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Theories Of The Origin And Early Evolution Of Life, David A. Dewitt Jan 2000

Theories Of The Origin And Early Evolution Of Life, David A. Dewitt

Faculty Publications and Presentations

After the theory of spontaneous generation was discredited, only religious explanations were offered to explain the origin of life. Alexander Oparin (1894-1980), an atheist, suggested that natural chemical reactions produced biological molecules that came together to form the first living thing. Later, Stanley Miller tested this hypothesis and produced chemical "building blocks" but not life itself. In spite of much progress, there is still no clear consensus on how life originated on Earth. Some scientists are even looking to outer space for the origin of life.

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Relationship Between Pea Crab (Pinnotheres Maculatus) Parasitism And Gonad Mass Of The Bay Scallop (Argopecten Irradians), Paul A.X. Bologna, Kenneth L. Heck Jan 2000

Relationship Between Pea Crab (Pinnotheres Maculatus) Parasitism And Gonad Mass Of The Bay Scallop (Argopecten Irradians), Paul A.X. Bologna, Kenneth L. Heck

Department of Biology Faculty Scholarship and Creative Works

We investigated the prevalence of pea crabs (Pinnotheres maculatus) in bay scallops (Argopecten irradians) from 1994 through 1996 in a scallop population from St. Joseph Bay, Florida. We also assessed their impacts on scallop reproductive potential. Our results showed that prevalence in bay scallops varied between 0 and 20% and were extremely low during 1996 (< 2%). Comparing Gonadal-Somatic Indices (GSI) between infested and non-infested bay scallops in samples assessed the impact of pinnotherid parasitism. Results showed that GSI was significantly reduced in infested individuals compared to non-infested individuals of the same size range (t12 = 2.3, P < 0.04). These results suggest that P. maculatus infestation may lower the reproductive potential of individual scallops, but the low rates of parasitism may only minimally impact the host population.

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Nonspecific Esterase Patterns Of Rattus Norvegicus(Berkenhout, 1769) In Western Turkey, Reyhan Çolak, Nuri̇ Yi̇ği̇t, Ercüment Çolak, Mustafa Sözen, Şaki̇r Özkurt Jan 2000

Nonspecific Esterase Patterns Of Rattus Norvegicus(Berkenhout, 1769) In Western Turkey, Reyhan Çolak, Nuri̇ Yi̇ği̇t, Ercüment Çolak, Mustafa Sözen, Şaki̇r Özkurt

Turkish Journal of Biology

Nonspecific esterases in the muscle, heart, kidney and liver tissues of wild rats (Rattus norvegicus) were examined by horizontal starch gel electrophoresis. Zymogram bands corresponding to Es-10 and Es-4 in the muscle, heart, kidney and liver homogenates, Es-3 and Es-17 in the kidney and liver, Es-18 in the liver tissue, Es-15 in kidney and liver, Es-2 in the muscle and heart, Es-16 in the heart tissue were detected. These findings showed that nonspecific esterases are very polymorphic and tissue-specific, and are not of taxonomic importance for the populations of Rattus norvegicus.

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A Rapid, Simple & Inexpensive Experiment In Gel Filtration Chromatography, Roger Sauterer, Jody Jones Jan 2000

A Rapid, Simple & Inexpensive Experiment In Gel Filtration Chromatography, Roger Sauterer, Jody Jones

Research, Publications & Creative Work

We have developed a simple and inexpensive experiment using gel filtration chromatography that can be performed in less than 90 minutes. This procedure not only provides students with hands-on experience in both the preparation and use of chromatography columns, but also uses colored molecules to provide dramatic visual confirmation of the process of size-exclusion chromatography. Additionally, the column can be calibrated using molecules of known molecular weights and can then be used to estimate the molecular weights of unknown samples. Our gel filtration experiment costs only a fraction of that of commercially marketed laboratory exercises. A basic understanding of methods …

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A Quantitative And Qualitative Study On The Phytoplankton Of Palandöken Pond, Hasan Gürbüz, Zekeri̇ya Altuner Jan 2000

A Quantitative And Qualitative Study On The Phytoplankton Of Palandöken Pond, Hasan Gürbüz, Zekeri̇ya Altuner

Turkish Journal of Biology

In this research, the phytoplankton community of Palandöken pond was investigated quantitatively and qualitatively in samples taken vertically from the surface to 10 m depth between October 1990 and October 1992. The physical and chemical properties of the pond water were also determined. 99 taxa were determined in the phytoplankton and the proportions of them were as follows: Bacillariophyta 79%, Chlorophyta 10%, Cynophyta 6%, Euglenophyta 5%. The phytoplankton generally increased in the spring and early fall whereas in the summer and late fall it decreased. Physical factors had the greatest effect on phytoplankton growth.

