scholarly journals THE FINE STRUCTURE OF EPENDYMA IN THE BRAIN OF THE RAT

1963 ◽  
Vol 19 (2) ◽  
pp. 415-439 ◽  
Author(s):  
M. W. Brightman ◽  
S. L. Palay
Keyword(s):  
Fine Structure ◽  
Basal Body ◽  
Intercellular Space ◽  
Proximal Region ◽  
Luminal Surface ◽  
Zonula Occludens ◽  
Dense Bodies ◽  
Body Complex ◽  
Basal Foot ◽  
The Brain

The ciliated ependyma of the rat brain consists of a sheet of epithelial cells, the luminal surface of which is reflected over ciliary shafts and numerous evaginations of irregular dimensions. The relatively straight lateral portions of the plasmalemma of contiguous cells are fused at discrete sites to form five-layered junctions or zonulae occludentes which obliterate the intercellular space. These fusions occur usually at some distance below the free surface either independently or in continuity with a second intercellular junction, the zonula adhaerens. The luminal junction is usually formed by a zonula adhaerens or, occasionally, by a zonula occludens. The finely granular and filamentous cytoplasm contains supranuclear dense bodies, some of which are probably lysosomes and dense whorls of perinuclear filaments which send fascicles toward the lateral plasmalemma. The apical regions of the cytoplasm contain the basal body complexes of neighboring cilia. These complexes include a striated basal foot and short, non-striated rootlets emanating from the wall of each basal body. The rootlets end in a zone of granules about the proximal region of the basal body, adjacent to which may lie a striated mass of variable shape. All components of the basal body complex of adjacent cilia are independent of each other.

scholarly journals THE RELATIONSHIP BETWEEN THE FINE STRUCTURE AND DIRECTION OF BEAT IN GILL CILIA OF A LAMELLIBRANCH MOLLUSC

1961 ◽  
Vol 11 (1) ◽  
pp. 179-205 ◽  
Author(s):  
I. R. Gibbons
Keyword(s):  
Fine Structure ◽  
Cell Surface ◽  
Basal Body ◽  
Transitional Region ◽  
Basal Bodies ◽  
Conical Structure ◽  
The Relationship ◽  
Basal Foot ◽  
Different Levels ◽  
Outer Fiber

This paper describes the fine structure and its relationship to the direction of beat in four types of cilia on the gill of the fresh-water mussel Anodonta cataracta. The cilia contain nine outer, nine secondary, and two central fibers, such as have been described previously in other material. Each outer fiber is a doublet with one subfiber bearing arms. One particular pair of outer fibers (numbers 5 and 6) are joined together by a bridge. The two central fibers are enclosed by a central sheath; also present in this region is a single, small mid-fiber. The different groups of fibers are connected together by radial links that extend from the outer to the secondary fibers, and from the secondary fibers to the central sheath. The basal body consists of a cylinder of nine triplet fibers. Projecting from it on one side is a dense conical structure called the basal foot. The cylinder of outer fibers continues from the basal body into the cilium, passing through a complex transitional region in which five distinct changes of structure occur at different levels. There are two sets of fibers associated with the basal bodies: a pair of striated rootlets that extends from each basal body down into the cell, and a system of fine tubular fibers that runs parallel to the cell surface. The relationship between fine structure and direction of beat is the same in all four types of cilia examined. The plane of beat is perpendicular to the plane of the central fibers, with the effective stroke toward the bridge between outer fibers 5 and 6, and toward the foot on the basal body.

The fine structure of zoospores of Harpochytrium hedinii

1980 ◽  
Vol 58 (19) ◽  
pp. 2090-2097 ◽  
Author(s):  
Larry P. Gauriloff ◽  
Rona J. Delay ◽  
Melvin S. Fuller
Keyword(s):  
Fine Structure ◽  
Basal Body ◽  
Posterior Region ◽  
Anterior Region ◽  
Serial Sections ◽  
Wide System ◽  
Body Complex

The fine structure of the Harpochytrium hedinii Wille zoospore is reexamined using serial sections. All of the major organelles are located in the posterior two-thirds of the zoospore; the anterior region contains only a few vacuoles and a network of filaments. The basal body complex is located at the center of the posterior end of the zoospore. The nucleus and "nuclear cap" are located directly anterior to the basal body complex on one side of the zoospore. All of the microbodies, lipid globules, and mitochondria are arranged into a complex associated with the rumposome along the opposite side of the zoospore. A spore-wide system of cisternae, the vesicular system, is continuous throughout the posterior region of the zoospore. The overall arrangement of organelles in the H. hedinii zoospore most closely resembles the internal morphologies of certain chytridialean zoospores. This suggests that Harpochytrium may be more closely related to the chytrids than has been previously assumed.

Ultrastructure of the basal body apparatus in epidermal cells of a sponge larva (Aplysilla SP: Demospongiae)

1992 ◽  
Vol 50 (1) ◽  
pp. 928-929
Author(s):  
R.L. Pinto ◽  
R.M. Woollacott
Keyword(s):  
Sodium Bicarbonate ◽  
Epoxy Resin ◽  
Basal Body ◽  
Phosphate Buffer ◽  
Similar Data ◽  
Basal Apparatus ◽  
Striated Rootlet ◽  
The Common ◽  
Basal Foot ◽  
Sexually Mature

The basal body and its associated rootlet are the organelles responsible for anchoring the flagellum or cilium in the cytoplasm. Structurally, the common denominators of the basal apparatus are the basal body, a basal foot from which microtubules or microfilaments emanate, and a striated rootlet. A study of the basal apparatus from cells of the epidermis of a sponge larva was initiated to provide a comparison with similar data on adult sponges.Sexually mature colonies of Aplysillasp were collected from Keehi Lagoon Marina, Honolulu, Hawaii. Larvae were fixed in 2.5% glutaraldehyde and 0.14 M NaCl in 0.2 M Millonig’s phosphate buffer (pH 7.4). Specimens were postfixed in 1% OsO4 in 1.25% sodium bicarbonate (pH 7.2) and embedded in epoxy resin. The larva ofAplysilla sp was previously described (as Dendrilla cactus) based on live observations and SEM by Woollacott and Hadfield.

