FLOWER DEVELOPMENT OF EMPETRUM HERMAPHRODITUM (ERICACEAE), "БОТАНИЧЕСКИЙ ЖУРНАЛ"

2012 ◽  
pp. 475a-486
Author(s):  
N.A. VISLOBOKOV ◽  
D.D. SOKOLOFF ◽  
A.S. KORYAKIN
Keyword(s):  
Flower Development ◽  
Floral Morphology ◽  
Corolla Tube ◽  
Character State ◽  
Electron Microscopic ◽  
Secondary Loss ◽  
Empetrum Hermaphroditum ◽  
Scanning Electron Microscopic ◽  
Electron Microscopic Data ◽  
Scanning Electron

Flowers of most Ericaceae are characterized by pentamery and sympetaly. Empetrum is one of the members of Ericaceae that deviate from this flower groundplan. Due to differences in floral morphology, earlier classifications places Empetrum in a distinct family, Empetraceae belonging to various orders. Perianth of Empetrum is composed by two trimerous whorls of free phyllomes. Different authors interpret it as either simple (with tepals) or double (with sepias and petals). The paper presents scanning electron microscopic data on flower development in Empetrum hermaphroditum. Developmental data suggest that the perianth should be interpreted as double one. Petals are free in anthetic flower and rudiments of corolla tube are not found in early stages of flower development. In this respect, Empetrum differs from some other Ericaceae with free petals in anthetic flowers (such as Rhodonendron tomentosum- Leins, 1964) where rudiments of corolla tube can be traced early in development. In both cases, secondary loss of sympetaly should be assumed. In contrast to another, unrelated genus of Ericaceae bearing flowers with three petals (Tripetaleia-Nishino, 1988) no signs of 'cryptic pentamery' can be traced in flowers of Empetrum. Different patterns of carpel arrangement are documented in Empetrum. Polymerous gynoecium of Empetrum is interpreted as an apomorphic character state derived from a gynoecium isomerous to perianth whorls.

scholarly journals Systematic value of the ultrastructure of the sucker surface in the squid family Mastigoteuthidae (Mollusca: Cephalopoda)

1995 ◽  
Vol 65 (2) ◽  
pp. 65-77
Author(s):  
Mario Alejandro Salcedo-Vargas
Keyword(s):  
Deep Sea ◽  
Northwest Pacific ◽  
Electron Microscopic ◽  
Scanning Electron Microscopic ◽  
Electron Microscopic Data ◽  
Scanning Electron

The ultrastructure of the sucker surface is described and its systematic value for mastigoteuthid squids, which bear minute suckers, is considered. An introduction to sucker terms is given and a redefinition of these terms is attempted. Using scanning electron microscopic data, two genera and four subgenera of Mastigoteuthidae from the Northwest Pacific are distinguished. The presence of “cushions” in the sucker is discussed and considered as a character important for understanding adaptations of cephalopods to the deep-sea.

Scanning Electron Microscopic Study of the Cell Surface

1969 ◽  
Vol 27 ◽  
pp. 36-37 ◽  
Author(s):  
Toichiro Kuwabara
Keyword(s):  
Tissue Fluid ◽  
Biological Application ◽  
Biological Structure ◽  
Electron Microscopic ◽  
Surface Appearance ◽  
Minute Amount ◽  
Scanning Electron Microscopic Study ◽  
Scanning Electron Microscopic ◽  
True Structure ◽  
Scanning Electron

Although scanning electron microscopy has a great potential in biological application, there are certain limitations in visualization of the biological structure. Satisfactory techniques to demonstrate natural surfaces of the tissue and the cell have been reported by several investigators. However, it is commonly found that the surface cell membrane is covered with a minute amount of mucin, secretory substance or tissue fluid as physiological, pathological or artefactual condition. These substances give a false surface appearance, especially when the tissue is fixed with strong fixatives. It seems important to remove these coating substances from the surface of the cell for demonstration of the true structure.

