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  • Open Access

    ARTICLE

    Leaf blade anatomy and ultrastructure of six Simira species (Rubiaceae) from the Atlantic Rain Forest, Brazil

    TARSILA MARIA DA SILVA MORAES1, CLAUDIA FRANCA BARROS2, SEBASTIÃO JOSÉ DA SILVA NETO3, VALDIRENE MOREIRA GOMES4, MAURA DA CUNHA1*

    BIOCELL, Vol.33, No.3, pp. 155-165, 2009, DOI:10.32604/biocell.2009.33.155

    Abstract Simira is a predominantly woody Neotropical genus comprising 41 taxa, 16 of which occur in Brazil and eight of them in the southeastern region of Brazil. Leaf blades of Simira eliezeriana Peixoto, S. glaziovii (K. Schum.) Steyerm., S. grazielae Peixoto, S. pikia (K. Schum.) Steyerm., S. rubra (Mart.) Steyerm., S. sampaioana (Standl.) Steyerm. were collected in the southeastern region of Brazil and fixed according to usual methods for light and electron microscopy. The leaf blades show typical characteristics of the Rubiaceae family as dorsiventral mesophyll and paracytic stomata. The presence of two bundle sheaths that extend to the upper epidermal layer, More >

  • Open Access

    ARTICLE

    Brief Communication : Spherites in the midgut epithelial cells of the sugarcane borer parasitized by Cotesia flavipes

    DANIELA DE OLIVEIRA PINHEIRO*, HÉLIO CONTE**, ELISA APARECIDA GREGÓRIO*

    BIOCELL, Vol.32, No.1, pp. 61-67, 2008, DOI:10.32604/biocell.2008.32.061

    Abstract Diatraea saccharalis, the main pest of sugarcane, has been controlled by Cotesia flavipes. Very little is known about the effect of parasitism on the host organs, including the midgut. The Lepidoptera midgut epithelium is composed of columnar, goblet, regenerative, and endocrine cells. Spherites have been described in columnar and regenerative cells of several Lepidoptera species, and presented a lot of functional meaning. We identified spherites in the midgut epithelial cells of non-parasitized D. saccharalis larvae analyzed the effect of parasitism on spherite morphology and distribution along the length of the midgut. Midgut fragments of both non-parasitized and parasitized… More >

  • Open Access

    ARTICLE

    Morphology and structure of the pollen cone and pollen grain of the Araucaria species from Argentina

    GEORGINA M. DEL FUEYO1, Marta A. CACCAVARI1,2, ELIZABETH A. DOME1

    BIOCELL, Vol.32, No.1, pp. 49-60, 2008, DOI:10.32604/biocell.2008.32.049

    Abstract The pollen cone and the pollen grain of the two Argentinean species of Araucaria are described with LM, SEM and TEM. Primordia of pollen cones are formed in April and May and reach maturity by mid-October in A. angustifolia (Bert.) O. Kuntze and by mid-November in A. araucana. (Mol.) K. Koch. Characters of the mature pollen cones and microsporophylls between both taxa are clearly differentiated. Pollen grains are spheroidal-subspheroidal, inaperturate, and asaccate with granulate exine and a subequatorial annular area that corresponds to the sexine thickness. Sculpturing consists of irregularly dispersed granules that are sometimes fused to each More >

  • Open Access

    ARTICLE

    An ultrastructural study of spermiogenesis in two species of Sitophilus (Coleoptera: Curculionidae)

    KHESLLER PATRÍCIA OLÁZIA NAME, GIULIANO PAGY FELIPE DOS REIS, SÔNIA NAIR BÁO

    BIOCELL, Vol.31, No.2, pp. 229-236, 2007, DOI:10.32604/biocell.2007.31.229

    Abstract The spermiogenesis of Sitophilus zeamais and Sitophilus oryzae, the maize and the rice weevil, respectively, was studied by light microscopy and scanning and transmission electron microscopy. Sitophilus spp. is the most widespread and destructive primary pest of stored cereals in the world. The spermiogenesis occurs within cysts. There are approximately 256 germ line cells per cyst. Inside each cysts, all the spermatids are in the same stage of maturation. The ultrastructure of the spermatozoa of S. zeamais and S. oryzae is similar to that described for other beetles. The head is formed by a three-layered acrosome with the perforatorium, the More >

  • Open Access

    ARTICLE

    Ultrastructural analysis and identification of membrane proteins in the free-living amoeba Difflugia corona

    MARCELO SILVA-BRIANO1 , SANDRA LUZ MARTÍNEZ-HERNÁNDEZ1 , ARACELI ADABACHE-ORTÍZ1 , JAVIER VENTURA-JUÁREZ2 , EVA SALINAS3 , J. LUIS QUINTANAR4

