scholarly journals Studies on the Comparative Physiology of Chara Australis II. The Fine Structure of The Protoplast

1964 ◽  
Vol 17 (2) ◽  
pp. 372 ◽  
Author(s):  
TC CHAMBERS ◽  
FV MERCER
Keyword(s):  
Fine Structure ◽  
Unit Volume ◽  
Higher Plants ◽  
Linear Phase ◽  
Comparative Physiology ◽  
Thin Sections ◽  
Golgi Bodies ◽  
Constant Structure ◽  
Parenchyma Cells ◽  
Chara Australis

The fine structure of the internodal cells of G. australis in the linear phase of cell expansion is described from electron micrographs of thin sections of osmium. and permanganate-fixed material. . The static picture obtained is basically similar to that of the parenchyma cells of higher plants as established by electron-microscope observations. A unit volume of protoplast has the same fine structure in cells ranging from 1 em to many centimetres in length, and contains cell wall, plasmalemma, tonoplast, endoplasmic reticulum, golgi bodies, micro somes, mitochondria, chloro_ plasts, nuclei, and other inclusions. This constant structure may account for the constant metabolism per unit volume of protoplast during the linear phase of development. A brief discussion of the possible significance of this picture of the structure of the internodal protoplast to the functional activity of the cell is given.

scholarly journals Studies on the, Comparative Physiology of Chara Australis 1. Growth Pattern and Gross Cytology of the Internodal Oell

1964 ◽  
Vol 17 (1) ◽  
pp. 49 ◽  
Author(s):  
Marie J Peebles FV Mercer ◽  
TC Chambers
Keyword(s):  
Growth Pattern ◽  
Unit Volume ◽  
Exponential Phase ◽  
Linear Phase ◽  
Comparative Physiology ◽  
Growth Phases ◽  
Internodal Cell ◽  
Chara Australis ◽  
Very High ◽  
In Cells

The growth of the internodal cell and its parts appears to be allometric. Two growth phases are recognized, an exponential phase in the young cells followed by a linear phase during which the internode expands by up to 200 mm in length. In the exponential phase the cytoplasm to vacuole ratio declines from a very high value to about 0�04--0�06 and then remains constant throughout the linear phase. In the linear phase the structure of the protoplast, at the light.microscope level, is similar for all cells; a unit volume of the protoplast appears similar in cells from 10 to 200 rum in length.

scholarly journals CHROMATOPHORE DEVELOPMENT, PITS, AND OTHER FINE STRUCTURE IN THE RED ALGA, LOMENTARIA BAILEYANA (HARV.) FARLOW

1962 ◽  
Vol 12 (3) ◽  
pp. 553-569 ◽  
Author(s):  
G. Benjamin Bouck
Keyword(s):  
Endoplasmic Reticulum ◽  
Plasma Membrane ◽  
Fine Structure ◽  
Higher Plants ◽  
Red Alga ◽  
Cellular Structures ◽  
Secretory Function ◽  
Thin Sections ◽  
Floridean Starch ◽  
Oriented Parallel

Thin sections of the red alga, Lomentaria baileyana, a tubular member of the Rhodymeniales, were examined after permanganate fixation and Araldite embedding. Many of the cellular structures in Lomentaria were found to be similar to analogous structures in animals and higher plants. However, in the walls between cells are modified areas generally known as pits which are unique to the higher orders of red algae (Florideae). In this study the pits were found to consist of a plug-like structure surrounded by an uninterrupted membrane apparently continuous with the plasma membrane. Examination of the chromatophore revealed a characteristic limiting membrane, a relatively sparse distribution of plates, no grana, and a single disc apparently oriented parallel to the limiting membrane. In addition to their origin from non-lamellate proplastids, chromatophores were found capable of division by simple constriction. Floridean starch grains were observed outside the chromatophore and the possibility of an association of the first formed grains with portions of the endoplasmic reticulum is considered. Gland cells seem to have a high proportion of Golgi components (dictyosomes), and are believed to have some kind of secretory function. Many of the Golgi vesicles seem to open on the wall and presumably discharge their contents.

