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Enzyme Reactions Using Ureidosuccinate As A Substrate During Pyrimidine Biosynthesis And Degradation In Cl. Oroticum, Penny Amy Aug 1974

Enzyme Reactions Using Ureidosuccinate As A Substrate During Pyrimidine Biosynthesis And Degradation In Cl. Oroticum, Penny Amy

Dissertations and Theses

Cells of Clostridium oroticum, an anaerobic bacterium, were grown on orotate as a carbon and energy source. Ureidosuccinase, an inducible enzyme in the pathway for pyrimidine degradation has been shown to convert ureidosuccinate to aspartate, CO2 and NH3 as reported by Liebenmm and Kornberg (7). Aspartate and CO2 were formed in approximately a 1:1 ratio from ureidosuccinase activity.

Ureidosuccinase was found to be a Mn+2 requiring enzyme with a pH optimum of approximately pH 6.5. Enzyme activity is labile to O2, temperature, pH, dilution and high ionic strength. The optimum conditions for storage …


Infection Of Smallmouth Bass And Goldfish By Two Species Of Saprolegnia, Cheryl A. Mcginley Jul 1974

Infection Of Smallmouth Bass And Goldfish By Two Species Of Saprolegnia, Cheryl A. Mcginley

Dissertations and Theses

This study consisted of several experiments designed to compare the ability of two species of fungi, Saprolegnia ferax and S. parasitica to grow on two species of fish, smallmouth bass (Micropterus dolomieui) and goldfish (Carassius auratus), and to determine the criteria necessary for the development of these infections.

The results indicate that water in the fish tanks must be slightly acid (pH 6), warm (22°C), nonmoving, and that the fish must be wounded in order for fungal infection to occur. Cool water (18°C) and moving water, caused by aeration and filtration, are detrimental to fungal colony formation so that no …


Effects Of The Nerve During The Dedifferentiative Phase Of Limb Regeneration In The Mexican Axolotl, Ambystoma Mexicanum, Roberta Gail Wald Jul 1974

Effects Of The Nerve During The Dedifferentiative Phase Of Limb Regeneration In The Mexican Axolotl, Ambystoma Mexicanum, Roberta Gail Wald

Dissertations and Theses

It is known that nerves are particularly critical during the early or dedifferentiative phase of limb regeneration. During this period in the innervated limb, cells just proximal to the amputation surface dedifferentiate, migrate to the limb tip, and undergo mitosis. These processes give rise to a population of undifferentiated mesenchymatous cells capable of redifferentiating into the missing components of the newly forming regenerate. The consequences of denervation stand in stark contrast to the normal events occurring in the innervated limb, because neither a blastema nor a regenerate forms.

Results from this study indicate that during the early portion of the …


Physiological And Behavior Studies Of Thelepus Crispus And Its Commensal Halosydna Brevisetosa, John B. Morgan Jan 1974

Physiological And Behavior Studies Of Thelepus Crispus And Its Commensal Halosydna Brevisetosa, John B. Morgan

Dissertations and Theses

Chemical, physical and physiological interactions between the marine commensal scaleworm Halosydna brevisetosa Kinberg and its terebellid host, Thelepus crispus Johnson were investigated. In an experiment designed to test for chemical attraction between the host and commensal, Halosydna were unable to identify the arm in a U-tube choice apparatus leading to the host. In 50 trials, 54% of the commensals crawled into the flow of water from their hosts. Other observations showed that Halosydna made contact with the host by random encounter. After contact, commensals followed tentacles down into the host’s tube and took up a characteristic position along the dorsum …


An Investigation Of Infection Mechanisms Of Arceuthobium Campylopodum, Annabella Jaramillo Garcia Jan 1974

An Investigation Of Infection Mechanisms Of Arceuthobium Campylopodum, Annabella Jaramillo Garcia

Dissertations and Theses

Wound periderm is formed by Juniperus occidentalis and Calocedrus decurrens in resistance to infection by the dwarf mistletoe Arceuthobium campylopodum. The pattern of wound periderm formation suggests that chemical as well as mechanical factors are involved. The concentration of hydrolases in the radicular apex of the parasite suggests that they may facilitate the penetration process by which dwarf mistletoes infect their hosts. Emzymatic assistance may also provide a partial explanation for the specificity with which dwarf mistletoes are adapted to given hosts. These resistance responses by the the non-host species were compared with the normal infection process Pinus ponderosa.


