scholarly journals Vascular Transfer Cells in the Wheat Spikelet

1971 ◽  
Vol 24 (1) ◽  
pp. 35 ◽  
Author(s):  
S-Y Zee ◽  
TP O'brien
Keyword(s):  
Transfer Cells ◽  
Solute Transfer ◽  
Vascular Tissues ◽  
Lanthanum Tracer ◽  
Colloidal Lanthanum

Xylem and phloem transfer cells are present at the nodal regions where the sterile glumes, lemma, palea, and caryopsis are attached to the rachis and rachilla. The course and distribution of the vascular tissues and the structure of the transfer cells are described. Experiments with colloidal lanthanum tracer fed via the trans-piration stream have indicated that the walls of the transfer cells are relatively porous. The possibility that the transfer cells play an important role in the regula-tion of solute transfer to the developing grain is discussed.

scholarly journals The Occurrence of Transfer Cells in the Vascular Tissues of the Coleoptilar Node of Wheat

1970 ◽  
Vol 23 (3) ◽  
pp. 709 ◽  
Author(s):  
TP O'brien ◽  
S Zee ◽  
JG Swift
Keyword(s):  
Short Distance ◽  
Vascular Tissue ◽  
Embryo Sac ◽  
Transfer Cells ◽  
Large Sample ◽  
Vascular Tissues ◽  
Wall Ingrowths ◽  
Distance Transport

Wooding and Northcote (1965), Gunning, Pate, and Briarty (1968), Gunning and Pate (1969), and Pate and Gunning (1969) have drawn attention recently to the presence of cells with wall ingrowths in a number of sites in plants at which one might expect short-distance transport of considerable quantities of solutes. Gunning and Pate (1969) suggested that these cells be called "transfer cells" and surveyed their distribution in the leaves of a large sample of Angiosperms. These cells have not been found in the leaves of any grasses, and they have been demonstrated in the Gramineae only in the embryo sac of maize (Diboll 1968). In this paper, transfer cells are illustrated in the vascular tissue at the coleoptilar node in wheat, and the possible functions of these cells at this site are discussed.

Aspects of Vascular Anatomy and Differentiation of Vascular Tissues and Transfer Cells in Vegetative Nodes of Wheat

1979 ◽  
Vol 27 (6) ◽  
pp. 703 ◽  
Author(s):  
CH Busby ◽  
TP O'Brien
Keyword(s):  
Shoot Apex ◽  
Vascular Anatomy ◽  
Transfer Cells ◽  
Mature Leaf ◽  
Tracheary Elements ◽  
Vascular Tissues ◽  
Wall Ingrowth ◽  
Mature Node

Xylem transfer cells are strongly developed in the departing leaf traces of the mature wheat node. Their differentiation is initiated soon after the appearance of the first tracheary elements in these bundles. and wall ingrowth development reaches its peak just as the leaf to which the bundle belongs becomes fully expanded. It is suggested that the xylem transfer cells play an important role in redirecting solutes travelling in the xylem of the mature leaf to the developing leaves at the shoot apex. It is further suggested that they form an integral part of the normal xylem transpiration pathway, compensating for xylem restrictions and discontinuities in the mature node. Phloem transfer cells also appear very early in the differentiation of the nodal vasculature, although their function remains obscure.

Ultrastructure of melanocyte-keratinocyte interactions and pigment transfer in vitro

1978 ◽  
Vol 36 (2) ◽  
pp. 650-651
Author(s):  
Raul I. Garcia ◽  
Evelyn A. Flynn ◽  
George Szabo
Keyword(s):  
Direct Injection ◽  
Skin Pigmentation ◽  
Freeze Fracture ◽  
Pigment Granule ◽  
Time Lapse ◽  
Ultrastructural Level ◽  
Lanthanum Tracer ◽  
A Cell