Two- or three-way observations of the identical cell elements within the same sections by LM, TEM and/or SEM

1978 ◽  
Vol 36 (2) ◽  
pp. 82-83 ◽  
Author(s):  
Nakazo Watari ◽  
Yasuaki Hotta ◽  
Yoshio Mabuchi
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Fine Structure ◽  
Light Microscopy ◽  
Thin Sections ◽  
Transmission Electron ◽  
Identical Cell ◽  
Electron Microscopes ◽  
Scanning Electron

It is very useful if we can observe the identical cell elements within the same sections by light microscopy (LM), transmission electron microscopy (TEM) and/or scanning electron microscopy (SEM) sequentially, because, the cell fine structure can not be indicated by LM, while the color is; on the other hand, the cell fine structure can be very easily observed by EM, although its color properties may not. However, there is one problem in that LM requires thick sections of over 1 μm, while EM needs very thin sections of under 100 nm. Recently, we have developed a new method to observe the same cell elements within the same plastic sections using both light and transmission (conventional or high-voltage) electron microscopes.In this paper, we have developed two new observation methods for the identical cell elements within the same sections, both plastic-embedded and paraffin-embedded, using light microscopy, transmission electron microscopy and/or scanning electron microscopy (Fig. 1).

Fine Structure of Interdental Cells in the Mouse Cochlea

1970 ◽  
Vol 28 ◽  
pp. 140-141
Author(s):  
Roberta M. Bruck
Keyword(s):  
Fine Structure ◽  
Electron Microscope ◽  
Young Adult ◽  
Uranyl Acetate ◽  
Ground Substance ◽  
Tectorial Membrane ◽  
Lead Citrate ◽  
Unusual Structure ◽  
Thin Sections ◽  
Collagenous Fibers

An unusual structure in the cochlea is the spiral limbus; this periosteal tissue consists of stellate fibroblasts and collagenous fibers embedded in a translucent ground substance. The collagenous fibers are arranged in vertical columns (the auditory teeth of Haschke). Between the auditory teeth are interdental furrows in which the interdental cells are situated. These epithelial cells supposedly secrete the tectorial membrane.The fine structure of interdental cells in the rat was reported by Iurato (1962). Since the mouse appears to be different, a description of the fine structure of mouse interdental cells' is presented. Young adult C57BL/6J mice were perfused intervascularly with 1% paraformaldehyde/ 1.25% glutaraldehyde in .1M phosphate buffer (pH7.2-7.4). Intact cochlea were decalcified in .1M EDTA by the method of Baird (1967), postosmicated, dehydrated, and embedded in Araldite. Thin sections stained with uranyl acetate and lead citrate were examined in a Phillips EM-200 electron microscope.

Cell Fine Structure as Revealed in Dessicator-Dried Resinless Sections

1981 ◽  
Vol 39 ◽  
pp. 622-623
Author(s):  
R. P. Becker ◽  
J. J. Wolosewick ◽  
J. Ross-Stanton
Keyword(s):  
Fine Structure ◽  
Tannic Acid ◽  
Three Dimensional ◽  
Albino Rats ◽  
Cell Organelles ◽  
Vascular Perfusion ◽  
Thin Sections ◽  
Carbon Coated ◽  
Embedding Medium ◽  
Polyethylene Glycol 6000

Methodology has been introduced recently which allows transmission and scanning electron microscopy of cell fine structure in semi-thin sections unencumbered by an embedding medium. Images obtained from these “resinless” sections show a three-dimensional lattice of microtrabeculfee contiguous with cytoskeletal structures and membrane-bounded cell organelles. Visualization of these structures, especially of the matiiDra-nous components, can be facilitated by employing tannic acid in the fixation step and dessicator drying, as reported here.Albino rats were fixed by vascular perfusion with 2% glutaraldehyde or 1.5% depolymerized paraformaldehyde plus 2.5% glutaraldehyde in 0.1M sodium cacodylate (pH 7.4). Tissues were removed and minced in the fixative and stored overnight in fixative containing 4% tannic acid. The tissues were rinsed in buffer (0.2M cacodylate), exposed to 1% buffered osmium tetroxide, dehydrated in ethyl alcohol, and embedded in pure polyethylene glycol-6000 (PEG). Sections were cut on glass knives with a Sorvall MT-1 microtome and mounted onto poly-L-lysine, formvar-carbon coated grids while submerged in a solution of 95% ethanol containing 5% PEG.