Lead Content Of Hair Of Urban And Rural Populations Of Small Animals, Richard Brian Raymond Nov 1973

Lead Content Of Hair Of Urban And Rural Populations Of Small Animals, Richard Brian Raymond

Dissertations and Theses

Hair from small mammals of roadside, urban parkland, wilderness, and antique populations was analyzed for lead by atomic absorption spectrophotometry. Hair from roadside populations had a significantly greater amount of lead than hair from the ether groups. Hair from antique populations did not differ in lead content from that of current populations which are removed from immediate exposure to automotive exhausts.


Characteristics Of Arginase From The Terebellid Polychaete Pista Pacifica Berkeley, Karen Laurel O'Malley Sep 1973

Characteristics Of Arginase From The Terebellid Polychaete Pista Pacifica Berkeley, Karen Laurel O'Malley

Dissertations and Theses

Arginase has been found to occur in the tentacles, gut, and body wall of Pista pacifica Berkeley. Partially purified arginase from the intestine has a molecular weight of 200,000, a Km of about 155 mM, an arginase/canavanase ratio of 22, a pH optimum of 10.5, and a temperature optimum of 60°C. In addition, P. pacifica arginase is competitively inhibited by ornithine but is not inhibited by high arginine concentrations, nor by sulfhydryl reagents. The enzyme is not stimulated by exogenous manganese and breaks down into an active subunit under harsh treatment. The subunit has a Km of about 118 mM …


A Test Of The Simple Recessive Hypothesis For The Inability To Taste Phenyl-Thio-Urea: A Family Study, Susan I. Wolf Aug 1973

A Test Of The Simple Recessive Hypothesis For The Inability To Taste Phenyl-Thio-Urea: A Family Study, Susan I. Wolf

Dissertations and Theses

This thesis is a report on the analysis of family data gathered to test the simple recessive hypothesis for the inability to taste phenyl-thio-urea (P.T.C.). The simple recessive hypothesis states that the inability of a minority of persons to taste high concentrations of P.T.C. is due to the action of an autosomal recessive gene in the homozygous condition.


Growth Of Selenastrum Capricornutum Printz In Natural Waters Treated With Copper Sulfate, Gerald Eugene Schulz Aug 1973

Growth Of Selenastrum Capricornutum Printz In Natural Waters Treated With Copper Sulfate, Gerald Eugene Schulz

Dissertations and Theses

The green alga, Selenastrum capricornutum Printz, was used in an algal bioassay to determine the toxic properties of copper in various natural lake waters of Oregon. Lake water was collected and brought back to the laboratory where it was treated with various copper concentrations and inoculated with a cell suspension of the test alga. Growth of the alga was determined by direct cell counts. The copper ion activity, pH, and absorbance of the test cultures were also determined. The growth of the alga was ·found to depend upon the water tested and also upon the copper concentration used.


Possible Avian Influences In The Distribution Of Dwarf Mistletoe, Paul James Zilka Jul 1973

Possible Avian Influences In The Distribution Of Dwarf Mistletoe, Paul James Zilka

Dissertations and Theses

The goal of this investigation was to determine the potential of birds as vectors for the movement of dwarf mistletoe seeds and the means by which such movement could occur. Birds would greatly speed the rate at which these parasites move horizontally or vertically through the forest. Five areas in Oregon, heavily infected by six species of Arceuthobium were studied. Observations of avian behavior point to 13 species whose general behavior make them potential vectors in the distribution of these parasites. More specifically, the roosting and subsequent bathing behavior of most forest birds proves a very important means of potential …


Purification And Characterization Of Dihydroorotase From Clostridium Oroticum, A Zinc-Containing Metalloenzyme, William Edward Balch Jun 1973

Purification And Characterization Of Dihydroorotase From Clostridium Oroticum, A Zinc-Containing Metalloenzyme, William Edward Balch