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A Quantitative And Qualitative Study On The Benthic Algal Floraof Palandöken Pond, Hasan Gürbüz Jan 2000

A Quantitative And Qualitative Study On The Benthic Algal Floraof Palandöken Pond, Hasan Gürbüz

Turkish Journal of Biology

In this study, the composition and density of the benthic algae and seasonal variations of the benthic algae of Palandöken Pond were determined between September 1990 and September 1992. Samples were collected from two previously selected sampling sites. It was found that Bacillariophyta was the dominant benthic algal group in this pond. During our investigation a total of 160 taxa were identified and 135 them were composed of epipelic algae. The percentages of algal groups were as follows: Bacillariophyta 57%, Cholorphyta 11% and Euglenophyta5%. It was found that there were plenty of epipelic algal species living together with epiphytic and …

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The Monthly Variations Of Blood Glucose Level Of Capoeta Tinca Capoeta(Heckel, 1843) In Çoruh Basin-Oltu Stream, Ayhan Yildirim, Mustafa Türkmen, İrfan Altuntaş Jan 2000

The Monthly Variations Of Blood Glucose Level Of Capoeta Tinca Capoeta(Heckel, 1843) In Çoruh Basin-Oltu Stream, Ayhan Yildirim, Mustafa Türkmen, İrfan Altuntaş

Turkish Journal of Biology

In this study, the monthly variation of blood glucose level of Capoeta tinca caught from in Çoruh Basin - Oltu Stream, between Augist 1995 and June 1996 was determined. It was determined that the average blood glucose level was 86.19±3.86 mg/dl in males and 83.58±3.77 mg/dl in females. The blood glucose level was highest (116.36±8.58 mg/dl) in April, and lowest (51.00±7.10 mg/dl) in June.

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The Inhibition Effect Of Yoghurt Starter Culture Metabolites, Belma Aslim, Yavuz Beyatli, Kadi̇r Halkman Jan 2000

The Inhibition Effect Of Yoghurt Starter Culture Metabolites, Belma Aslim, Yavuz Beyatli, Kadi̇r Halkman

Turkish Journal of Biology

In this study effect of some separate and combined metabolic compounds produced by lactic acid were tested on food pathogenic and contaminant microorgnasms. For this study, five strains of each Lactobacillus bulgaricus and Streptococcus thermophilus were used. The inhibition effects of the metabolic products (lactic acid, hydrogen peroxide, acetaldehyde, diacetyl) produced by the stains on test bacteria ( Staphylococcus aureus, Escherichia coli) were determined. Also, a random combinations of the strains were prepared and the metabolic compounds produced by these cultures and their antimicrobial activities on tested bacteria were determined. By regarding the metabolic products mainly, the samples of lactic …

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Investigation Of Selected Industrially Important Enzymatic Activities Of Turkish Agricultural Mycoflora-I: Amylase, Lipase, Protease, Şemi̇nur Topal, Ceyda Pembeci̇, Mehli̇ka Borcakli, Mehmet Batum, Özlem Çelti̇k Jan 2000

Investigation Of Selected Industrially Important Enzymatic Activities Of Turkish Agricultural Mycoflora-I: Amylase, Lipase, Protease, Şemi̇nur Topal, Ceyda Pembeci̇, Mehli̇ka Borcakli, Mehmet Batum, Özlem Çelti̇k

