Cell Wall Perforation in Laticifers of Papaver somniferum L.

1977 ◽  
Vol 138 (4) ◽  
pp. 402-408 ◽  
Author(s):  
Craig L. Nessler ◽  
Paul G. Mahlberg
PERENNIAL ◽  
2019 ◽  
Vol 15 (1) ◽  
Author(s):  
Nurul Muhlisah Mompewa ◽  
Andi Detti Yunianti ◽  
Siti Halimah Larekeng

Characteristics of anatomy structure cell walls can be used as a reference to determine the quality of wood, especially in the final product. Variability anatomy of wood is varies greatly between species, parts of the stem and place of growth and provenance. For the purpose of the study, teak wood samples from Wajo provenance. This study aims to identify the structure anatomy characteristics cell wall of jabon merah from Wajo provenance. The structure anatomy cell wall observed were a microfibril angle (MFA), a pit in cell wall, perforation plate, and tylosis. Results showed that the structure anatomy cell wall characteristics jabon merah from Wajo provenance had a MFA values of 22.21°,intervessel pits polygonal alternating, scalariform perforation plates, and have a tylosis in the vessel.


1982 ◽  
Vol 60 (12) ◽  
pp. 2882-2888 ◽  
Author(s):  
Evelyne Westphal

Leaf epidermis cells of Solanum dulcamara cultured for several hours show, after cell wall perforation by Eriophyes cladophthirus, an increase of the vacuolar pH (≥8) both in susceptible and resistant plants. This reaction is more rapid on susceptible plants and the injured cell remains alive. In contrast, on resistant plants, the reaction starts later and the injured cell collapses and dies.


2015 ◽  
Vol 5 (2/3) ◽  
pp. 86 ◽  
Author(s):  
Ran Ran Geng ◽  
Zhi Yuan Yao ◽  
James K. Mills
Keyword(s):  

2004 ◽  
Vol 233 (1) ◽  
pp. 131-138 ◽  
Author(s):  
Emmanuelle Palumbo ◽  
Christine F. Favier ◽  
Marie Deghorain ◽  
Pier Sandro Cocconcelli ◽  
Corinne Grangette ◽  
...  

1979 ◽  
Vol 57 (6) ◽  
pp. 675-685 ◽  
Author(s):  
Craig L. Nessler ◽  
Paul G. Mahlberg

Callus was initiated from seedling hypocotyls and mature stems of Papaver somniferum and maintained in culture. The ultrastructure of callus cells resembled parenchyma of intact plants, their most conspicuous feature being a large central vacuole. Meristemoids were formed at random on the surface of calli transferred to the appropriate medium. In cross section, meristemoids appeared as an inner meristematic region surrounded by several layers of concentrically arranged cells. Cells of meristemoids were smaller, more densely cytoplasmic, and more compactly arranged compared with callus. Roots and shoots induced to form from callus possessed cells that were morphologically and developmentally similar to laticifers in intact plants. Laticifers in redifferentiated organs, like those in intact plants, contained numerous capped vesicles that are apparently derived from stacked endoplasmic reticulum. Cell wall perforations between adjacent laticifer elements in redifferentiated organs developed by the gradual, simultaneous thinning of walls at the perforation sites.


1997 ◽  
Vol 161 ◽  
pp. 491-504 ◽  
Author(s):  
Frances Westall

AbstractThe oldest cell-like structures on Earth are preserved in silicified lagoonal, shallow sea or hydrothermal sediments, such as some Archean formations in Western Australia and South Africa. Previous studies concentrated on the search for organic fossils in Archean rocks. Observations of silicified bacteria (as silica minerals) are scarce for both the Precambrian and the Phanerozoic, but reports of mineral bacteria finds, in general, are increasing. The problems associated with the identification of authentic fossil bacteria and, if possible, closer identification of bacteria type can, in part, be overcome by experimental fossilisation studies. These have shown that not all bacteria fossilise in the same way and, indeed, some seem to be very resistent to fossilisation. This paper deals with a transmission electron microscope investigation of the silicification of four species of bacteria commonly found in the environment. The Gram positiveBacillus laterosporusand its spore produced a robust, durable crust upon silicification, whereas the Gram negativePseudomonas fluorescens, Ps. vesicularis, andPs. acidovoranspresented delicately preserved walls. The greater amount of peptidoglycan, containing abundant metal cation binding sites, in the cell wall of the Gram positive bacterium, probably accounts for the difference in the mode of fossilisation. The Gram positive bacteria are, therefore, probably most likely to be preserved in the terrestrial and extraterrestrial rock record.