Dissertations and Theses

Dihydroorotase (4,5-L-dihydro-orotate amidohydrolase, EC 3.5.2.3) which catalyzes the reversible cyclization of N-carbamyl-1-aspartate toL-dihydro-orotate has been purified from orotate-grown Clostridium oroticum by a combination of streptomycin sulfate fractionation, DEAE-Sephadex chromatography, and hydroxylapatite chromatograpy. The enzyme has been shown to be omogeneous when subjected to polyacrylamide gel electrophoresis. Thin-layer gel chromatography with Sephadex G-200 indicated the enzyme to have a molecular weight of 110,000 ± 10,000. Sodium dodecyl sulfate gel electrophoresis using two different buffer systems indicate the enzyme to be composed of two identical subunits with a molecular weight of 56,000 ± 5300. Dihydroorotase has been shown to be a zinc-containing …


Agonistic Behavior And Dominance In Townsend's Chipmunks (Eutamias Townsendii), Paul Evan Sherman May 1973

Agonistic Behavior And Dominance In Townsend's Chipmunks (Eutamias Townsendii), Paul Evan Sherman

Dissertations and Theses

Agonistic behavior and dominance are described for captive Townsend's chipmunks (Eutamias townsendii). A total of 10,739 encounters was recorded; 6441 (59.9%) were agonistic. Chases (58.5%) and displacements (30.8%) were the predominant agonistic behaviors; threats (6.8%) and fights (4.l%) were relatively rare.

Stable, non-triangular hierarchies were rapidly established in 11 of the 12 groups of chipmunks observed; the presence of individuals of equal rank in some groups precluded strict linearity. Dominance positions did not change within a group, but reversals in rank and changes from equal to dominant-subordinate relationships occurred when the membership of groups was changed. One hierarchy …


Photosynthesis And Respiration Of Arceuthobium Tsugense, James Roger Miller Jan 1973

Photosynthesis And Respiration Of Arceuthobium Tsugense, James Roger Miller

Dissertations and Theses

Dark respiration rates of the aerial shoots of Arceuthobium tsugense, obtained by manometric and IRGA techniques, show production of C02to range between 155-300 µl CO2 g-1h-1 with evidence of seasonal variation. Experiments with 14C02 indicate that the aerial shoots are capable of some photosynthetic CO2 fixation, with 10-15% of the available 14C incorporated by the plant tissue in one hour.The portions of the o aerial shoots which are most active in C02 fixation are the young terminal regions. Biochemical characterization of the products of photosynthesis reveals that 80-90% of …


A Survey For Leucocytozoon Simondi Mathis And Leger (1910) In Canada Geese Of The Malheur Wildlife Refuge, John Val Snively Jan 1973

A Survey For Leucocytozoon Simondi Mathis And Leger (1910) In Canada Geese Of The Malheur Wildlife Refuge, John Val Snively

Dissertations and Theses

Blood smears of blood collected in 1971 and 1972 from 291 Canada geese at Malheur National Wildlife Refuge were examined to determine the incidence of the avian malarial parasite, Leucocytozoon simondi. No parasites were found. Absence of blood parasites suggests that birds using migration routes to the north and northeast of Malheur are free of the disease.

The Leucocytozoon infections known in California waterfowl may be attributable to sources within the flyway east or northeast of California, to infected birds crossing over from other flyways, or abnormal conditions in the molting grounds of sub-adult and non-nesting birds where major flyways …


Some Aspects Of The Water Economics Of Townsend's Chipmunks, Ali Mokhtar Rahima Jan 1973

Some Aspects Of The Water Economics Of Townsend's Chipmunks, Ali Mokhtar Rahima

Dissertations and Theses

Water consumption, and weight loss in response to water deprivation and saline water consumption, were studied in the Eutamias townsendii townsendii from Portland, Multnomah County, Oregon. These chipmunks occupy moist Pacific Northwest forests. The results of these studies suggest that Townsend's chipmunks are dependent on sources of drinking water, at least for normal above ground activity, that their tolerance for water deprivation is comparatively low, and that they are unable to obtain a net gain of water by drinking 0.2 M sodium chloride solutions. Chipmunks cannot drink 0.4 M NaCl solution and survive for more than a few days. Metabolic …