Turkish Journal of Biology

In this context, fungi being a rich source in from metabolites point of view, their utilization possibilities in various area are investigated. Primary metabolites of the fungi representing Turkish agricultural mycoflora which belongs to our culture collections are determined and their importance with respect to industry will be evaluated. It is assumed that enzymes such as, protease, amylase, lipase, cellulase, xylanase, b-glucanase, pectinase of these moulds represent a potential source for food industry. In this context, qualitative screening three of these enzymes producing abilities of relevant moulds are carried out. Methods used for enzyme determination cover, "Opacity Capacities in Deep …

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The Population Structure And Growth Properties Of Chalcalburnusmossulensis (Heckel, 1843) Caught From Askale Region Of River Karasu, Mustafa Türkmen, İhsan Akyurt Jan 2000

The Population Structure And Growth Properties Of Chalcalburnusmossulensis (Heckel, 1843) Caught From Askale Region Of River Karasu, Mustafa Türkmen, İhsan Akyurt

Turkish Journal of Biology

In this study, the population structure and growth properties of Chalcalburnus mossulensis (Heckel, 1843) caught from Askale Region of River Karasu betwen February 1996 and January 1997 were examined. The age composition of population varied between I and VI ages, and the most abundant age group was the third age group (42.13%). The population was composed of 51.74% females and 48.26% males. The fork length and the body weights of males and females varied between 8.9-18.1 cm, 3.6-67.9 g and 8.5-18.5 cm, 5.1-79.5 g respectively. The specific and relative growth for length and weight were maximum in the second age. …

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The Effects Of Malt Extract And Corn Strach On The Vegetativedevelopment And Morphology Of The Pleurotus Floridafovose Mycelia, Abdunnasir Yildiz Jan 2000

The Effects Of Malt Extract And Corn Strach On The Vegetativedevelopment And Morphology Of The Pleurotus Floridafovose Mycelia, Abdunnasir Yildiz

Turkish Journal of Biology

No statistical differences were determined in the effects of malt extract (ME) and corn strach (CS) doses on the vegetative development of mycelia (P>0.05). The mycelia in all gropus covered 9.0 cm agar plates in 9.0 days and some characteristic differences, development from (vertical or horizontal), cluster formation, tickening and tissue formations, were observed. In the group containing 2% CS, the mycelia formed a sparse development horizontally on the surface and center of the agar plate, whereas clustering, thickening and tissue formation wereobserved in the form of a thick zone on the edges of the petri dishes. In 1.5% …

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The Effect Of Olive Oil Mill Effluent On The Mitotic Cell Division And Total Protein Amount Of The Root Tips Of Triticum Aestivuml., Mehmet Aybeke, Göksel Olgun, Uğur Sidal, Dürdane Kolankaya Jan 2000

The Effect Of Olive Oil Mill Effluent On The Mitotic Cell Division And Total Protein Amount Of The Root Tips Of Triticum Aestivuml., Mehmet Aybeke, Göksel Olgun, Uğur Sidal, Dürdane Kolankaya

Turkish Journal of Biology

In this work sitotoxic and mutagenic effects Olive Oil Mill Effluent (OOME) on the root tips of Triticum aestivumL. were investigated. In this purpose, germination rate of seeds, mitotic division abnormalities and total protein amounts were evaluated. The seeds kept in various OOME concentrastions, it was determinated that germination rate decreased, whilst mitotic abnormalities and mitotic cell division frequency increased. Especially, the increased cell division frequency was of significance, almost several times higher than the control group. The cells having multinucleus or fragmented nucleus and numerical or sutructural mutations were also found. Furthermore it was observed that total protein amounts …

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Antioxidant Enzymes Activities In Chemically Warfared Samples Ofdociostaurus Maroccanusobtained From An Epidemic Population, Aysun Özkan, Gülgün Gündüz, Battal Çiplak, Kayahan Fişkin Jan 2000

Antioxidant Enzymes Activities In Chemically Warfared Samples Ofdociostaurus Maroccanusobtained From An Epidemic Population, Aysun Özkan, Gülgün Gündüz, Battal Çiplak, Kayahan Fişkin

Turkish Journal of Biology

Antioxidant enzyme activities at first, second, third nymphal stage and adult individuals of nition [O-O-dimethyl-O-(3-methyl-4-nitro-phenyl) phosphorothioate] administered D. maroccanusare investigated. Living specimens where nition had been administered for chemical contention by Agricultural Head Office of Antalya Province in 1996 were taken from epidemic population of Eynif plain (Ibradi, Antalya). Catalase, GSH-reductase, GSH-peroxidase and Se-dependent-GSH-peroxidase activities are assayed spectorofotometrically. The catalase activity did indicate no significant change in any nymphal stage. GSH-reductase activity increased in adult individuals. Se-GSH-peroxidase activity decreased with second nymphal stage and increased with the third one, Whereas GSH-peroxidase activity increased at second nymphal stage of D. maroccanus.