Author(s):  
D. James Morré ◽  
Charles E. Bracker ◽  
William J. VanDerWoude

Calcium ions in the concentration range 5-100 mM inhibit auxin-induced cell elongation and wall extensibility of plant stems. Inhibition of wall extensibility requires that the tissue be living; growth inhibition cannot be explained on the basis of cross-linking of carboxyl groups of cell wall uronides by calcium ions. In this study, ultrastructural evidence was sought for an interaction of calcium ions with some component other than the wall at the cell surface of soybean (Glycine max (L.) Merr.) hypocotyls.


Author(s):  
L. V. Leak

Electron microscopic observations of freeze-fracture replicas of Anabaena cells obtained by the procedures described by Bullivant and Ames (J. Cell Biol., 1966) indicate that the frozen cells are fractured in many different planes. This fracturing or cleaving along various planes allows one to gain a three dimensional relation of the cellular components as a result of such a manipulation. When replicas that are obtained by the freeze-fracture method are observed in the electron microscope, cross fractures of the cell wall and membranes that comprise the photosynthetic lamellae are apparent as demonstrated in Figures 1 & 2.A large portion of the Anabaena cell is composed of undulating layers of cytoplasm that are bounded by unit membranes that comprise the photosynthetic membranes. The adjoining layers of cytoplasm are closely apposed to each other to form the photosynthetic lamellae. Occassionally the adjacent layers of cytoplasm are separated by an interspace that may vary in widths of up to several 100 mu to form intralamellar vesicles.


Author(s):  
Manfred E. Bayer

Bacterial viruses adsorb specifically to receptors on the host cell surface. Although the chemical composition of some of the cell wall receptors for bacteriophages of the T-series has been described and the number of receptor sites has been estimated to be 150 to 300 per E. coli cell, the localization of the sites on the bacterial wall has been unknown.When logarithmically growing cells of E. coli are transferred into a medium containing 20% sucrose, the cells plasmolize: the protoplast shrinks and becomes separated from the somewhat rigid cell wall. When these cells are fixed in 8% Formaldehyde, post-fixed in OsO4/uranyl acetate, embedded in Vestopal W, then cut in an ultramicrotome and observed with the electron microscope, the separation of protoplast and wall becomes clearly visible, (Fig. 1, 2). At a number of locations however, the protoplasmic membrane adheres to the wall even under the considerable pull of the shrinking protoplast. Thus numerous connecting bridges are maintained between protoplast and cell wall. Estimations of the total number of such wall/membrane associations yield a number of about 300 per cell.


Author(s):  
B.K. Ghosh

Periplasm of bacteria is the space outside the permeability barrier of plasma membrane but enclosed by the cell wall. The contents of this special milieu exterior could be regulated by the plasma membrane from the internal, and by the cell wall from the external environment of the cell. Unlike the gram-negative organism, the presence of this space in gram-positive bacteria is still controversial because it cannot be clearly demonstrated. We have shown the importance of some periplasmic bodies in the secretion of penicillinase from Bacillus licheniformis.In negatively stained specimens prepared by a modified technique (Figs. 1 and 2), periplasmic space (PS) contained two kinds of structures: (i) fibrils (F, 100 Å) running perpendicular to the cell wall from the protoplast and (ii) an array of vesicles of various sizes (V), which seem to have evaginated from the protoplast.


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