    BIOCELL, Vol.31, No.2, pp. 225-228, 2007, DOI:10.32604/biocell.2007.31.225

    Abstract Syntaxin-1 and 25-kDa Synaptosome-associated Protein (SNAP-25) are present in the plasma membrane of several different secretory cell types and are involved in the exocytosis process. In this work, the free-living amoeba Difflugia corona was studied in relation to ultrastructure, structural membrane proteins, and proteins such as Syntaxin-1 and SNAP-25. Our results obtained by scanning electron microscopy in the amoeba without its theca, showed many membrane projections and several pore-like structures. Using immunocytochemistry, we found structural proteins Syntaxin-1 and SNAP-25. More >

  • Open Access

    ARTICLE

    Brief Note : Cytochemical localization of acid phosphatase in Stigeoclonium tenue (Chaetophorales, Chlorophyceae)

    KARINA M. MICHETTI1,2, PATRICIA I. LEONARDI1,3, EDUARDO J. CÁCERES1,4

    BIOCELL, Vol.30, No.3, pp. 491-496, 2006, DOI:10.32604/biocell.2006.30.491

    Abstract Nonspecific acid phosphatases are a group of enzymes whose activity increases the availability of exogenous and endogenous orthophosphate either through extra- or intracellular hydrolysis of phosphate compounds. Our study demonstrates the activity of acid phosphatases in the filamentous freshwater alga Stigeoclonium tenue. These enzymes were detected following a cerium-based method in which cerium was used as an orthophosphate-capture reagent. In thalli from S. tenue from the natural environment, acid phosphatases were found in the longitudinal cell wall, plasmalemma, and vacuole. In thalli from Bold’s Basal Medium culture, these enzymes were found mainly in the plasmalemma; they were More >

  • Open Access

    ARTICLE

    Herbicide effects on cuticle ultrastructure in Eleusine indica and Portulaca oleracea

    ROSANA N. MALPASSI

    BIOCELL, Vol.30, No.1, pp. 51-56, 2006, DOI:10.32604/biocell.2006.30.051

    Abstract Eleusine indica and Portulaca oleracea are two common weeds in peanut crops in southern Córdoba. Two chemicals are frequently used to control them, quizalofop for grasses and lactofen for dicots. The objective is to study the effects of quizalofop and lactofen on cuticle ultrastructure in E. indica and P. oleracea, respectively. In the lab, quizalofop was applied on E. indica and lactofen on P. oleracea. Three plant categories were analyzed in each species: 3, 1-2, and no tiller in E. indica, and 8, 6, and 2 nomophylls in P. oleracea. Leaf samples from both species were collected at 7 and 16 days post-application… More >

  • Open Access

    ARTICLE

    Structural and ultrastructural characterization of zebu (Bos indicus) spermatozoa

    MARIA CAROLINA AQUINO LUQUE, SÔNIA NAIR BÁO

    BIOCELL, Vol.30, No.1, pp. 33-38, 2006, DOI:10.32604/biocell.2006.30.033

    Abstract The ultrastructure of normal, ejaculated spermatozoa of Bos indicus was studied by means of electron microscopy, being evaluated in two principal parts, the head and the tail. The head is flat, oval or paddle-shaped with a square base, which provides a concave recess for the insertion of the tail. The acrosome tightly covers the anterior two thirds of the nucleus. A distinct unilateral acrosomal bulge was observed along the apical edge of the head. The equatorial region demarcates the acrosome from the post-equatorial region that covers the caudal one third of the nucleus. The classical 9+9+2 More >

  • Open Access

    ARTICLE

    Ubisch bodies and pollen ontogeny in Oxalis articulata Savigny

    SONIA ROSENFELDT, BEATRIZ G. GALATI

    BIOCELL, Vol.29, No.3, pp. 271-278, 2005, DOI:10.32604/biocell.2005.29.271

    Abstract The correlation between the ontogeny of Ubisch bodies and pollen development in Oxalis articulata was studied with Transmission Electron Microscopy (TEM). The ultrastructural changes observed during the different stages of development in the tapetal cells are related to Ubisch bodies, sporopollenin and pollen-kitt formation. The pro-orbicules have the appearance of lipid globuli and their formation is related to the endoplasmic reticulum of rough type (ERr). The lipid globules or pro-orbicules disappear in the mature Ubisch bodies, and the places that they occupied remain free of contents or with pollen-kitt. More >

  • Open Access

    ARTICLE

    Fine structural analysis of the epithelial cells in the hepatopancreas of Palaemonetes argentinus (Crustacea, Decapoda, Caridea) in intermoult

    LILIANA G. SOUSA1, ELENA I. CUARTAS2, ANA MARÍA PETRIELLA1, 3

    BIOCELL, Vol.29, No.1, pp. 25-31, 2005, DOI:10.32604/biocell.2005.29.025

    Abstract The aim of this study is to describe the ultrastructure of the hepatopancreas of P. argentinus in intermoult. P. argentinus hepatopancreas was studied using standard TEM techniques. Each tubule consists of four cellular types: E (embryonic), F (fibrillar), R (resorptive) and B (blister like). E-cells have embryonic features and some of them were found in mitosis. F, R and B cells possess an apical brush border. F-cells have a central or basal nucleus, a conspicuous RER, and dilated Golgi cisternae. R cells show a polar organization of organelles in three areas: apical, with numerous mitochondria and sER… More >

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