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The Effect Of Some Nutrients Supplementation To Synthetic Compostwith Wheat Straw Before Mycel Inoculation, On Mycelium Growth, Yieldand Early Ripe Of Agaricus Bitorquis(Quél). Sacc, Hasan Hüseyi̇n Doğan, Celaleddi̇n Öztürk, Cengi̇z Akköz Jan 2000

The Effect Of Some Nutrients Supplementation To Synthetic Compostwith Wheat Straw Before Mycel Inoculation, On Mycelium Growth, Yieldand Early Ripe Of Agaricus Bitorquis(Quél). Sacc, Hasan Hüseyi̇n Doğan, Celaleddi̇n Öztürk, Cengi̇z Akköz

Turkish Journal of Biology

The effect of some nutrients added to synthetic compost with wheat straw, on mycelium growth, yield and early ripe of Agaricus bitorquis (Quél.) Sacc. were investigated. The compost was prepared by fermentation and chemical disinfection methods. Corn flour, wheat flour, hen grain, soybean meal and sunflower seed hulls were used as additional nutrients. The experiments were made at the temperatüre 20-22°C and 80-90% relative humidity in the yield rooms. The shortest mycelium growth period (average 14 days) were determined in containing 350 g/10 kg and 450 g/10 kg sunflower seed hulls. The maximum production were taken in the sacks of …

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Effects Of Gibberellic Acid On Male Sterility, Seed Yield And Oil And Fatty Acid Syntheses Of Safflower ( Carthamus Tinctorius L.), Hasan Baydar Jan 2000

Effects Of Gibberellic Acid On Male Sterility, Seed Yield And Oil And Fatty Acid Syntheses Of Safflower ( Carthamus Tinctorius L.), Hasan Baydar

Turkish Journal of Biology

The purpose of this study was to determine the effects of gibberellic acid (GA 3 ) on male and female sterility, seed yield, oil and fatty acid syntheses, growth and development properties in safflower ( Carthamus tinctorius var. Yenice). GA 3 was applied in five different doses at three different stages, and induced male sterility at a rate of up to 93.0%. This finding has important implications for the practical use of GA 3 in hybrid seed production. GA 3 applications significantly decreased the seed yield per plant both in isolation and non-isolation. Although fatty acid syntheses did not change …

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Simple Production And Purification Of Monoclonalantibodies In Serum-Free Medium, Aynur Başalp, Beyazit Çirakoğlu, Engin Bermek Jan 2000

Simple Production And Purification Of Monoclonalantibodies In Serum-Free Medium, Aynur Başalp, Beyazit Çirakoğlu, Engin Bermek

Turkish Journal of Biology

Although serum is a main source of essential nutrients and growth factors, its use creates highly complex and poorly defined media. The use of serum-free media is more efficient than the use of media containing serum especially when the purification and characterization of antibodies are considered. In this study, we developed a serum-free medium system for cultivation of hybrid cells producing monoclonal antibodies specific for Tobacco Mosaic Virus (1F5) and 17\beta-estradiol (10F4) (15D4). Cells were cultivated in a medium with 10 % FCS for three days, and subsequently in serum-free medium for two days. The procedure was repeated once again …

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Analysis Of Functional Domains On Glutamatesynthase, Barbaros Nalbantoğlu Jan 2000