scholarly journals FINE STRUCTURE OF LIPID-DEPLETED MITOCHONDRIA

1967 ◽  
Vol 32 (1) ◽  
pp. 193-208 ◽  
Author(s):  
Sidney Fleischer ◽  
Becca Fleischer ◽  
Walther Stoeckenius
Keyword(s):  
Fine Structure ◽  
Reductase Activity ◽  
Aqueous Acetone ◽  
Unit Membrane ◽  
Mitochondrial Membranes ◽  
Inner Membrane ◽  
Thin Sections ◽  
Membrane Particles ◽  
Succinate Cytochrome C Reductase ◽  
Many Particles

The fine structure of mitochondria and submitochondrial vesicles depleted of their lipid by extraction with aqueous acetone was studied. Thin sections of mitochondrial membranes depleted of more than 95% of their lipid retained the unit membrane structure. Densitometer tracings of the electron micrographs showed that the unit membrane of extracted mitochondria was, on the average, wider than that of unextracted controls and showed a greater variation in width. The outer membrane was lost in mitochondria from which 80–95% of the lipids was extracted. Inner membrane particles were present on submitochondrial vesicles depleted of up to 85% of their lipids. However, when more than 95% of the lipid was removed, few, if any, particles remained attached to the membranes but many particles were found unattached in the background. When lipid was restored to lipid-deficient preparations, the mitochondrial membranes were found to be devoid of inner membrane particles but were fully active with respect to succinate-cytochrome c reductase activity.

scholarly journals STUDIES ON THE MODE OF ACTION OF EXCESS OF VITAMIN A

1963 ◽  
Vol 17 (1) ◽  
pp. 111-121 ◽  
Author(s):  
Audrey M. Glauert ◽  
Mary R. Daniel ◽  
J. A. Lucy ◽  
J. T. Dingle
Keyword(s):  
Electron Microscopy ◽  
Fine Structure ◽  
Vitamin A ◽  
Phase Contrast ◽  
Phase Contrast Microscopy ◽  
Intact Cells ◽  
Thin Sections ◽  
Initial Effect ◽  
Contrast Microscopy ◽  
Site Of Action

Rabbit erythrocytes have been haemolysed by treatment with vitamin A alcohol and the sequence of changes in the fine structure of the cells during lysis has been investigated by phase contrast microscopy of intact cells and electron microscopy of thin sections. The initial effect of the vitamin, which occurs within 1 minute, is the production of cells of bizarre appearance which have a greatly increased surface area relative to untreated cells. Large indentations appear in the surfaces of the cells, and vacuoles are formed from the indentations by a process that resembles micropinocytosis. The cells then become spherical and loss of haemoglobin begins as breaks appear in the membranes of some cells; finally, ghosts are produced that are no longer spherical but still contain numerous vacuoles. These observations support the thesis that one site of action of vitamin A is at lipoprotein membranes.

scholarly journals Three-dimensional electron microscopy of ribosomal chromatin in two higher plants: a cytochemical, immunocytochemical, and in situ hybridization approach.

1991 ◽  
Vol 39 (11) ◽  
pp. 1495-1506 ◽  
Author(s):  
P M Motte ◽  
R Loppes ◽  
M Menager ◽  
R Deltour
Keyword(s):  
Electron Microscopy ◽  
In Situ Hybridization ◽  
Spatial Organization ◽  
Higher Plants ◽  
Three Dimensional ◽  
Spatial Arrangement ◽  
Thin Sections ◽  
Cytoplasmic Dna ◽  
Immunocytochemical Techniques

