Biology Commons^™

Effect Of Ethanol On Thermoregulation In The Goldfish Carassius Auratus, Candace Sharon O'Connor

Dissertations and Theses

In an attempt to elucidate the mechanism by which ethanol affects vertebrate thermoregulation, the effect of ethanol on temperature selection was studied in the goldfish, Carassius auratus. Ethanol was administered to 10 to 15 g fish by mixing it in the water of a temperature gradient. The dose response curve was very steep between 0.5% (v/v) ethanol (no response) and 0.7% (significant lowering of selected temperature in treated fish). Fish were exposed to concentrations of ethanol as high as 1.7%, at which concentration most experimental fish lost their ability to swim upright in the water. At concentrations higher than …

The Effect Of Salinity On Habitat Selection Of Two Oregon Chiton Species (Katharina Tunicata And Mopalia Hindsii), David Carl Rostal

Dissertations and Theses

Adult specimens of Katharina tunicata (mean weight = 10.23 grams) and Mopalia hindsii (mean weight = 10.90 grams) were tested for osmotic stress tolerance and oxygen consumption rates in a series of salinities (120%, 100%, 80%, 60%, and 40% seawater) at 11°C and 16L:8D photoperiod. K. tunicata and M. hindsii displayed similar trends in percent body weight variation and volume regulatory responses to osmotic stress. However, K. tunicata experienced a significantly higher percent body weight increase than did M. hindsii in response to hypo-osmotic conditions (80%, 60%, and 40% seawater). The mean rates of oxygen consumption per salinity for the …

Nitrogen Limitation Of Phytoplankton Growth In An Oligotrophic Lake, Michael Patrick Mulvey

Dissertations and Theses

Blue Lake, Jefferson County, Oregon, has high summer surface phosphorus concentrations (ca. 30 ug/l) yet is oligotrophic (summer Secchi depth is 11 to 16 meters). Nutrient enrichment experiments done with 1000 1 polyethylene enclosures indicate nitrate limitation of phytoplankton growth. Basin morphology may be an important factor in nutrient cycling in this lake. The lake has a maximum depth of 95.7 meters with an average depth of 42.7 meters. The lake basin has steep sides with only 4% of the lake bottom less than 3.3 meters deep. of recent volcanic origin.

In contrast, Suttle Lake, which is immediately downstream from …

Morphological Aspects Of Seedling Establishment In Four Temperate Region Phorandendron Spp., Beverlee M. Ruhland

Dissertations and Theses

Four species of Phoradendron were examined for seedling morphology: P. bolleanum subsp. densum (on Juniperus), P. californicum (on Prosopis), P. juniperinum subsp. juniperinum (on Juniperus, P. villosum subsp. villosum (on Quercus). The main species used in the study was P. juniperinum, using the other species for comparison. The initial shoot(s) of P. juniperinum may develop from the epicotyl of the developing seedling, from adventitious buds which arise from a cushion of tissue, termed the haustorial cushion, formed beneath the holdfast, or from both positions. When shoots arise only from adventitious buds the original seedling remains attached in a lateral position, …

The Contribution Of The Lymph Hearts In Compensation For Acute Hypovolemic Stress In The Toad Bufo Marinus, Mark Baustian

Dissertations and Theses

Currently published data on the role of the lymphatic system in amphibians are inadequate and contradictory. Estimates of the rate of formation of lymph and the role of the lymph hearts in returning this fluid to the circulation are not based on actual volume determinations but rather estimates derived from changes in hematocrit using published values of plasma and blood volume. The lymph hearts are known to be vital to the maintenance of normal fluid compartment physiology and to increase their rate of activity during episodes of hypovolemic stress. Yet, significant redistribution of body fluids following hemorrage appears to occur …

Characterization Of A New Freshwater Methanogen, Methanogenium Wolfei Sp. Nov., Theodore B. Moore

Dissertations and Theses

A recently isolated freshwater methanogenium species, Methanogenium wolfei, is characterized. Cells were irregular cocci, measuring 1.5 to 2.0 micrometers in diameter. No motility was observed, but 1 to 2 flagella per cell were observed after staining with Gray's Flagella Stain. Colonies formed by this species were small, shiny, and green-brown in color. Formate or hydrogen plus carbon dioxide served as substrates for growth. The optimal temperature for growth was found to be 45 degrees centigrade with minimal growth below 30 degrees centigrade and above 55 degrees centigrade. The optimal pH for growth was determined to be 6.8. Optimal growth was …

Aspects Of Cardiovascular Oxygen Transport In Vertebrates, Michael Scott Hedrick

Dissertations and Theses

The hematological and rheological characteristics of blood from a number of vertebrates was compared to assess possible species differences in blood viscosity that may influence cardiovascular oxygen transport. Nucleated red blood cells (RBCs) were more viscous (measured by cone-plate viscometry) in comparison with enucleate (mammalian) RBCs at hematocrits greater than 40% when measured at equivalent temperatures. The lower viscosity of enucleate RBCs is attributed to an enhanced deformability of enucleate cells in comparison to nucleated cells.