Fine structure of the rectal papillae of the oriental fruuit fly, Dacus dorsalis Hendel (Tephritidae, Diptera Insecta)

1990 ◽  
Vol 48 (3) ◽  
pp. 498-499
Author(s):  
Len Wen-Yung ◽  
Mei-Jung Lin
Keyword(s):  
Fine Structure ◽  
Cell Membrane ◽  
Intercellular Space ◽  
Anterior Part ◽  
Apical Cell ◽  
Posterior Part ◽  
Apical Cell Membrane ◽  
Dacus Dorsalis ◽  
Radial Cell ◽  
Circular Base

Four cone-shaped rectal papillae locate at the anterior part of the rectum in Dacus dorsalis fly. The circular base of the papilla protrudes into the haemolymph (Fig. 1,2) and the rest cone-shaped tip (Fig. 2) inserts in the rectal lumen. The base is surrounded with the cuticle (Fig. 5). The internal structure of the rectal papilla (Fig. 3) comprises of the cortex with the columnar epithelial cells and a rod-shaped medulla. Between them, there is the infundibular space and many trabeculae connect each other. Several tracheae insert into the papilla through the top of the medulla, then run into the cortical epithelium and locate in the intercellular space. The intercellular sinuses distribute in the posterior part of the rectal papilla.The cortex of the base divides into about thirty segments. Between segments there is a radial cell (Fig. 4). Under the cuticle, the apical cell membrane of the cortical epithelium is folded into a regular border of leaflets (Fig. 5).

scholarly journals Fine structure of the brain in Amphinomida (Annelida)

2021 ◽  
Author(s):  
Patrick Beckers ◽  
Ekin Tilic
Keyword(s):  
Fine Structure ◽  
The Brain

scholarly journals Product innovation design and its method: From the perspective of embodiment cognition

2021 ◽  
Vol 236 ◽  
pp. 04057
Author(s):  
Shengfang Peng ◽  
Baoying Peng ◽  
Xiaoxuan Li
Keyword(s):  
Cognitive Psychology ◽  
Embodied Cognition ◽  
Human Body ◽  
Product Innovation ◽  
Natural Interaction ◽  
New Approach ◽  
The Subject ◽  
Body Complex ◽  
The Mind ◽  
The Brain

In recent years, embodied cognition has become a new approach in the field of cognitive psychology. The shift in cognitive psychology from a focus on the brain to a focus on the human body，just as from the disembodied cognition to the embodied cognition is valuable for many fields related to cognitive science including product design and its method. With Gibson’s theory of affordances, embodied cognition is a perfect explanation of today’s products guided by the idea of intuitive design and its logic. On the premise of embodied cognition, it is the “Mind-Body complex” that serves as the subject of behavior and interaction, the basis of “natural interaction” in Intelligent age, and the foundation for building a more complete theory of “user experience”. Based on the embodied cognitive, the method of design and its research should put more emphasis on specific tools.

Comparative study of axopodial microtubule patterns and possible mechanisms of pattern control in the centrohelidian heliozoa Acanthocystis, Raphidiophrys and Heterophrys

1977 ◽  
Vol 25 (1) ◽  
pp. 205-232
Author(s):  
C.F. Bardele
Keyword(s):  
Fine Structure ◽  
Conformational Changes ◽  
Basal Body ◽  
Basic Unit ◽  
Lateral Growth ◽  
Secondary Nucleation ◽  
Body Formation ◽  
Pattern Control ◽  
Nucleation Sites ◽  
Equilateral Triangles

The axopodial microtubule pattern of 9 centrohelidians belonging to the genera Acanthocystis, Raphidiophrys and Heterophrys, as well as the fine structure of their microtubule organizing centre, the centroplast, was studied to determine the rules which govern their patterns. Microtubules capable of binding a xamimum of 4 linkers are arranged in regularly distorted hexagons and equilateral triangles. The number of microtubules present in each axoneme ranges from some 140 in Acanthocystis turfacea to as few as 6 in Heterophrys marina (Stock I). In the later species each axoneme contains a single hexagon of microtubules only. In other Heterophrys species, the central hexagon is surrounded by closely packed microtubules or by microtubules arranged in pentagons; only the central hexagon is anchored in the centroplast shell, whereas additional microtubules seem to originate from secondary nucleation sites somewhat distal to the centroplast. It is argued that the distortion of the basic unit hexagon (with alternate angles close to 134 degrees and 106 degrees) indicates that the microtubules are composed of 13 protofilaments. While in the larger Acanthocystis and Raphidiophrys species, the pattern may result from self-linkage, the arrays found in the Heterophrys species seem to favour a template-determined linkage. To explain the formation of the central hexagon in Heterophrys and balanced lateral growth in the larger microtubule arrays, a ‘linker-nucleation hypothesis’ is proposed. The assumption is made that graded conformational changes in the microtubule subunits not only specify the position where the next linker will bind, but that this linker, through linkage, becomes able to induce secondary microtubule nucleation, which will result in balanced lateral growth of the array. The application of this hypothesis to other microtubule systems, e.g. basal body formation, is discussed.

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