Life Cycle, Additions To Biology, And New Hosts Of Apophallus Donicus (Trematoda: Heterophyidae) In Oregon, Delbert Raymond Niemi Jan 1973

Life Cycle, Additions To Biology, And New Hosts Of Apophallus Donicus (Trematoda: Heterophyidae) In Oregon, Delbert Raymond Niemi

Dissertations and Theses

Apophallus donicus is examined, its life cycle is described, and certain additions are made to its biology. It is thought, but not proven, that eggs are eaten by the first.intermediate host, the local stream snail FluI menicola virens, and the miracidia escape internally. Mother and daughter rediae stages result, the later producing cercariae which are shed into the water. After burrowing just beneath the skin in suckers (Catostomus macrocheilus Girard), rainbow trout (Salmo 9airdneri Richardson), coho salmon (Oncorhynchus kisutch (Walbaum) squawfish (Ptychocheilus oregonensis Richardson), blackside dace (Rhinichthys osculus nubilus (Girard), redside shiners (Richardsonius balteatus balteatus (Richardson),and possibly other fish, the …


Factors Affecting The Population Of Raptorial Birds On Sauvie Island, Oregon, Jeffry Gottfried Dec 1972

Factors Affecting The Population Of Raptorial Birds On Sauvie Island, Oregon, Jeffry Gottfried

Dissertations and Theses

This study is an analysis of the various factors affecting the population of raptorial birds on Sauvie Island, Oregon. A census of diurnal and nocturnal raptors was carried out along with an analysis of food habits. Once the major prey species were determined they were censused, and the effects of the land management practices on their numbers was investigated. In addition, 100 randomly selected nest boxes were sampled so as to determine the extent to which raptors were making use of them. Red-tailed hawk and Great Horned Owl nests were located.

It was found that four diurnal raptors and three …


Euryhelmis Cotti N. Sp. (Trematoda: Heterophyidae) With Observations On Its Life Cycle, Michael Joseph Simon Mar 1972

Euryhelmis Cotti N. Sp. (Trematoda: Heterophyidae) With Observations On Its Life Cycle, Michael Joseph Simon

Dissertations and Theses

Fish of the genus Cottus were found infected with heterophyid metacercariae. Laboratory animals were infected with the metacercariae, and adult heterophid trematodes were recovered. These flukes were found to represent an undescribed species of the genus Euryhelmis. Various streams in the Willamette Valley and coastal areas were sampled for infected Cottus sp. Snails of the genera Oxytrema and Fluminicola were collected. Several possible definitive hosts were examined. A partial review of the subfamily Apophallinae and a complete review of the genus Euryhelmis are presented. Euryhelmis cotti n. sp. is placed in the subfamily Apophallinae, and its life cycle …


Polychlorinated Biphenyls: Uptake By Daphnia And Residues In Crayfish From The Willamette River, John J. Salmon Jan 1972

Polychlorinated Biphenyls: Uptake By Daphnia And Residues In Crayfish From The Willamette River, John J. Salmon

Dissertations and Theses

Polychlorinated Biphenyls (PCB's) are organochlorine molecules which find various industrial and product applications. PCB's are of concern to biologists because they are toxic substances which have become global contaminants. They are also of concern to biologists and analytical chemists because they interfere with the determination of some organochlorine pesticide residues. PCB's were discovered to be environmental contaminants after they showed up as unidentified peaks in pesticide analysis using gas-liquid chromatography with an electron capture detector (GLC-EC).

In the present experiment standard GLC-EC techniques were used to assay PCB's in Daphnia experimentally contaminated in the laboratory and in crayfish from the …


The Life Cycle Of Lissorchis Heterorchis, Macy And Krygier (1969), Brendan P. H. Onyejekwe Jan 1972

The Life Cycle Of Lissorchis Heterorchis, Macy And Krygier (1969), Brendan P. H. Onyejekwe