Skin pigmentation in mammals involves the interaction of epidermal melanocytes and keratinocytes in the structural and functional unit known as the Epidermal Melanin Unit. Melanocytes(M) synthesize melanin within specialized membrane-bound organelles, the melanosome or pigment granule. These are subsequently transferred by way of M dendrites to keratinocytes(K) by a mechanism still to be clearly defined. Three different, though not necessarily mutually exclusive, mechanisms of melanosome transfer have been proposed: cytophagocytosis by K of M dendrite tips containing melanosomes, direct injection of melanosomes into the K cytoplasm through a cell-to-cell pore or communicating channel formed by localized fusion of M and K cell membranes, release of melanosomes into the extracellular space(ECS) by exocytosis followed by K uptake using conventional phagocytosis. Variability in methods of transfer has been noted both in vivo and in vitro and there is evidence in support of each transfer mechanism. We Have previously studied M-K interactions in vitro using time-lapse cinemicrography and in vivo at the ultrastructural level using lanthanum tracer and freeze-fracture.

Anatomy and ultrastructure of haustoria in selected West Australian parasitic angiosperms

1990 ◽  
Vol 48 (3) ◽  
pp. 690-691
Author(s):  
John Kuo ◽  
John S. Pate
Keyword(s):  
Parasitic Plants ◽  
The Other ◽  
Nutrient Transfer ◽  
Direct Solution ◽  
Tracheary Elements ◽  
Solute Transfer ◽  
Glycol Methacrylate ◽  
Australian Species ◽  
Anatomy And Ultrastructure ◽  
Solution Transfer

Our understanding of nutrient transfer between host and flowering parasitic plants is usually based mainly on physiological concepts, with little information on haustorial structure related to function. The aim of this paper is to study the haustorial interface and possible pathways of water and solute transfer between a number of host and parasites.Haustorial tissues were fixed in glutaraldehyde and embedded in glycol methacrylate (LM), or fixed in glutaraldehyde then OsO4 and embedded in Spurr’s resin (TEM).Our study shows that lumen to lumen continuity occurs between tracheary elements of a host and four S.W. Australian species of aerial mistletoes (Fig. 1), and some root hemiparasites (Exocarpos spp. and Anthobolus foveolatus) (Fig. 2). On the other hand, haustorial interfaces of the root hemiparasites Olax phyllanthi and Santalum (2 species) are comprised mainly of parenchyma, as opposed to terminating tracheads or vessels, implying that direct solution transfer between partners via vessels or tracheary elements may be limited (Fig. 3).

Fibroblast Growth Factor 23 Expression in Human Calcified Vascular Tissues

2019 ◽  
Author(s):  
Javier Donate-Correa ◽  
Ernesto Martín-Núñez ◽  
Carolina Hernández-Carballo ◽  
Carla Ferri ◽  
Víctor G. Tagua ◽  
...  
Keyword(s):  
Growth Factor ◽  
Fibroblast Growth Factor ◽  
Fibroblast Growth Factor 23 ◽  
Fibroblast Growth ◽  
Vascular Tissues

Modelling of Solute Transfer to Surface Runoff

1992 ◽  
Vol 26 (7-8) ◽  
pp. 1851-1856 ◽  
Author(s):  
J. L. Lai ◽  
K. S. L. Lo
Keyword(s):  
Potassium Chloride ◽  
Surface Runoff ◽  
Laboratory Experiments ◽  
Overland Flow ◽  
Chloride Concentration ◽  
Runoff Water ◽  
Mixing Depth ◽  
Change Rate ◽  
Solute Transfer ◽  
The Media

A mixing-based model for describing solute transfer to overland flow was developed. This model included a time-dependent mixing depth of the top layer and a complete-mixed surface runoff zone. In a series of laboratory experiments, runoff was passed at various velocities and depths over a medium bed. The media were saturated with uniform concentration of potassium chloride solution. Runoff water was sampled at the beginning and end of the flume and the potassium chloride concentration analyzed. Using this model, dimensionless ultimate mixing depth and dimensionless change rate of mixing depth from experimental data were investigated and implemented. The results showed that the Reynolds number and relative roughness are two important factors.

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