Analysis Of Functional Domains On Glutamatesynthase, Barbaros Nalbantoğlu

Turkish Journal of Biology

Glutamate synthases (GOGAT) were analyzed to identify the functional binding domains of the substrate (glutamine) and cofactors (FMN, NAD(P)H, FAD, [3Fe-4S]1+,0 and [4Fe-4S]2+,1+ clusters and ferredoxin) on this enzyme. The published amino acid sequences of six different NAD(P)H-dependent GOGATs (NAD(P)H-GOGAT) and ten different ferredoxin-dependent GOGATs (Fd-GOGAT) were used for this analysis. The amino acid sequences of these sixteen GOGATs were compared with the amino acid sequences of aminotransferases for glutamine, flavoproteins for FMN, flavoproteins and pyridine-nucleotide-dependent enzymes for FAD and NAD(P)H, iron-sulfur proteins for [3Fe-4S] 1+,0 and [4Fe-4S]2+,1+ clusters and ferredoxin-dependent enzymes for ferredoxin. It was determined that Fd-GOGAT has …

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Hydrophobicities And Electrostatic Behavior Ofdifferent Micro-Organisms, Abbas Yousefi Rad, Hakan Ayhan, Erhan Pi̇şki̇n, Özgül Kisa Jan 2000

Hydrophobicities And Electrostatic Behavior Ofdifferent Micro-Organisms, Abbas Yousefi Rad, Hakan Ayhan, Erhan Pi̇şki̇n, Özgül Kisa

Turkish Journal of Biology

The surface properties of 7 different micro-organisms with their 14 different strains were examined. The contact angles of the micro-organism films were measured by a captive-bubble technique. Surface free energies were calculated from the contact angles. Hydrophobicities were also evaluated by adhesion to p-xylene. The zeta potentials and surface charges of the micro-organisms were measured using a zeta potential analyser system. The contact angles of the gram positive micro-organisms, gram negative micro-organisms and Candida ablicans were in the ranges 48-70°, 43.5-55°, and 69-75° respectively, while the corresponding surface free energies were in the ranges 44.9-60.4 erg.cm -2 , 55.3-61.8 erg.cm …

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Effects Of Various Physiological Stresses Ontranscription Of The Suc2gene In The Yeastsaccharomyces Cerevisiae, Sezai̇ Türkel Jan 2000

Effects Of Various Physiological Stresses Ontranscription Of The Suc2gene In The Yeastsaccharomyces Cerevisiae, Sezai̇ Türkel

Turkish Journal of Biology

Physiological conditions in the growth habitat of yeast cells dramatically changes the gene expression pattern. In this study, it was shown that transcription of the SUC2gene, which encodes the cytoplasmic and secreted enzyme invertase, is modulated according to the environmental conditions in the yeast Saccharomyces cerevisiae. Hyperosmotic stress and oxidative stress repressed the transcription of the SUC2gene up to 50%. However, preconditioning of the yeast cells prevented the negative effects of osmotic stress on SUC2gene transcription. These results clearly show that, apart from the control of invertase activity and its secretion, osmotic stress and oxidative stress also represses transcription of …

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Genomic Imprinting: A Specialized Form Of Generegulation, Fatma Fi̇li̇z Çoşkun Ari Jan 2000

Genomic Imprinting: A Specialized Form Of Generegulation, Fatma Fi̇li̇z Çoşkun Ari

Turkish Journal of Biology

Genomic imprinting is a process resulting in the preferential expression of certain genes depending on whether the genetic material has been inherited from the mother or the father. Many imprinted genes have been identified as having important roles in mammalian development, and the loss of imprints as well as non-imprinted alleles causes a variety of developmental abnormalities and pathological conditions in both mice and humans. In this article, the phenomenon of genomic imprinting, the developmental implications of imprinting and the molecular mechanisms proposed for this process are reviewed.

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Hepatitis C Virus: Genome Organization, Viralproteins And Implications In Disease Pathogenesis, Çağla Eroğlu, Ergün Pinarbaşi Jan 2000

Hepatitis C Virus: Genome Organization, Viralproteins And Implications In Disease Pathogenesis, Çağla Eroğlu, Ergün Pinarbaşi

Turkish Journal of Biology

The hepatitis C virus (HCV) infection is a significant cause of morbidity and mortality worldwide. Infection with HCV becomes chronic in more than 80% of cases and it accounts for 20% of all cases of acute hepatitis. The hepatitis C virus was first identified by the molecular cloning of the virus genome in 1989. It is an enveloped, positive strand RNA virus with a genome size of around 9.5 kilobases. The single-stranded RNA genome of the virus contains a large open reading frame that encodes a large polyprotein of 3,010 to 3,033 amino acids shown to be processed by a …