We report the 3-D arrangement of DNA within the nucleolar subcomponents from two evolutionary distant higher plants, Zea mays and Sinapis alba. These species are particularly convenient to study the spatial organization of plant intranucleolar DNA, since their nucleoli have been previously reconstructed in 3-D from serial ultra-thin sections. We used the osmium ammine-B complex (a specific DNA stain) on thick sections of Lowicryl-embedded root fragments. Immunocytochemical techniques using anti-DNA antibodies and rDNA/rDNA in situ hybridization were also applied on ultra-thin sections. We showed on tilted images that the OA-B stains DNA throughout the whole thickness of the section. In addition, very low quantities of cytoplasmic DNA were stained by this complex, which is now the best DNA stain used in electron microscopy. Within the nucleoli the DNA was localized in the fibrillar centers, where large clumps of dense chromatin were also visible. In the two plant species intranucleolar chromatin forms a complex network with strands partially linked to chromosomal nucleolar-organizing regions identified by in situ hybridization. This study describes for the first time the spatial arrangement of the intranucleolar chromatin in nucleoli of higher plants using high-resolution techniques.

scholarly journals Genetic fine-structure of the GA-1 locus in the higher plant Arabidopsis thaliana (L.) Heynh

1983 ◽  
Vol 41 (1) ◽  
pp. 57-68 ◽  
Author(s):  
M. Koornneef ◽  
J. Van Eden ◽  
C. J. Hanhart ◽  
A. M. M. De Jongh
Keyword(s):  
Arabidopsis Thaliana ◽  
Fine Structure ◽  
Higher Plants ◽  
Wild Type ◽  
Higher Plant ◽  
Selfed Progeny ◽  
Intragenic Deletion ◽  
Genetic Length ◽  
Genetic Fine Structure ◽  
Half Diallel

SUMMARYNon-germinating gibberellin (GA) responsive mutants are a powerful tool to study genetic fine structure in higher plants. Nine alleles (EMS-and fast neutron-induced) of the ga-1 locus of Arabidopsis thaliana were tested in a complete half-diallel. No wild type ‘recombinants’ were found in the selfed progeny of 9 homoallelic combinations (in total 3 × 105 plants); in the progenies from the 36 selfed hetero allelics the wild type frequency ranged from zero to 6·6 × 10−4. These frequencies allowed the construction of an internally consistent map for five different sites representing eight alleles. The ninth allele covered three sites and thus behaved like an intragenic deletion. The estimate of the total genetic length of the ga-1 locus was 0·07 cM. The order of the sites was also clearly reflected by the association with proximal outside markers. On the assumption that wild type gametes predominantly arise from reciprocal events, it was shown that a cross-over within the ga-1 locus leads to positive interference in the adjacent region.The results are discussed with respect to the mutagen used, the frequencies found in other plant and Drosophila genes, and the possible occurrence of gene conversion.

Association of malva vein-clearing virus and rhabdoviruslike particles with mottle and vein clearing of malva plants

1986 ◽  
Vol 64 (1) ◽  
pp. 85-89 ◽  
Author(s):  
Maria-Ivone C. Henriques ◽  
Fernando S. Henriques
Keyword(s):  
Inclusion Bodies ◽  
Inner Core ◽  
Dense Body ◽  
Mesophyll Cells ◽  
Cytoplasmic Inclusions ◽  
Thin Sections ◽  
Phloem Parenchyma ◽  
Vein Clearing ◽  
Perinuclear Space ◽  
Parenchyma Cells

Thin sections of malva (Malva sp.) leaves collected in the field and showing mottle and vein-clearing symptoms were examined by electron microscopy. Cytoplasmic inclusions typical of potyvirus and consisting of pinwheels, laminated aggregates, and scrolls were readily observed. In addition, rhabdoviruslike particles were also seen in the perinuclear space of phloem parenchyma cells and within membranous sacs scattered throughout the cytoplasm of other vascular bundle cells. Occasionally rhabdoparticles could be found embedded in an amorphous electron-dense body located within the cell vacuole. The rhabdovirus particles, approximately 75 × 300 nm, were bound by a membrane with outer projections and had an inner core displaying cross striations. The cytoplasm of infected mesophyll cells had chloroplasts containing large amorphous inclusion bodies and had extensive membranous tubules that were frequently associated with the potyvirus inclusions. These ultrastructural aspects, the size of the particles, and the data on host range indicate that malva plants under study were doubly infected by viruses which were tentatively identified as malva vein-clearing virus and a previously undescribed rhabdovirus.

Sign in / Sign up

Export Citation Format

Share Document