Dissertations and Theses

Many Flumenicola virens (Lea) collected from Crystal Springs Creek and Tualatin River, Portland, Oregon, were found to shed large numbers of a species of microcercous cercariae containing refractile granules. They resembled the cercariae of Triganodistomum mutabile (=Lissorchis mutabile Cort, 1918 as described by Wallace (1939), and subsequent experiments proved that they were the larval stages of what was described by Macy and Krygier (1969), as Lissorchis heterorchis. Encystment of these cercariae was induced experimentally in uninfected adult brown planarians collected partly from Crystal Springs Creek and partly from Carolina Biological Research Station in Gladstone, Portland, Oregon. Adult flukes were obtained …


A Taxonomic Study Of Two Nominal Subspecies Of Pikas (Ochotona Princeps) In The Cascade Mountains Of Oregon, Richard M. Coots Jan 1972

A Taxonomic Study Of Two Nominal Subspecies Of Pikas (Ochotona Princeps) In The Cascade Mountains Of Oregon, Richard M. Coots

Dissertations and Theses

Pikas from four colonies in the Cascade Mountains of Oregon were examined. Two colonies were chosen from within the geographical distribution of two nominal subspecies. A discriminate analysis of morphological measurements taken from the specimens showed that each colony could be distinguished from each other. Each colony studied showed more intra-colony similarity than inter-colony similarity regardless of distance separating the colonies or subspecies designations. The results indicate that the validity of subspecies designations for this species can be questioned.


Mutual Exclusion Between Salmonberry And Douglas-Fir In The Coast Range Of Oregon, Kenneth Ray Still Jan 1972

Mutual Exclusion Between Salmonberry And Douglas-Fir In The Coast Range Of Oregon, Kenneth Ray Still

Dissertations and Theses

One serious problem faced by the forest industry in the Pacific Northwest is poor regeneration of commercial trees on land which is harvested and subsequently dominated by brush species. In Coastal Oregon, salmonberry is one of these brush species. Detailed investigations of field sites indicate that light intensity in the brush stands was low but sufficient for germination and early growth of Douglas-fir seedlings and soil moisture percentages and nutrient levels were high enough to support early Douglas-fir growth. Laboratory tests demonstrated the presence of leachable phytotoxins in the leaves of salmonberry. The hypothesis resulting from this study is that …


Repression Of Β-Galactosidase Synthesis In Escherichia Coli By Salicylates, Joan Carlyn Olson Jan 1972

Repression Of Β-Galactosidase Synthesis In Escherichia Coli By Salicylates, Joan Carlyn Olson

Dissertations and Theses

Salicylic acid, and to a lesser extent aspirin, have been shown to repress β-galactosidase synthesis in Escherichia coli. The repression is not due to decreased inducer uptake, nor does it result from competition with inducer for repressor. Dinitrophenol does not exert similar effects on β-galactosidase synthesis. Cyclic adenosine 31, 51-monophosphate partially relieves the repression. The extent or the relief by cyclic adenosine monophosphate seems to depend on the concentration of salicylic acid. This indicates there may be direct interaction between the actions of cyclic adenosine monophosphate and salicylic acid in E. coli cells.


A Taxonomic Study Of The Marine Algae Of Netarts Bay, Oregon, Charles Jerome Kunert Jan 1972

A Taxonomic Study Of The Marine Algae Of Netarts Bay, Oregon, Charles Jerome Kunert

Dissertations and Theses

Gathering taxonomic data is fundamental to any biological or ecological research. It was the intent of this paper to increase the storehouse of taxonomic information by studying the marine algae of one section of the Oregon coastline. Netarts Bay was chosen because of its accessibility and generally primitive nature. It is in an area of Oregon largely untouched by phycologists and so offered an opportunity for original research.

Techniques of collecting and preserving specimens were kept as simple as possible, thus allowing a proportionately greater amount of the available time to be spent in the classification of the organisms. The …


The Environmental Crisis: The Effects Of Ecology Courses On High School Students, Carol C. Fletcher Dec 1971

The Environmental Crisis: The Effects Of Ecology Courses On High School Students, Carol C. Fletcher

Dissertations and Theses

It is a basic premise of this thesis that an environmental crisis exists in the world today and has been worsening at least since World War II. The crisis is evident in the population explosion, the deteriorating air and water quality, and the depletion of our natural resources. With the feeling that all persons must become aware, concerned, and involved with the environmental crisis if the trend is to be reversed, this study is concerned with one segment of the population – high school students.