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Monitoring Of Germin Synthesis By Pre-Absorbedanti-Germin Serum, Mahmut Çalişkan, Andrew C. Cuming Jan 2000

Monitoring Of Germin Synthesis By Pre-Absorbedanti-Germin Serum, Mahmut Çalişkan, Andrew C. Cuming

Turkish Journal of Biology

The transition of a quiescent plant embryo into a vigorously growing embryo revealed some nascent synthesis of gene products, among them germin has been characterized. Germin is a water soluble homopentameric glycoprotein whose synthesis and accumulation appear to be closely related to early wheat embryo development. Germin synthesis was monitored by employing an anti-germin serum which had been pre-adsorbed with wheat extract and optimized in order to decrease nonspecific binding. Germin accumulation was shown to occur in germinating embryos from 16h up to 6 day post-imbibition. Germin as a rare protein in wheat seedlings was detected as a dark band …

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Susceptibility Of Chickpea ( Cicer Arietinuml.)Cultivars To Agrobacterium Tumefaciens(Smith Andtownsend) Conn, Azi̇z Karakaya, Sebahatti̇n Özcan Jan 2000

Susceptibility Of Chickpea ( Cicer Arietinuml.)Cultivars To Agrobacterium Tumefaciens(Smith Andtownsend) Conn, Azi̇z Karakaya, Sebahatti̇n Özcan

Turkish Journal of Biology

Twelve chickpea cultivars grown in Turkey were assessed for susceptibility to wild-type Agrobacterium tumefaciens strains A281 and A136NC. Although all chickpea cultivars showed susceptibility to infection from both A. tumefaciens strains, Diyar-95, Flip 87-8, Ispanyol, Gökçe, Damla-89, and Aziziye-94 had higher frequencies of tumor formation from both strains than the other cultivars tested.

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Freeliving Ciliates Of Pure And Soils Polluted Byconstituents Of Oil Lifting At Apsheron Peninsula, İlham Kh Alekperov Jan 2000

Freeliving Ciliates Of Pure And Soils Polluted Byconstituents Of Oil Lifting At Apsheron Peninsula, İlham Kh Alekperov

Turkish Journal of Biology

The data compiled during five-year-long investigation on the influence of drilling water and crude oil on specific composition, number and structure of the communities of free-living soil ciliates is presented. The vertical distribution of ciliates and their colonizing potential in the sterile soil monoliths placed in clean and polluted soils was studied on the basis of their survival and physiological responses. The changes in certain ciliate species were demonstrated by biotesting of the influence of various concentrations of drillinig water, crude oil and drillinig muds on these ciliates.

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The Effect Of Calcium Concentration Of Water Onchloride Cell Density In Gill Of Brown Trout(Salmo Trutta L.) Larvae, Meti̇n Çalta Jan 2000

The Effect Of Calcium Concentration Of Water Onchloride Cell Density In Gill Of Brown Trout(Salmo Trutta L.) Larvae, Meti̇n Çalta

Turkish Journal of Biology

The effects of the calcium concentration on chloride cell (mitochondria-rich cell) density in the gills of brown trout ( Salmo trutta L.) larvae were studied. For this purpose, animals were divided into 3 groups 2 weeks after hatching and each groups was exposed to different calcium concentrations of water for two weeks. The results showed that the number of chloride cells in gill arch epithelia of larval fish increased with decreased calcium concentration.This increase was statistically significant in the gills of larvae kept in zero-Ca 2+ freshwater (ZCWF) ( P< 0.001 ) and of those kept in low-Ca 2+ freshwater (LCFW) ( P< 0.05) in comparision with the gills of larvae kept in normal freshwater (NFW).

