scholarly journals Morphology, anatomy and ultrastructure of yarrow (Achillea millefolium L.) floral nectaries

2012 ◽  
Vol 59 (1) ◽  
pp. 17-28 ◽  
Author(s):  
Aneta Sulborska ◽  
Elżbieta Weryszko-Chmielewska
Keyword(s):  
Cell Ultrastructure ◽  
Achillea Millefolium ◽  
Secretory Cells ◽  
Vascular Bundles ◽  
Cell Nuclei ◽  
Golgi Bodies ◽  
Glandular Cells ◽  
A Cell ◽  
Electron Microscopes ◽  
Big Cell

The studies focused on the morphological and anatomical features as well as those related to the ultrastructure of nectary cells <i>Achillea millefolium</i> Asteraceae family. The nectary presence was confirmed only in the disk flowers at the pistil style base. The micromorphology of nectaries was investigated in SEM, and structure was observed in a light and transmission electron microscopes. A number of layers composing a gland, the size and shape of epidermal and glandular cells were determined. The secretory cell ultrastructure was analyzed. The discoidal nectary gland observed from above had a pentagonal shape, 181.5 µm height and 299.4 µm diameter. It was built of the monolayer epidermis and 6 layers of the secretory cells on average. The glandular cells appeared to be bigger (27 µm) than the epidermal cells (22 µm), a cell shape in both tissues differed as well. The nectar secretion occured through the modified stomata. The stomata cells were at distinguishable greater size and raised above the surface of epidermis. The nectaries were supplied by the vascular bundles running from the pistil style up to the nectary base, not getting into the gland. In the cells of the nectary epidermis observed in TEM the big cell nuclei, numerous plastids, mitochondria and vacuoles with fibrous secretion deposits and vesicular structures were found. In the cells of the nectary secretory tissue there were dense cytoplasm, many plastids, mitochondria, Golgi bodies and the extensive network of the endoplasmic reticulum.

scholarly journals Distribution and structure of internal secretory reservoirs on the vegetative organs of Inula helenium L. (Asteraceae)

2012 ◽  
Vol 60 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Aneta Sulborska
Keyword(s):  
Cross Sections ◽  
Light And Electron Microscopy ◽  
Secretory Cells ◽  
Vascular Bundles ◽  
Vegetative Organs ◽  
Full Flowering ◽  
Secretory Cavities ◽  
Inula Helenium ◽  
Glandular Cells ◽  
Large Central Vacuole

The aim of the study was to investigate the structure and topography of endogenous secretory tissues of <i>Inula helenium</i> L. By using light and electron microscopy, morphological and anatomical observations of stems, leaves and rhizomes were made. It was shown that in the stems secretory cavities were situated in the vicinity of phloem and xylem bundles. The number of the reservoirs reached its maximum value (34) at shoot flowerig termination, whereas the cavities with the largest diameter were observed at full flowering stage (44.6 µm). In the leaf petioles and midribs, the reservoirs also accompanied the vascular bundles, and their number and size increased along with the growth of the assimilation organs. Observations of the cross sections of the rhizomes revealed the presence of several rings of secretory reservoirs. The measurements of the cavities showed that as a rule the reservoirs with a larger dimension were located in the phelloderm, whereas the smallest ones in the xylem area. The secretory cavities located in the stems and leaves developed by schizogenesis, whereas the rhizome reservoirs were probably formed schizolisygenously. The cells lining the reservoirs formed a one - four-layered epithelium. Observed in TEM, the secretory cells of the mature cavities located in the rhizomes were characterised by the presence of a large central vacuole, whereas the protoplast was largely degraded. Fibrous elements of osmophilic secretion and numerous different coloured vesicles could be distinguished in it. The cell walls formed, from the side of the reservoir lumen, ingrowths into the interior of the epithelial cells. Between the cell wall and the plasmalemma of the glandular cells, a brighter periplasmatic zone with secretory vesicles was observed.