A scanning electron microscopic study on dissolving process of cholesterol gallstones by chenodeoxycholic acid (CDCA)

1978 ◽  
Vol 36 (2) ◽  
pp. 522-523
Author(s):  
T. Kanetaka ◽  
M. Cho ◽  
S. Kawamura ◽  
T. Sado ◽  
K. Hara
Keyword(s):  
Electron Microscope ◽  
Chenodeoxycholic Acid ◽  
Outer Surface ◽  
Electron Microscopic ◽  
Cholesterol Gallstones ◽  
The Core ◽  
Scanning Electron Microscopic Study ◽  
Scanning Electron Microscopic ◽  
Acceleration Voltage ◽  
Scanning Electron

The authors have investigated the dissolution process of human cholesterol gallstones using a scanning electron microscope(SEM). This study was carried out by comparing control gallstones incubated in beagle bile with gallstones obtained from patients who were treated with chenodeoxycholic acid(CDCA).The cholesterol gallstones for this study were obtained from 14 patients. Three control patients were treated without CDCA and eleven patients were treated with CDCA 300-600 mg/day for periods ranging from four to twenty five months. It was confirmed through chemical analysis that these gallstones contained more than 80% cholesterol in both the outer surface and the core.The specimen were obtained from the outer surface and the core of the gallstones. Each specimen was attached to alminum sheet and coated with carbon to 100Å thickness. The SEM observation was made by Hitachi S-550 with 20 kV acceleration voltage and with 60-20, 000X magnification.

A Comparative Study of Fractographic Replicas

1974 ◽  
Vol 32 ◽  
pp. 566-567
Author(s):  
Loren Anderson ◽  
Pat Pizzo ◽  
Glen Haydon
Keyword(s):  
Electron Microscopy ◽  
Electron Microscopic Examination ◽  
Direct Examination ◽  
Electron Microscopic ◽  
Reliable Technique ◽  
Service Failures ◽  
Transmission Electron ◽  
Mode Of Failure ◽  
Scanning Electron Microscopic ◽  
Scanning Electron

Transmission electron microscopy of replicas has long been used to study the fracture surfaces of components which fail in service. Recently, the scanning electron microscope (SEM) has gained popularity because it allows direct examination of the fracture surface. However, the somewhat lower resolution of the SEM coupled with a restriction on the sample size has served to limit the use of this instrument in investigating in-service failures. It is the intent of this paper to show that scanning electron microscopic examination of conventional negative replicas can be a convenient and reliable technique for determining mode of failure.

A Scanning Electron Microscopic Study of the Uriniferous Tubules

1973 ◽  
Vol 31 ◽  
pp. 622-623
Author(s):  
Peter M. Andrews
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Renal Glomerulus ◽  
Electron Microscopic ◽  
Vascular Perfusion ◽  
Scanning Electron Microscopic Study ◽  
Scanning Electron Microscopic ◽  
Collecting Tubules ◽  
Bowman's Capsule ◽  
Scanning Electron

Although there have been a number of recent scanning electron microscopic reports on the renal glomerulus, the advantages of scanning electron microscopy have not yet been applied to a systematic study of the uriniferous tubules. In the present investigation, scanning electron microscopy was used to study the ultrastructural morphology of the proximal, distal, thin loop, and collecting tubules. Material for observation was taken from rat kidneys which were fixed by vascular perfusion, sectioned by either cutting or fracturing technigues, and critically point dried.The brush border characterising proximal tubules is first detected on the luminal surface of Bowman's capsule adjacent to the urinary pole orifice. In this region one frequently finds irregular microvilli characterized by broad and flattened bases with occasional bulbous structures protruding from their surfaces.