The Significance Of Hypovolemia In Dehydrational Death In Anurans, Peter Blair Kimmel

Dissertations and Theses

The importance of hypovolemia in dehydrational death was assessed in two anuran species. Xenopus laeyis, a species which experiences a significant reduction in circulating plasma volume with dehydration, was used to evaluate the role of sympathetic reflex compensation in hypovolemia. Adrenergic blockade with propranolol or phenoxybenzamine produced no significant reduction in dehydration tolerance in this species, although β-blockade with propranolol appeared to have a minor effect. The role of hypovolemic shock in the terminal circulatory collapse that precedes death in dehydrating anurans was investigated in the toad, Bufo marinus. The activity of lysosomal proteinases (cathepsins) was used as an indicator …

The Role Of Copper In The Apparent Aluminum Toxicity Of Aquatic Systems, Kirk Thomas O'Reilly

Dissertations and Theses

The effect of variations in aluminum and copper concentrations on the growth rate and enzyme activity of the green alga Scenedesmus quadricauda was investigated. The goal was to determine which chemical species control the biological parameters. The computer program MINEQL (Westal et al 1976) was used to estimate chemical speciation. In the prevalence of both metals, algal growth rate and alkaline phosphatase activity could be correlated to cupric ion activity. The activity of isolated bacterial alkaline phosphatase was found to be a function of both total copper concentration and cupric ion activity. A model was developed to predicted the effects …

Partial Purification And Characterization Of F₄₂₀-Dependent Nadp Reductase From Methanobrevibacter Smithii Strain De1, Scott D. Sheridan

Dissertations and Theses

The F₄₂₀-dependent NADP reductase of Methanobrevibacter smithii has been partially purified employing a combination of affinity chromatography with Blue Sepharose (Cl-6B) and molecular sieve chromatography with Sephacryl S-200, The enzyme, which requires reduced F₄₂₀ as an electron donor, has been purified over 145 fold with a recovery of 6%. A molecular weight of 120,00 for the native enzyme was determined by Sephacryl S-200 chromatography. A subunit molecular weight of 28,200 was determined by SDS-PAGE, indicating that the native enzyme is a tetramer. The optimal temperature for enzymatic activity was found to be 45°C, with a pH optimum …

The Analysis And Use Of Methodologies For The Study Of The Diets Of Long-Eared Owls From Three Environments In North Central Oregon, John M. Barss

Dissertations and Theses

Part I of this study presents a procedure for standardization of pellet analysis methodologies which improves estimation of prey biomass and determines the number of pellets needed to estimate prey diversity indices. The procedure was developed to provide a simple, easily replicated methodology for the study of pellets which also retains maximal data recorded from pellet analysis. A sample size of ten Long-eared Owl pellets was found adequate to calculate diversity indices with no significant loss of accuracy when compared to total pellets recovered from beneath a roosting site. Analysis of the total sample of pellets from a specific roost …

A Phylokaryotypic Evaluation Of The Genus Tursiops (Family Delphinidae), Melissa Kay Estes

Dissertations and Theses

In an attempt to correlate genetic data with possible species delineation, this study investigates the presence of chromosomal variants between the North Atlantic bottle nose dolphin, Tursiops truncatus, and the North Pacific bottle nose dolphin, T. gilli. Blood samples were obtained from oceanaria in the United States. Location of capture was correlated with karyotype to compare chromosome morphology with geographic range.