Ultrastructure of scent glands in larvae of Apateticus bracteatus (Hemiptera: Pentatomidae) and chemical composition of the secretion

1980 ◽  
Vol 58 (11) ◽  
pp. 2105-2115 ◽  
Author(s):  
Jean Percy ◽  
J. A. MacDonald ◽  
J. Weatherston
Keyword(s):  
Chemical Composition ◽  
Interstitial Cells ◽  
Secretory Cells ◽  
Scent Glands ◽  
Volatile Constituents ◽  
Dorsal Wall ◽  
Anterior Dorsal ◽  
Glandular Cells ◽  
Gland Function ◽  
Dorsal Abdominal Glands

The three dorsal abdominal glands in larvae of Apateticus bracteatus (Pentatomidae) secrete a mixture of compounds. Major volatile constituents of the secretion are identified, herein, as tridecane and 2-octenal. There are also trace amounts of 2-hexenal and two other unidentified compounds.Each of the glands has paired orifices that are located between tergites 3/4, 4/5, and 5/6, but only the most anterior gland is paired. In anterior glands of midinstar larvae, glandular cells associated with ducts, and interstitial glandular cells are distributed along the ventral walls of the reservoirs. In posterior glands, columnar glandular cells are located in the anterior dorsal wall of the reservoirs; secretory cells associated with ducts, and nonglandular interstitial cells are distributed throughout the ventral and posterior walls of the reservoirs. The interstitial glandular cells of the anterior gland and the columnar glandular cells of the middle and posterior glands contain cytoplasmic organelles characteristic of lipid-producing cells. In all glands the secretory cells associated with ducts secrete lipids. Evidence indicating the importance of Golgi and ER in secretion synthesis is presented. The reservoirs and ducts have a thin cuticular lining.The bearing of the results on present ideas of gland function in Heteroptera is discussed.

Ultrastructure of the female reproductive organs (ovary, vitellaria, and Mehlis' gland) of Halipegus eccentricus (Trematoda: Derogenidae)

1986 ◽  
Vol 64 (10) ◽  
pp. 2203-2212 ◽  
Author(s):  
Jon M. Holy ◽  
Darwin D. Wittrock
Keyword(s):  
Cell Types ◽  
Reproductive Organs ◽  
Golgi Body ◽  
Digenetic Trematode ◽  
Secretory Cells ◽  
Cortical Granules ◽  
Golgi Bodies ◽  
Transmission Electron ◽  
Vitelline Cells ◽  
Female Reproductive Organs

The female reproductive organs (ovary, vitellaria, and Mehlis' gland) of the digenetic trematode Halipegus eccentricus were studied by transmission electron microscopy. Oocytes entered diplotene while in the ovary and produced cortical granules and lipid bodies. Vitelline cells produced large amounts of eggshell protein but no yolk bodies. Two types of Mehlis' gland secretory cells were present, distinguishable by the morphology of their rough endoplasmic reticulum, Golgi bodies, and secretory bodies, and by the persistence of recognizable secretory material within the ootype lumen after exocytosis. In an attempt to standardize the nomenclature regarding the cell types of the Mehlis' gland, a classification that takes into account these four criteria is proposed. Two basic types of Golgi body organization were noted for the cells of the female reproductive system: a stack of flattened cisternae (Mehlis' gland alpha cells) and spherical Golgi bodies with vesicular cisternae (oocytes, vitelline cells, and Mehlis' gland beta cells).

