer is found in the pollen sacs of the ANTHER.
  2. a layer of specialized reflective cells in the choroid of the EYE, especially noticeable in the eyes of cats.

Fielding,

George H., English anatomist, 1801-1871.
Fielding membrane - in neuroanatomy, a thin sheet of fibers in the lateral wall of the temporal and occipital horns of the lateral ventricle, continuous with the corpus callosum. Synonym(s): tapetum
References in periodicals archive ?
In Arabidopsis, the acyl-CoA synthetase gene ACOS5 was upregulated in the tapetal cells.
Fundus photographs after 8 hours of patching revealed Mizou Nakamura phenomenon which is characterized by loss of the golden sheen and tapetal reflex after prolonged dark adaptation (fig-1) OCT (Topcon 3D OCT-1 Maestro) showed normal central foveal thickness but reduced retinal thickness in parafoveal region (fig-2).
The retinal edema can be generalized or local, mainly in the tapetal zone (Sharma, Kanaujia, Mishra, Agarwal, Tripathi et al., 2013).
One of the few papers devoted to fossil orbicules and tapetal membranes is the ultrastructural work on fossil Pennsylvanian (Carboniferous, 286-320 mya) pollen grains of the Schopfipollenites-type (Taylor, 1976).
The visual cells in these eyes bend around the tapetum, exiting through the opening between the adjacent tapetal plates.
Leaf removal could have led to an effect on the amount, and perhaps quality, of the secretion of the tapetal cells that nurtures the immature pollen grains, resulting in the difference in size we observed between the pollen produced by control and defoliated shoots.
The images were evaluated and characterized according to its breed which included a) Tapetal color b) Tapetal reflectivity c) Shape of tapetal area d) Homogenicity of tapetum e) The junction of tapetal and non tapetal border.
At about the time the pollen tetrad appears, the walls of the tapetal cells become indistinct, and the tapetal cells degenerate at their original site.
(2010) studied the molecular mechanism of HMGS involved in development of tapetum-specific organelles and fertility of pollen grains, and found that the MVA pathway is essential for development of both tapetosomes and elaioplasts in tapetal cells and for pollen viability, at least during pollen tube elongation.
At the stage of anther dehiscence, there was one-layer anther wall of endothecium and the tapetal layer was digested completely (Fig1 Q) to nourish the pollen grains.
A oftalmoscopia, observa-se atenuacao vascular, palidez de papila, hiperreflexia da area tapetal pelo afinamento da retina e despigmentacao da area nao-tapetal.
As emphasized by von Aderkas and Prior (submitted) the pollination drop is a structure of great chemical complexity However, these proteins originate from sporophytic (nucellar?) tissues of the seed parent, whereas interactive proteins in flowering plants are tapetal in origin..