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UPV Theses and Dissertations

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    A taxonomic survey of epiphytes on Enhalus acoroides in Ali Cove, Taklong Island, Nueva Valencia, Guimaras
    Alojado, Ezra Nelson E. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1996-06)
    Epiphytes were collected from the blades of the seagrass Enhalus acoroides which were harvested from Ali Cove, Taklong Island, Guimaras. 20 epiphytic algae were identified with the aid of taxonomic keys. Of these, five belong to the Cyanophyceae, two to the Chlorophyceae, one to the Phaeophyceae, eight to the Rhodophyceae and four to the Bacillariophyceae. Thirteen specimens were identified to the species level and seven to the genus level only. Measurements of temperature, salinity and pH were taken at the study site during the collection
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    A preliminary study on the effect of neem (Azadirachta indica) seed extract on the reproductive potential of the female Friutfly (Drosophila melanogaster)
    Altea, Armee H. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1994-04)
    Eqqs, first instar larvae, and third instar larvae of fruit flies (D. melanogaster), were treated with 0%, 10%, and 15% neem seed extract. This resulted in reduced number of adults that emerged from treated embryos and larvae. Females following treatment crossed with untreated males have reduced number of progeny compared with control (untreated) females. Treatment of extract at three stages of development indicated that fertilized eggs were most affected by the extract. Females derived from treated eggs were sterile. The number of progeny produced by females treated during first instar stage were considerably reduced compared to controls. On the other hand, the number of progeny produced by females treated during third instar stage was not significantly different from controls. The results suggest that neem seed extract has active components which can reduce the reproductive potential of female fruit flies exposed to the chemicals particularly at the early stages of development.
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    A preliminary study on the extraction of alginic acid from three species of brown algae: Sargassum polycystum, Sargassum cristaefolium and Turbinaria sp. in Taklong Is.,Guimaras
    Adelantar, Geoffrey V. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1996-04)
    Three species of brown algae were harvested in Taklong Is., Guimaras. These were Sargassum polycystum, Sargassum cristaefolium, and Turbinaria sp. These brown algae were subjected to physical and chemical treatment to extract and compare the amount of their alginic acid in the form of sodium alginate. Four seaweed collections for extraction were made between August to December, 1995. Values obtained during the first three extractions gave almost similar results. S. polycystum exhibited the highest percentage yield of sodium alginate with a mean of 22.84%. It was followed by S. cristaefolium at 22.21%. Turbinaria sp. gave the lowest yield with a mean of 14.12%. The last extraction somehow showed a decrease in the percentage yield of all three samples. S. polycystum yielded just 20.00%, S. cristaefolium at 19.00% and Turbinaria sp. at just. 10.10%. Several factors may have contributed to the differences in the amount of alginic acid of the three species of brown algae. Among these are the inherent capability of the different species of brown algae to produce alginates, the thickness and sturdiness of the samples, the viscosity of the extracts, and seasonal changes.
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    A comparison on the effect of light on melanophore differentiation in the larval stage of frog, Hyla sp.
    Araneta, Merrie Celine E. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1996-03)
    Three set-ups were exposed to different experimental conditions namely: set-up A. under prolonged light: set-up B. under prolonged darkness: set-up C. under normal condition. Observation was done under the dissecting microscope from the first appearance of melanophores until the migration was stabilized. The pattern of differentiation was observed to be the same in all set-ups. only the distribution and the color intensity differred. B was the darkest and C was the lightest. It only showed that light could not, alter the pattern of melanophore differentiation, only the distribution.