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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Spore germination in Dictyostelium discoideum

Cotter, David Allen, January 1965 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1965. / eContent provider-neutral record in process. Description based on print version record. Bibliography: l. 71-73.
22

Analysis of nondisjunction induced by the r-X1deficiency and the effect of nullisomy during microsporogenesis in Zea mays

Zhao, Zuo-Yu. Weber, David F. January 1988 (has links)
Thesis (Ph. D.)--Illinois State University, 1988. / Title from title page screen, viewed September 14, 2005. Dissertation Committee: David F. Weber (chair), Herman E. Brockman, Robert W. Briggs, Alan J. Katz, Glen E. Collier. Includes bibliographical references (leaves 104-111) and abstract. Also available in print.
23

Timing of enzyme synthesis during outgrowth of spores of Bacillus cereus strain T

Steinberg, William, January 1967 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1967. / Typescript. Vita. Description based on print version record. Includes bibliographical references.
24

Initiation of bacterial spore germination

Vary, James C. January 1967 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1967. / Typescript. Vita. Description based on print version record. Includes bibliographical references.
25

Factors influencing spore and cell size in Dictyostelium discoideum

Weber, Allen Thomas, January 1967 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1967. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
26

Surface characteristics of conidia from monosporous cultures of Penicillium Digitatum and Aspergillus Nidulans Var. Echinulatus

Fuji, Raymond Kunito 01 August 1969 (has links)
The purpose of this investigation was to evaluate the possible taxonomic significance of the "rodlet" patterns and spore wall configurations of conidia from monosporous cultures of Penicillium digitatum Saccardo and Aspergillus nidulans Eidam var. echinulatus Fennell & Raper. Freeze-etching the conidiospores from single spore isolates of these fungi revealed that spore wall patterns and configurations vary much too greatly to be of taxonomic importance on the strain and subspecies level. Environmental factors and genetic influences are discussed as possible mechanisms causing the variations of the spore wall configurations. A membrane-like structure that covers the "rodlet" patterns and which hinders spore surface investigations of conidia of these fungi is discussed.
27

Fixation of dormant tilletia teliospores for thin sectioning

Gardner, John Scott 01 April 1976 (has links)
Dormant Tilletia caries teliospores in fixative solution or distilled water were frozen onto specimen chucks of an FTS Sorvall- Christensen frozen thin sectioner and cut or fractured at various temperatures (-20 to -75 C) and thickness settings (10, 15, 20, and 25 um). Cytoplasm of dormant spores was well preserved and organelles were found to differ from those of germinated spores in morphology. Irregular electron dense and electron opaque areas of lipid bodies were sometimes evident in dormant and germinating Tilletia caries teliospores. When dormant teliospores were sectioned in buffered fixative, lipids had an appearance similar to lipids in thin sections of germinated teliospores. When dormant and germinating teliospores were sectioned in frozen distilled water and subsequently fixed, "mop-like" structures were evident. The "mop-like" structures were made up of a lamellar substructure with 6-10 nm center-to-center spacing. Lipid bodies of dormant and germinating teliospores often appear to have half-unit membranes surrounding them.
28

Miospore biostratigraphy, sequence stratigraphy, and glacio-eustatic response of the Borden Delta (Osagean; Tournaisian/Visean) of Kentucky and Indiana, U.S.A.

Richardson, Jeffrey G., January 2003 (has links)
Thesis (Ph. D.)--Ohio State University, 2003. / Title from first page of PDF file. Document formatted into pages; contains xvii, 275 p.: ill. Includes abstract and vita. Advisor: W.I. Ausich, Dept. of Geological Sciences. Includes bibliographical references (p. 186-208).
29

Basidiosporogenesis and developmental anatomy of spore release in the Russulales: a systematic interpretation

Miller, Steven L. January 1985 (has links)
Morphologically and anatomically the Russulales (Basidiomycetes) are a homogeneous group of higher fungi, which contains both ballistosporic and statismosporic, agaricoid and gasteroid taxa. Spore symmetry and ability to forcibly discharge spores are therefore fundamental systematic characteristics in the Russulales. Ballistosporic and statismosporic basidiosporogenesis however, has not been critically compared. Early and late basidiosporogenesis, spore-wall tegumentation, and differentiation of the hilar appendix were ultrastructurally characterized in species selected from eight genera of agaricoid and gasteroid Russulales including: Russula, Lactarius, Macowanites, Arcangeliella, Elasmomyces, Gymnomyces, Martellia, and Zelleromyces. Six spore-wall layers are present in developing spores in all genera. Two wall layers are associated with an evanescent pellicle and four wall layers are derived from the sterigma and young spore. The amyloid portion of the spore wall in the Russulales is an electron-translucent wall layer covered by an electron-dense surface layer. Ontogeny of spore-wall ornamentation is similar in all genera, however diversity in the degree of ornamentation and amyloidity results from differentiation and intermixing of the two outermost enduring wall layers. Establishment of early spore asymmetry in both ballistosporic- and statismosporic-heterotropic basidiospores is highly correlated with the presence of a hilar appendix body. Observation of a demarcated cytoplasmic region, reminiscent of the hilar appendix body, in asymmetric sterigmata of orthotropic Russulales suggests that basidiospore morphology and symmetry are variable features in the Russulales. Late spore development subsequent to nuclear migration is similar in orthotropic and heterotropic Russulales. Orthotropic basidiospores appear to be released from sterigmata upon breakdown of the sterigmata. Heterotropic basidiospores are released while sterigmata are intact. Plugging layers develop in both the sterigma and in the hilar appendix. The hilar appendix plugging material appears to be produced by a plug-forming body which originates in the spore, and possibly controls liquid droplet formation during ballistosporic discharge. Ballistosporic discharge appears to be a conservative phenomenon in most Basidiomycetes resulting from a prescribed sequence of biochemical and developmental processes. The use of ballistospory and statismospory in distinguishing families and genera must be re-evaluated in the Russulales. Recognition of the Lactariaceae and Russulaceae is discussed. / Ph. D.
30

Late Paleozoic lycopodiaceous megaspores of Brazil

Wilder, Nicéa Trindade January 1980 (has links)
No description available.

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