Experimental Data on the Function of the Interstitium of the Gonads: Experiments with Cockerels

1947 ◽  
Vol s3-88 (2) ◽  
pp. 135-150
Author(s):  
J. W. SLUITER ◽  
G. J. VAN OORDT
Keyword(s):  
Experimental Data ◽  
Connective Tissue ◽  
Leydig Cells ◽  
Cell Types ◽  
Sex Hormone ◽  
Secretory Cells ◽  
Secretory Function ◽  
Glandular Cells ◽  
Male Sex ◽  
Secondary Function

1. The relative volumes of the testes and their components of 31 cockerels, 2-200 days old, were calculated and compared with the size of their increasing head appendages (Text-figs. 1a-d, 2); in addition, the effect of gestyl-administration on testes of cockerels of this age was investigated. 2. Several types of interstitial testis-cells could be distinguished morphologically and physiologically (Text-figs. 3-6 and Pl. 1); these cell-types were studied with different techniques and counted separately. 3. The main types of the interstitial cells are: (a) Lipoid cells, totally packed with lipoid globules. These cells, which are considered by many authors as fully developed Leydig cells, are not directly connected with the production of the male sex hormone; perhaps they have a secondary function in this respect, as cholesterolderivatives are stored in these cells (Pl. 1, Text-fig. 3a). (b) Secretory cells, characterized by the absence of lipoid vacuoles and the presence of numerous granular and filamentous mitochondria. These secretory cells, which produce the male sex hormone, can be divided into secretory cells A (Text-fig. 6a) without, and secretory cells B with, one large vacuole (Text-figs. 6b, 6c, 6d). 4. A considerable and partly intercellular storage of lipoids may take place at any age in the intertubular connective tissue (Text-figs. 3-4 and Pl. 1). 5. The number of the lipoid cells depends on the nutritive conditions of the animal and the development of its testes (Text-fig. 7). 6. In older cockerels most of the glandular cells lose their secretory function and pass over into lipoid storing cells. 7. Therefore we agree with Benoit, when he denies the occurrence of a ‘secretion de luxe’, but we cannot accept the presence of a ‘parenchyme de luxe’ in the testes of older cockerels.

The Symptoms and Histopathology of Poisoning by Maneb in Oncopeltus fasciatus (Dallas),

1965 ◽  
Vol 97 (11) ◽  
pp. 1200-1208 ◽  
Author(s):  
R. D. McMullen
Keyword(s):  
Oxygen Consumption ◽  
Malpighian Tubules ◽  
Oncopeltus Fasciatus ◽  
Secretory Cells ◽  
Cell Nuclei ◽  
Gut Epithelium

AbstractManeb (manganous ethylene bisdithiocarhamate) applied topically to Oncopeltus fasciatus nymphs causes death after 7 to 10 days. The gross symptoms of intoxication, histopathology and effect on oxygen consumption are described. Activities such as feeding and walking are slightly reduced after 24 hours and completely inhibited after 3 to 4 days. The tissues most severely affected by the treatment are the secretory cells of the mid-gut epithelium and the cells of the Malpighian tubules. These at first show extreme vacuolization, reduction of the size of cell nuclei and finally cytolysis. Oxygen consumption in vivo is reduced by the treatment.

scholarly journals Struktur Anatomi dan Uji Histokimia Terpenoid dan Fenol Dua Varietas Sirih Hijau (Piper betle L.)

BIOSCIENTIAE ◽  
2021 ◽  
Vol 17 (2) ◽  
pp. 1
Author(s):  
Gusti Puspa Dewi ◽  
Evi Mintowati Kuntorini ◽  
Eny Dwi Pujawati
Keyword(s):  
Copper Acetate ◽  
Anatomical Structure ◽  
Secretory Cells ◽  
Cell Diameter ◽  
Piper Betle ◽  
Vascular Bundles ◽  
Palisade Parenchyma ◽  
Betel Leaf ◽  
Epidermal Tissue ◽  
Pith Parenchyma

