The small choroidal vessels (mainly capillaries) that perforate the tapetum en route for the choriocapillaris can be viewed ophthalmoscopically as distinct dark dots the stars of Winslow.
Morphological aspect of tapetum lucidum at some domestic animals.
Moreover, it is reported that abnormal vacuolization of the tapetum during the tetrad stage was possible reason causing recessive GMS (Wan et al., 2010).
2, 3(I-II), the microsporangium wall of sterile anthers consisted of epidermis, endothecium, middle layer, and tapetum. It is shown that tapetal cells were large with condensed cytoplasm, several organelles, normal single nucleus and double nuclei, as well as large nucleus and conspicuous nucleolus (Fig.
The single cell layer of tapetum
surrounding the anther loculus is first recognizable at the early Microsporocyte stage .
Since the early days of orbicule-research, a positive correlation was hypothesised between the presence of orbicules and a parietal tapetum
type (von Ubisch, 1927; von Kosmath, 1927), although several species were identified with parietal tapetal cells but lacking orbicules (Huysmans et al., 1998).
The relatively large size of her eyes, the dense population of rods in her retina, and the tapetum
lucidum layer behind the retina are all adaptations aimed at maximizing night vision.
By the late sporogenous mass stage, when callose first appeared around the sporogenous cells, the tapetum
and parietal layer cells from male-sterile plants showed vacuoles (Fig.
Areas of pigmentation of retinal pigment epithelium overlying tapetum
were noticed in all seven pugs dogs especially near the tapetal- non tapetal junction.
When ascertaining tapetum
type, it is often necessary to examine several developmental stages of the anthers to avoid confusion.
There are two major types of tapetum
, the more primitive secretory type, considered to be the prevalent type in the majority of plants, and amoeboid type that extends to microspores in the anther locule .
In a recent overview Pacini and Franchi (1993) listed 33 species from 22 angiosperm families with secretory tapetum
and orbicules (references from 1971 to 1993).