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In Situ Germination Of Pollen Tetrads In Periplocagraceae L. (Periplocaceae), Feruzan Dane Jan 2000

In Situ Germination Of Pollen Tetrads In Periplocagraceae L. (Periplocaceae), Feruzan Dane

Turkish Journal of Biology

The mature anthers in large flower buds of Periploca graceae L. ( Periplocaceae ) were examined cytologically. It was seen that pollen was retained in permanent tetrads. Pollen tetrads were usually observed as isobilateral, rarely as linear. It was also observed that pollen tetrads germinated within the anther loculi. Most of the pollen tetrads were well stained and the germination rate was 90 %. In in situ germinated pollen tetrads, 1-4 pollen tubes were observed. During germination of pollen tetrads, the behavior of the nuclei was normal. At the early stage of pollen tube formation, a vegetative nucleus and two …

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Study Of Interphases Betweensubunits Of Human Serum Albumin By Tritiumlabelling Method, Elimchan S. Dzhafarov Jan 2000

Study Of Interphases Betweensubunits Of Human Serum Albumin By Tritiumlabelling Method, Elimchan S. Dzhafarov

Turkish Journal of Biology

For the purpose of obtaining information about interphases between subunits of human serum albumin (HSA), a new tritium labelling method was adopted. The existence of linear dependence between accessible surface of amino acid residues and their specific radio-activity enabled to obtain information about qualitattive and quantitative amino acid composition of surface layer of protein globule and its large fragments. It is shown that the fragments surface characterized by higher accessibility of hydrophobic amino acid residues such as Ala, Val, Leu, Ile, Pro and Phe. Moreover Lys, Asx and Glx demonstrate high accessibility also. It is supposed that the spatial HSA …

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Pollen Characters And Their Evolutionarysignificance With Special Reference To The Flora Ofkarachi, Anjum Perveen Jan 2000

Pollen Characters And Their Evolutionarysignificance With Special Reference To The Flora Ofkarachi, Anjum Perveen

Turkish Journal of Biology

The pollen morphology of 353 species from Karachi, belonging to 67 families of angiosperms, distributed in 58 dicots and 9 monocots were investigated by scanning electron microscope (S.E.M.) and light microscope (L.M.). Examination of these families revealed great pollen diversity in their qualitative and quantitative characters. However, from a phylogenetic and evolutionary point of view, polarity, symmetry, apertural types and exine sculpturing are the most important characters. In general, dicot pollen is relatively more specialized than that of monocots. Dicotyledons are generally characterized by radially symmetrical, isopolar, colporate, colpate and porate pollen, whereas monocotyledon are usually heteropolar, bilaterally symmetric, boat-shaped, …

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Investigation On The Liver Functions Agriculturel Workers Chronically Exposed To Pesticides, Ülkü Çömelekoğlu, Bi̇rgül Mazmanci, Abdullah Arpaci Jan 2000

Investigation On The Liver Functions Agriculturel Workers Chronically Exposed To Pesticides, Ülkü Çömelekoğlu, Bi̇rgül Mazmanci, Abdullah Arpaci

Turkish Journal of Biology

Blood samples were taken from agricultural workers who had been exposed to pesticides for long periods in Içel and the surrounding agricultural areas (n=150) and levels of AST, ALT, ALP, LDH, total protein, albumin and globulin in serum were determined. The same parameters were measured in 64 persons who are not exposed to pesticides in any way. Study group showed significantly higher levels of AST, ALT, ALP and LDH (p

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Erythrocyte Superoxide Dismutase And Catalase Activities In Agricultureworkers Who Have Been Chronically Exposed To Pesticides, Ülkü Çömelekoğlu, Bi̇rgül Mazmanci, Abdullah Arpaci Jan 2000

Erythrocyte Superoxide Dismutase And Catalase Activities In Agricultureworkers Who Have Been Chronically Exposed To Pesticides, Ülkü Çömelekoğlu, Bi̇rgül Mazmanci, Abdullah Arpaci

Turkish Journal of Biology

Blood samples were taken from farmworkers (n=40) who had been long-term exposed with pesticides (16.52±6.92 years) in Içel and surrounding agricultural areas and measured erythrocyte superoxide dismutase (SOD) and catalase (CAT) activities were measured using spectrophotometric assignation. These antioxidant enzymes were also evaulated in people who had not been exposed to pesticides (n=30). It was observed that erythrocyte SOD levels were significantly higher (p

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