Sociologists, and especially human ecologists, have not been concerned professionally with the environmental crisis, but …


Vocalizations Of The Townsend Chipmunk (Eutamias Townsendii), Greig Michael Warner Sep 1971

Vocalizations Of The Townsend Chipmunk (Eutamias Townsendii), Greig Michael Warner

Dissertations and Theses

This study describes and analyzes the vocalizations of the Townsend chipmunk (Eutamias townsendii) in Oregon. Tape recordings of calls were collected primarily from Forest Park in Portland (Oregon) during 1970 and 1971, and sonograms of these recordings were produced. Findings were compared with those of Brand (1970) who investigated E. townsendii vocalizations in California. The prominent calls in the vocal repertoire of townsendii are the quist, the quirt, and the chipper. These calls all appear to be warning calls. The quist note is a a chevron-shaped (A) figure representing a sound which begins at a low frequency (1-2 KC), sharply …


Behavioral Changes Due To Overpopulation In Mice, James Robert Hammock Jul 1971

Behavioral Changes Due To Overpopulation In Mice, James Robert Hammock

Dissertations and Theses

Previous research has found that if a population were allowed to exceed a comfortable density level, then many catastrophic events occurred such as increased mortality among the young, cannibalism, homosexuality, and lack of maternal functions. The most influential researcher in this area is Calhoun (1962), after whose experimental design a pilot study was fashioned to replicate his results. The results of this pilot study inspired a more detailed research project of which this thesis is an account.

Forty-eight albino mice of the Swiss Webster strain were divided into three groups of sixteen each. Each group consisted of ten females and …


Effects Of Insulin, Sodium And D-Glucose On Amino Acid Absorption In The Intestine Of Rats, Andre-Gerard Craan Jun 1971

Effects Of Insulin, Sodium And D-Glucose On Amino Acid Absorption In The Intestine Of Rats, Andre-Gerard Craan

Dissertations and Theses

Amino acid absorption across rat intestine in vitro was inhibited or stimulated by insulin depending on the hormone serosal concentration.

The absence of sodium ions from the incubating solution resulted in a significant decrease of L-alanine absorption. However, L-alanine was enhanced in a sodium-free medium by the addition of insulin on the serosal side of the intestine.

A sizable decrease in L-alanine and L-lysine absorption was produced by introduction of D-glucose (0.2 % and 2 %) in the Krebs-Ringer's incubating buffer. Nevertheless, the presence of D-glucose did not prevent the stimulatory effect of insulin on amino acid absorption.


The Effect Of Antibiotics On Thermophilic Blue-Green Algae, Erleen Blanche Christenson May 1971

The Effect Of Antibiotics On Thermophilic Blue-Green Algae, Erleen Blanche Christenson

Dissertations and Theses

The nature of the action of penicillin on the cell walls of bacteria is reviewed. The composition of bacterial cell walls is compared to cell walls of blue-green algae.

The test organisms used were thermophilic: Anacystis nidulans grew optimally at 35⁰C, whereas Synechococcus lividus grew best at 45⁰ C. Growth was recorded by reading optical densities.

Cells of these two thermophilic blue-green algae were treated with varying dosages of penicillin and streptomycin. Penicillin inhibited growth of Anacystis nidulans and Synechococcus lividus in concentrations of 3.0 µg/ml and 0.03 µg/ml respectively. However, when 0.3 µg/ml of penicillin was added to Anacystis …


Lactic Dehydrogenase Isozyme Isolation By Disc Electrophoresis In Eight Species Of Fringillid Birds, Michael Edwin Darling Jan 1971

Lactic Dehydrogenase Isozyme Isolation By Disc Electrophoresis In Eight Species Of Fringillid Birds, Michael Edwin Darling

Dissertations and Theses

Disc electrophoresis of tissue homogenates from eight species of fringillid birds showed five forms of lactic dehydrogenase. The relative amounts of isozymes were characteristic for each species. This paper classifies some members of the families Fringillidae and Carduelidae in terms of lactic dehydrogenase isozymes and compares the results to other methods of classification.