Effects Of Dehydration On Hemoglobin Oxygen Affinity And Blood Cell Volume In Two Anurans, Andrew Christopher Zygmunt

Dissertations and Theses

Two aspects of possible adaptation in cardiovascular performance caused by increased plasma electrolytes were examined. Cells in anisotonic plasma may either act as osmometers or volume regulate. Blood flow rate is dependent upon cell viscosity, which in turn is a consequence of cell volume and membrane deform-ability. Cell volume changes which increase membrane deform-ability will thus potentially extend the limits of dehydration tolerance. It was found in R. catesbeiana and B. marinus that red blood cell is maintain constant volume during dehydration. Cells in vitro initially lose water, but then sodium, potassium and water move into the cell. Cell viscosity …

Effects Of Intraperitoneal And Intracerebral Injections Of Triiodothyronine On Temperature Selection In Fish, Dennis A. Grahn

Dissertations and Theses

Goldfish (Carassius auratus) of 15-28g were maintained at 23 C and subsequently were intraperitoneally injected with saline (controls) and varying doses of Triiodothyronine (T₃). Following the injection, the fish were placed in a thermal gradient and temperature selection and activity monitored for 30 min. There was no- significant difference between the responses of the experimental fish to the 2 different doses of T₃. However, there was a significant difference in response between the experimental and control groups (P < 0.001). The decreased temperature selection occurred early in the test runs, while the increased activity began later. Larger goldfish (175-205g) received 0.5 μl intracerebral injections of 1.5-3.0 ng T₃ in the anterior brainstem via an indwelling cannula injection system. These fish responded to the injections by …

The Combined Effect Of Cu And Zn On Selenastrum Capricornutum, Helmer Colonia-Roque

Dissertations and Theses

It has been demonstrated that the toxicity of heavy metals depends on their chemical speciation and can be related to their free ion activities, rather than the total metal concentrations. The objective of this study was to determine the effect of combined free ions of zinc and copper on the toxicity to the green alga Selenastrum capricornutum. This alga was grown in a defined medium, under controlled laboratory conditions, with a varying range of zinc and copper concentrations. The growth rate of the alga was inhibited at pZn = 5.93 or at pCu = 7.24. The results suggest that …

Nest Success And Nesting Habits Of Eastern Kingbirds And Other Flycatchers, Michael T. Murphy

Biology Faculty Publications and Presentations

Patterns of nest placement and its relationship to nest success in the Eastern Kingbird (Tyrannus tyrannus) were studied in populations breeding in New York and Kansas. Data were augmented with information on nest placement in other open-nesting tyrannids in order to examine the hypothesis that these flycatchers place their nests chiefly so as to conceal them from predators. Nesting success was significantly greater in New York than in Kansas but was relatively high in both populations, as is apparently true of North American breeding flycatchers in general. Geographic variation in nest placement in the Eastern Kingbird was relatively small and …

Clutch Size In The Eastern Kingbird: Factors Affecting Nestling Survival, Michael T. Murphy

Biology Faculty Publications and Presentations

Observational and experimental procedures were used to evaluate the potential importance of brood size and weather on the evolution of clutch size in the Eastern Kingbird. Modal clutch size was three eggs, yet broods of four were most productive. Nestling size varied inversely with brood size, so that "nestling quality" was lower in broods of four than in broods of three. Asymptotic weight of nestlings in broods of three was directly and significantly correlated with ambient air temperature, followed by hatch order. Because larger broods were being fed during a period of relatively cool and wet weather, the effects of …

Breeding Success And Nest Site Characteristics Of The Western Bluebird On Parrett Mountain, Marcia Diane Sims

Dissertations and Theses

The lack of suitable nest sites may be a limiting factor for Western Bluebird populations inhabiting the upper Willamette Valley. Nest box trails have been established on the hills surrounding the Portland metropolitan area. Since their placement, approximately 25% of the boxes available have been used by Western Bluebirds as nest cavities. This study was undertaken to identify factors which might determine the selection of a nest box by Western Bluebirds and the subsequent nest success or failure.

The breeding biology of Western Bluebirds using the nest box trail located on Parrett Mountain, Oregon in 1979 was investigated. Breeding season, …

Serial Cardiovascular Adaptations During Pregnancy, Mark Vincent Hart

Dissertations and Theses

Maternal cardiovascular adaptations appear to be essential in order to supply extra circulation to both the developing fetus and maternal system during a successful pregnancy. Since inadequate cardiovascular adjustments may produce abortions or maternal morbidity, the characterization of maternal cardiovascular changes during pregnancy and the elaboration of the underlying mechanism for these changes are essential to the understanding of how the heart enlarges during pregnancy and what significance this enlargement might have. To provide needed information regarding this time course and extent of maternal cardiac enlargement and the hormonal and hemodynamic changes which may be responsible for these changes, the …

The Absence Of Extrachromosomal Dna In Methanogenic Bacteria, Nancy Ann Kurkinen

Dissertations and Theses

Five species of methanogenic bacteria were analyzed for the presence of plasmid DNA. Several procedures for the detection and isolation of covalently closed circular plasmid DNA were modified for use with the methanogens.

