tapetum

(redirected from tapetal)
Also found in: Medical, Encyclopedia.
Related to tapetal: tapetum

ta·pe·tum

 (tə-pē′təm)
n. pl. ta·pe·ta (-tə)
1. Botany A nutritive tissue that surrounds certain developing spores, particularly the microspores within an anther.
2. 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.

[Medieval Latin tapētum, coverlet, from Latin tapēte, *tapētum, from Greek tapēs, tapēt-; see tapestry.]

ta·pe′tal (-pēt′l) adj.

tapetum

(təˈpiːtəm)
n, pl -ta (-tə)
1. (Botany) a layer of nutritive cells in the sporangia of ferns and anthers of flowering plants that surrounds developing spore cells
2. (Zoology)
a. a membranous reflecting layer of cells in the choroid of the eye of nocturnal vertebrates
b. a similar structure in the eyes of certain nocturnal insects
3. (Anatomy) anatomy a covering layer of cells behind the retina of the eye
[C18: from New Latin, from Medieval Latin: covering, from Latin tapēte carpet, from Greek tapēs carpet]
taˈpetal adj

ta•pe•tum

(təˈpi təm)

n., pl. -ta (-tə).
1. Bot. a layer of nutritive tissue in a developing sporangium or anther that is absorbed as the spore matures.
2. Anat. any of certain membranous layers or layered coverings, as in the choroid coat in certain animals.
[1705–15; < New Latin; Medieval Latin tapētum coverlet (Latin, only pl.) < Greek tapēt-, s. of tápēs carpet]
ta•pe′tal, adj.
References in periodicals archive ?
Large volume, dense cytoplasm and one or two large nuclei are evident in the tapetal cells at this point.
Ubisch bodies, (1) con-peito grains) are a-cellular structures of sporopollenin that might occur on the inner tangential and radial walls of tapetal cells.
Measurements from frontal sections rather than sagittal sections were used and the tapetal periphery was taken to represent the limits of the visual cells and therefore define the width of the retina.
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.
tissues of the seed parent, whereas interactive proteins in flowering plants are tapetal in origin.
In this stage, the tapetal cells are uninucleate and more vacuolated (Fig.
3h) indicates the occurrence of what are probably tapetal raphides, which also are known from other commelinaceous genera and several other related families (Hardy & Stevenson, 2000a, b; Hardy et al.
By the time the pollen grains are mature, the tapetal cells have completely degenerated, meanwhile the cells of middle layers grow radially and tangentially as the anther matures.
endosperm senescence) or sometimes individual cells (Pollen tapetal cells) (Delorme et al.
These are tapetal cells moved toward the microspores and extensions of them are visible in the anther locule at the microspores releasing stage (fig 2 E-F).
diameter that line the inner tangential and radial walls of the tapetal cells (Huysmans et al.
2000) stated that tapetal orbicules can be useful taxonomic markers at the tribal level.