Human Stapes Crura: Normal Ultrastructure. Scanning Electron Microscopic Findings

1975 ◽  
Vol 33 ◽  
pp. 528-529
Author(s):  
M.D. Graham
Keyword(s):  
Electron Microscope ◽  
Surgical Treatment ◽  
Scanning Electron Microscope ◽  
Osmic Acid ◽  
Human Cadaver ◽  
Electron Microscopic ◽  
Scanning Electron Microscopic ◽  
Normal Human ◽  
Microscopic Findings ◽  
Scanning Electron

The recent development of the scanning electron microscope has added great impetus to the study of ultrastructural details of normal human ossicles. A thorough description of the ultrastructure of the human ossicles is required in order to determine changes associated with disease processes following medical or surgical treatment.Human stapes crura were obtained at the time of surgery for clinical otosclerosis and from human cadaver material. The specimens to be examined by the scanning electron microscope were fixed immediately in the operating room in a cold phosphate buffered 2% gluteraldehyde solution, washed with Ringers, post fixed in cold 1% osmic acid and dehydrated in graded alcohol. Specimens were transferred from alcohol to a series of increasing concentrations of ethyl alcohol and amyl acetate. The tissue was then critical point dried, secured to aluminum stubs and coated with gold, approximately 150A thick on a rotating stage in a vacuum evaporator. The specimens were then studied with the Kent-Cambridge S4-10 Scanning Electron Microscope at an accelerating voltage of 20KV.

A Scanning Electron Microscopic Study of Pro-Vascular Cellular Morphology in Chaetophora Incressata

1985 ◽  
Vol 43 ◽  
pp. 638-639
Author(s):  
A. E. Hotchkiss ◽  
A. T. Hotchkiss ◽  
R. P. Apkarian
Keyword(s):  
Green Algae ◽  
Vascular Plants ◽  
Vascular System ◽  
Higher Plants ◽  
Wall Structure ◽  
Electron Microscopic ◽  
Physiological Processes ◽  
Scanning Electron Microscopic Study ◽  
Scanning Electron Microscopic ◽  
Scanning Electron

Multicellular green algae may be an ancestral form of the vascular plants. These algae exhibit cell wall structure, chlorophyll pigmentation, and physiological processes similar to those of higher plants. The presence of a vascular system which provides water, minerals, and nutrients to remote tissues in higher plants was believed unnecessary for the algae. Among the green algae, the Chaetophorales are complex highly branched forms that might require some means of nutrient transport. The Chaetophorales do possess apical meristematic groups of cells that have growth orientations suggestive of stem and root positions. Branches of Chaetophora incressata were examined by the scanning electron microscope (SEM) for ultrastructural evidence of pro-vascular transport.

Haemostatic Clot Formation at Anastomosis of Synthetic Venous Graft in Defibrinogenated Dogs: A Scanning Electron Microscopic Study

1981 ◽  
Vol 45 (03) ◽  
pp. 276-281 ◽  
Author(s):  
S Ishimaru ◽  
E Berglin ◽  
H-A Hansson ◽  
A-C Teger-Nilsson ◽  
G William-Olsson
Keyword(s):  
Vena Cava ◽  
Treated Group ◽  
Control Group ◽  
Electron Microscopic ◽  
Scanning Electron Microscopic Study ◽  
Fibrin Network ◽  
Scanning Electron Microscopic ◽  
Expanded Polytetrafluoroethylene Graft ◽  
Morphological Differences ◽  
Scanning Electron

SummaryA segment of the inferior vena cava was replaced by an expanded polytetrafluoroethylene graft in 13 dogs. Five of them served as a control group, while the other 8 were moderately or severely defibrinogenated with subcutaneous batroxobin. Plasma fibrinogen decreased to extremely low values throughout the experiment in the defibrinogenated dogs except in the moderately treated group in which it temporarily rose to 0.72-0.87 g/1 on the first postoperative day.Scanning electron microscopic observations of the haemostatic clot formed at the anastomoses of the graft revealed no significant morphological differences in platelet adhesion and/or aggregation between the three groups. These findings confirmed that platelets play a key role in primary haemostasis during defibrinogenation.The fibrin network was slightly diminished and only short fibrin filaments could be seen in the moderately and severely defibrinogenated groups respectively. These differences in composition of the clots are discussed in relation to their haemostatic capacity.

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