The Effect Of Dwarf Mistletoe (Arceuthobium Americanum) Upon A Portion Of The Carbon Budget Of Lodgepole Pine (Pinus Contorta), Nancy Ellen Broshot

Dissertations and Theses

Arceuthobium americanum is a vascular plant which is parasitic upon Pinus contorta var. murrayana. Its documented effects include reductions in host growth, vigor and wood quality. The specific physiological changes that occur in the host are, for the most part, unknown.

In an attempt to understand the manner in which the mistletoe alters its host's carbon budget, a model is proposed which states that the host plant has priorities for carbon allocation. The model proposes that the parasite will access the host's carbon initially in terms of carbon intended for storage, next, in terms of carbon intended for growth, …

Temporal And Phenomenological Aspects Of Social Behavior In Captive Wolves (Canis Lupus L.), Paul C. Paquet

Dissertations and Theses

Although cooperative behavior is generally acknowledged to occur among wolves, there is a lack of systematically collected data confirming the extent of development. The objectives of this study were to collect long-term, detailed observations documenting the role of social structure, seasonal influences, and individual participation in wolf pack cooperative activities. Individual cooperative strategies were associated with age, sex, and social positions and critically compared with results of similar studies. Emphasis was placed on quantifying group and dyadic relationships, focusing on reproductive strategies and dominance structure. Additional data were collected on denning behavior, maternal care behavior, scent marking, and spontaneous individual …

Cadmium And Zinc Levels In The Hair Of Smokers And Nonsmokers, Neal R. Simonsen

Dissertations and Theses

To determine the relationship of tobacco and marijuana smoking to levels of cadmium and zinc manifested in hair samples, a study was conducted at Portland State University using atomic absorption spectrophotometry. 97 adult student volunteers participated in the main study.

A Genetic And Physiological Study Of An Arsenite Resistant, Uncoupled Mutant Of Escherichia Coli, Daniel Gordon Smiley

Dissertations and Theses

Chromosomally determined arsenate resistance in Escherichia coli is well characterized. Little, however, is known about chromosomally determined arsenite resistance in E. coli. Accordingly, spontaneous arsenite resistant mutants were selected in a plasmid free strain of E. coli. One mutant strain was analyzed in detail, genetically and physiologically. The mutation confering arsenite resistance was shown to be a single gene mutation. Genetic mapping studies using conjugation and transduction showed that the mutation was closely linked to the ilv region of the E. coli map.

Physiological studies of this mutant showed that it shared characteristics common to those of mutants …

Characterization Of Gram-Positive Bacterial Isolates From Burn Victims, Trisha A. Hannan

Dissertations and Theses

Streptococcus and Staphylococcus were collected from patients hospitalized at the Oregon Burn Center, Emanuel Hospital, Portland, Oregon, between October 27, 1980 and January 1, 1981. Forty-five isolates of Staphylococcus and twenty-one isolates of Streptococcus, Lancefield Group D, were included in the investigation.

The objectives of the investigation were: (i) to identify to the species level all isolates, (ii) to determine their susceptibility to antimicrobial agents, (iii) to test the organisms. over time for increasing resistance to silver, (iv) to determine, if present, a bacterium harbored within the burn unit (nosocomial bacterium), and (v) to determine any recognizable pattern of successive …

Variation In Branch Growth Characteristics Of Pinus Contorta Infected With Arceuthobium Americanum, Lynn Anne Larsen

Dissertations and Theses

Arceuthobium americanum is a flowering plant which parasitizes Pinus contorta (Lodgepole pine). This study examined branch performance of P. contorta infected to varying degrees with A. americanum.

Plasmid-Mediated Resistance To Arsenite And Arsenate In Escherichia Coli, Thomas Patrick Trezona

Dissertations and Theses

Bacterial strains resistant to arsenite, arsenate (or both) are readily isolated from nature. The resistance, in many cases, can be shown to be determined by conjugal plasmids. The mechanisms by which these plasmids confer resistance to arsenic compounds are entirely unknown. This study was undertaken to shed light on some of the physiological and genetic aspects of this resistance using plasmid-bearing strains of Escherichia coli which are highly resistant to both arsenite and arsenate. Most studies were carried out using E. coli J53 (R773) or the plasmid-free strain J53.