This study aims to determine the anatomical structure and histochemical test of terpenoid and phenol compounds in two varieties of green betel plants (Piper betle). Making leaves anatomical structure preparations using the fresh method, testing terpenoid compounds with 5% copper acetate, testing phenol with ferric trichloride 10% and some grains of sodium carbonate. The observations of the anatomical structure of green betel leaf varieties 1 and varieties 2 have similarities consisting of the upper epidermis, upper hypodermis, palisade parenchyma, parenchymal sponges, vascular bundles (xylem and phloem), sclerenchyma, cholenchyma, lower epidermis, lower hypodermis, secretory cells, trichoma, stoma and calcium oxalate crystals, and in varieties 2 look more trichomes. The anatomical structure of the variety 1 betel stem and varieties 2 are arranged from the outside in the direction of the epidermal tissue, colenchymal tissue, cortical bundles, sclerenchyma, cortex, medullary and peripheral vascular files, pith, the central part of the stem is a secretory gland. Phenol in betel vine varieties 1 and varieties 2 is positive in the secretion cell part which is spread in the parenchymal tissue of the mother's leaf bone and lamina, whereas in the stem is spread around the cortex and pith parenchyma. Positive secretion cells contain phenol not as much as secretory cells containing terpenoids. Based on quantitative observations the size of oil cell density and secretion cell diameter, the essential oils contained in the cell secretions in the leaves of variety 1 are more than varieties 2 while in the varieties 2, there are more varieties 1.

scholarly journals Brassinosteroids control root epidermal cell fate via direct regulation of a MYB-bHLH-WD40 complex by GSK3-like kinases

eLife ◽  
2014 ◽  
Vol 3 ◽  
Author(s):  
Yinwei Cheng ◽  
Wenjiao Zhu ◽  
Yuxiao Chen ◽  
Shinsaku Ito ◽  
Tadao Asami ◽  
...  
Keyword(s):  
Hair Cell ◽  
Cell Fate ◽  
Epidermal Cell ◽  
Hair Cells ◽  
Root Hair ◽  
Cell Nuclei ◽  
Brassinosteroid Signaling ◽  
Root Hair Formation ◽  
A Cell ◽  
Transcriptional Complex

In Arabidopsis, root hair and non-hair cell fates are determined by a MYB-bHLH-WD40 transcriptional complex and are regulated by many internal and environmental cues. Brassinosteroids play important roles in regulating root hair specification by unknown mechanisms. Here, we systematically examined root hair phenotypes in brassinosteroid-related mutants, and found that brassinosteroid signaling inhibits root hair formation through GSK3-like kinases or upstream components. We found that with enhanced brassinosteroid signaling, GL2, a cell fate marker for non-hair cells, is ectopically expressed in hair cells, while its expression in non-hair cells is suppressed when brassinosteroid signaling is reduced. Genetic analysis demonstrated that brassinosteroid-regulated root epidermal cell patterning is dependent on the WER-GL3/EGL3-TTG1 transcriptional complex. One of the GSK3-like kinases, BIN2, interacted with and phosphorylated EGL3, and EGL3s mutated at phosphorylation sites were retained in hair cell nuclei. BIN2 phosphorylated TTG1 to inhibit the activity of the WER-GL3/EGL3-TTG1 complex. Thus, our study provides insights into the mechanism of brassinosteroid regulation of root hair patterning.

Anatomy, ultrastructure, and functional morphology of the metathoracic tracheal defensive glands of the grasshopper Romalea guttata

1991 ◽  
Vol 69 (8) ◽  
pp. 2100-2108 ◽  
Author(s):  
Douglas W. Whitman ◽  
Johan P. J. Billen ◽  
David Alsop ◽  
Murray S. Blum
Keyword(s):  
Secretory Cell ◽  
Tactile Stimulation ◽  
Defensive Secretion ◽  
Smooth Endoplasmic Reticulum ◽  
Duct Cell ◽  
Secretory Cells ◽  
Glandular Tissue ◽  
Golgi Bodies ◽  
Romalea Guttata ◽  
Defensive Glands

