scholarly journals The Structure of the Cuticular Wax of Prune Plums and its Influence as a Water Barrier

1967 ◽  
Vol 20 (5) ◽  
pp. 895 ◽  
Author(s):  
Joan M Bain ◽  
D Mcg Mcbean

Wax on the surface of prune plums, sampled from 2 weeks before fruit was mature until 2 weeks after, was shown by electron microscopy, using the carbon� replica technique, to occur in a two-layer structure. The iruier layer consisted of a matrix of thin platelets, while the outer layer was composed of fragile projections, many of which appeared tubular. The incidence and complexity of the projections in the outer layer increased as the fruit matured.

1963 ◽  
Vol 16 (4) ◽  
pp. 818 ◽  
Author(s):  
TC Chambers ◽  
JV Possingham

The surface waxy bloom of sultana grapes has been studied using the carbon. replica technique in combination with electron microscopy. This layer consists of a series of overlapping wax platelets, each of which is about 0�1 f' wide. The air spaces between the wax platelets become filled with liquid when sultana berries are dipped in commercial emulsions known to accelerate their drying rate. Washing in distilled water removes this layer of dipping emulsion from the surface. The appearance of dipped and washed grapes is similar to that of untreated grapes.


1969 ◽  
Vol 22 (1) ◽  
pp. 101 ◽  
Author(s):  
Joan M Bain ◽  
D Mcg Mcbean

The development of the wax layer or bloom has been observed on prune plums throughout the growing season (177 days), using the carbon replica and thin�sectioning techniques of electron microscopy. Changes in their average fresh weight, surface area, percentage of total and soluble solids, and the amount of wax per fruit and per square centimetre were determined also at 12 intervals during their growth.


Author(s):  
Robert M. Glaeser ◽  
Thea B. Scott

The carbon-replica technique can be used to obtain information about cell-surface structure that cannot ordinarily be obtained by thin-section techniques. Mammalian erythrocytes have been studied by the replica technique and they appear to be characterized by a pebbly or “plaqued“ surface texture. The characteristic “particle” diameter is about 200 Å to 400 Å. We have now extended our observations on cell-surface structure to chicken and frog erythrocytes, which possess a broad range of cellular functions, and to normal rat lymphocytes and mouse ascites tumor cells, which are capable of cell division. In these experiments fresh cells were washed in Eagle's Minimum Essential Medium Salt Solution (for suspension cultures) and one volume of a 10% cell suspension was added to one volume of 2% OsO4 or 5% gluteraldehyde in 0.067 M phosphate buffer, pH 7.3. Carbon replicas were obtained by a technique similar to that employed by Glaeser et al. Figure 1 shows an electron micrograph of a carbon replica made from a chicken erythrocyte, and Figure 2 shows an enlarged portion of the same cell.


Author(s):  
C. N. Gordon

Gordon and Kleinschmidt have described a new preparative technique for visualizing DNA by electron microscopy. This procedure, which is a modification of Hall's “mica substrate technique”, consists of the following steps: (a) K+ ions on the cleavage surface of native mica are exchanged for Al3+ ions by ion exchange. (b) The mica, with Al3+ in the exchange sites on the surface, is placed in a dilute aqueous salt solution of DNA for several minutes; during this period DNA becomes adsorbed on the surface. (c) The mica with adsorbed DNA is removed from the DNA solution, rinsed, dried and visualized for transmission electron microscopy by Hall's platinum pre-shadow replica technique.In previous studies of circular DNA by this technique, most of the molecules seen were either broken to linears or extensively tangled; in general, it was not possible to obtain suitably large samples of open extended molecules for contour length measurements.


1956 ◽  
Vol 2 (4) ◽  
pp. 445-448 ◽  
Author(s):  
Marie H. Greider ◽  
Wencel J. Kostir ◽  
Walter J. Frajola

An electron microscope study of the nuclear membrane of Amoeba proteus by thin sectioning techniques has revealed an ultrastructure in the outer layer of the membrane that is homologous to the pores and annuli observed in the nuclear membranes of many other cell types studied by these techniques. An inner honeycombed layer apparently unique to Amoeba proteus is also described.


IAWA Journal ◽  
2005 ◽  
Vol 26 (2) ◽  
pp. 161-174 ◽  
Author(s):  
Hisashi Abe ◽  
Ryo Funada

We examined the orientation of cellulose microfibrils (Mfs) in the cell walls of tracheids in some conifer species by field emission-scanning electron microscopy (FE-SEM) and developed a model on the basis of our observations. Mfs depositing on the primary walls in differentiating tracheids were not well-ordered. The predominant orientation of the Mfs changed from longitudinal to transverse, as the differentiation of tracheids proceeded. The first Mfs to be deposited in the outer layer of the secondary wall (S1 layer) were arranged as an S-helix. Then the orientation of Mfs changed gradually, with rotation in the clockwise direction as viewed from the lumen side of tracheids, from the outermost to the innermost S1 layer. Mfs in the middle layer of the secondary wall (S2 layer) were oriented in a steep Z-helix with a deviation of less than 15° within the layer. The orientation of Mfs in the inner layer of the secondary wall (S3 layer) changed, with rotation in a counterclockwise direction as viewed from the lumen side, from the outermost to the innermost S3 layer. The angle of orientation of Mfs that were deposited on the innermost S3 layer varied among tracheids from 40° in a Z-helix to 20° in an S-helix.


Development ◽  
1984 ◽  
Vol 80 (1) ◽  
pp. 321-330
Author(s):  
Jonathan M. W. Slack

The development of ectoderm isolated from the animal pole of axolotl gastrulae is monitored by light microscopy, electron microscopy and analysis of newly synthesized proteins, glycoproteins and glycolipids. When control embryos are undergoing neurulation it is shown that the explants autonomously begin to express epidermal markers and do not express mesodermal markers. However the results suggest that not all the cells become epidermal and electron microscope examination shows that only the outer layer does so, the inner cells remaining undifferentiated.


1959 ◽  
Vol 37 (5) ◽  
pp. 633-637 ◽  
Author(s):  
K. E. Gibbs ◽  
F. O. Morrison

The cuticle of T. telarius (L.) examined by light and electron microscopy and subjected to tests for chitin and lipids is shown to be a thin layer with a pattern of external ridges. It is about 1.25 microns thick measured in the troughs and twice that thickness measured at the ridges. The ridges average from 1 to 1.6 μ apart. There is no tectocuticle but an outside lipoid layer and a dark-staining non-chitinous epicuticular layer from 0.1 to 0.2 μ thick. A double-layered inner procuticle is present. The outer layer of the procuticle remains unstained in contrast to the dark-staining inner layer. The inside surface of the cuticle bears elevations or ridges opposite the external troughs. The epicuticle only is shed at molting. It bears the branched setae and over the eyes is striated, the ridges being about 0.14 microns apart. Either one or both layers of the procuticle contain chitin.


1963 ◽  
Vol s3-104 (65) ◽  
pp. 141-144
Author(s):  
E. H. SIDDIQUI

The structure of the cuticle of the cysticerci of 3 species of Taenia was studied by means of optical and electron microscopy. In all 3 species the cuticle is composed of 3 layers and covered with hair-like processes. The middle layer, which comprises the bulk of the cuticle, varies in thickness from head to bladder, but there are no differences in thickness between the species studied. The hairs are composed of a core representing an extension of the middle layer and are covered by a continuation of the outer layer. The arrangement of these hairs varies in the species studied.


Sign in / Sign up

Export Citation Format

Share Document