In the lubber grasshopper Romalea guttata, the respiratory system produces, stores, and delivers a phenolic defensive secretion. The exudate is secreted by a glandular epithelium surrounding the metathoracic spiracular tracheal trunks. Embedded in the glandular tissue are multiple secretory units, each comprised of a basal secretory cell and an apical duct cell. Secretory cells have numerous mitochondria, a tubular, smooth endoplasmic reticulum, well-developed Golgi bodies, and a microvillilined vesicle thought to transfer secretion to the intracellular cuticular duct of a duct cell. Ducts empty into the metathoracic tracheal lumina where the exudate is stored behind the closed metathoracic spiracle. Tactile stimulation elicits secretion discharge, which begins when all spiracles except the metathoracic pair are closed and the abdomen is compressed. Increased hemostatic and pneumatic pressures drive air and secretion out of the spiracle with an audible hiss. Both metathoracic spiracles discharge simultaneously. The secretion erupts first as a dispersant spray, then as an adherent froth, and finally assumes the form of a slowly evaporating repellent droplet. Discharge force and number vary with eliciting stimuli, volume of stored secretion, and age, disturbance state, and temperature of the insect. Molting grasshoppers are unable to discharge because the stored exudate is lost with the shed cuticle. The advantages and limitations of a tracheal defensive system are discussed.

Preprophase Microtubule Bands in Some Abnormal Mitotic Cells of Wheat

1969 ◽  
Vol 4 (2) ◽  
pp. 397-420
Author(s):  
J. D. PICKETT-HEAPS
Keyword(s):  
Preprophase Band ◽  
Abnormal Development ◽  
Vascular Bundles ◽  
Root Tips ◽  
Stomatal Complexes ◽  
Abnormal Cells ◽  
A Cell ◽  
Asymmetrical Division ◽  
Wheat Tissues ◽  
Size Of Nuclei

Caffeine treatment of growing wheat tissues was used to form binucleate or polyploid cells; preprophase microtubules in subsequent division cycles in these and some other abnormal cells were then examined. In root tips, binucleate cells or those with greatly enlarged nuclei usually contained one transverse preprophase band of microtubules; sometimes this was slightly asymmetrical or skew, and less commonly two bands were seen. In coleoptile vascular bundles, there were generally two or more bands in the greatly elongated cells, these sometimes appearing in different planes. During formation of the stomatal complexes, preprophase microtubules were almost invariably found where expected, preceding abnormal development both in untreated and also in caffeine-treated material, regardless of the number, disposition or size of nuclei. This occurred even when wall stumps, formed during a previous abortive division, indicated that that previous division was also asymmetrical. It is concluded that the position(s) of preprophase band(s) of microtubules is not particularly influenced by the nucleus or nuclei, being more susceptible to external morphogenetic influences which can persist for some considerable time. Particularly in the case of stomatal complexes, a cell wall seems necessary to seal off or otherwise fulfil the tendency towards asymmetrical division.

Light as a Life Tool

2020 ◽  
pp. 58-81
Author(s):  
John Parrington
Keyword(s):  
Fluorescent Protein ◽  
Green It ◽  
Live Animal ◽  
New Science ◽  
Gene Coding ◽  
A Cell ◽  
Electron Microscopes ◽  
First Time ◽  
Protein Channels ◽  
The Brain

Visual light, and radiation of other frequencies, are highly important for scientific research. The first light microscopes made it possible for the first time to see that organisms from plants to humans are composed of cells. Electron microscopes have allowed scientists to study the structural components of cells in great detail, and even determine the shapes of individual proteins. Many lifeforms also use light to attract a mate or prey, or deter an attacker. Following the identification of the gene coding for the fluorescent protein that makes certain jellyfish glow green it has become possible to use this to genetically label proteins in a living cell, or even a live animal. This means that now the location of proteins in a cell can be determined exactly. A major recent step forward in neuroscience came with the discovery of protein channels in algae that conduct ions in response to light. By creating transgenic mice that have these proteins in their brain neurons, it is now possible to modulate the activity of these neurons by shining light into the brain though microscopic fibre optic cables. This new science of optogenetics allows neurons to be switched on or off experimentally. The optogenetic approach has been used to uncover the neural circuits involved in memory, pain and pleasure. In the future this technique might be used to treat physical pain or depression in people. Controversially, it might be also be misused, to supress memories, or even create completely false ones in people’s heads.

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