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The Fern Prothallium As An Experimental Object For Morphogenetic Studies, Dorothy Anita Douglas May 1955

The Fern Prothallium As An Experimental Object For Morphogenetic Studies, Dorothy Anita Douglas

Theses & Honors Papers

No abstract provided.


A Cytological Study Of The Induced Octoploid Of An Agropyron-Hordeum Hybrid, R. Bruce Ashman May 1955

A Cytological Study Of The Induced Octoploid Of An Agropyron-Hordeum Hybrid, R. Bruce Ashman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The occurrence of hybrids, both interspecific and intergeneric, is frequent in the Gramineae generally (Stebbins, 1949), and is especially common in the tribe Hordeae of which both A. trachycaulum and H. jubatum are members. Intergeneric hybrids in this tribe have been studied by Stebbins et al. (1946a, and 1946b), Stebbins and Walters (1949), and Stebbins and Singh (1950) in an effort to determine true phylogenetic relationships on which to base a taxonomic classification, and results of these studies have indicated that the current taxonomic treatment of this tribe is highly artificial. Attempts to produce a perennial wheat and improve …


Notes On Some Leeches (Hirudinea) From The Yukon Territory, Canada, And Alaska, M. M. Keith Apr 1955

Notes On Some Leeches (Hirudinea) From The Yukon Territory, Canada, And Alaska, M. M. Keith

Journal of the Minnesota Academy of Science

No abstract provided.


A Limnological Study Of A Farm Pond In Piedmont Virginia, Herbert Hindle Goodman Jan 1955

A Limnological Study Of A Farm Pond In Piedmont Virginia, Herbert Hindle Goodman

Theses & Honors Papers

No abstract provided.


Albino Mutants In The Golden Hamster, Robert J. Kinney Jan 1955

Albino Mutants In The Golden Hamster, Robert J. Kinney

Bachelors’ Theses

Coat color variations or other inherent changes in the golden hamster, Mesocricetus auratus Waterhouse, have been uncommon. With a few exceptions, these animals have been remarkably uniform since 1930, when they were reared in captivity for one first time.


Succession In A Dune Community At Mentor Headlands, Ohio, Harold G. Marshall Jan 1955

Succession In A Dune Community At Mentor Headlands, Ohio, Harold G. Marshall

Biological Sciences Faculty Publications

Continual sand deposition on the Lake Erie shore, adjacent to the mouth of the Grand River, has led to the formation of a developing sand dune community and through the years a successional pattern of plant growth. An analysis was made of the general plant composition of the area by means of four transects directed from the bare beach inland. Definite zonation of specific plant species was present throughout the community in parallel formation. Named for the dominant plant types they contained, the major stages were: dune grass, poplar, aspen, and oak.


Measurement Of Residual Lung Capacities And Ventilatory Efficiency By The Nitrogen Clearance Method, Elizabeth Roorbach Jun 1954

Measurement Of Residual Lung Capacities And Ventilatory Efficiency By The Nitrogen Clearance Method, Elizabeth Roorbach

Biology ETDs

Essential to an understanding of the behavior of the lung is a knowledge of its total gas capacity and those fractions of it which are utilized in the process of normal breathing. Only when these volumes are known, it is possible to make an appraisal of the efficiency of the pulmonary ventilation in maintaining physiologically adequate levels of oxygen and carbon dioxide in the alveolar spaces with a minimum of ventilatory effort.


A Study Of An Unusually Heat Resistant Variant Of Bacilius Circulans, Roberta D. Demaret Jun 1954

A Study Of An Unusually Heat Resistant Variant Of Bacilius Circulans, Roberta D. Demaret

Biology ETDs

The problem herein described was initiated while following the growth rate of a culture over a ten-hour period. A flask of polypeptone agar had been held in a 47-degree Celsius water bath to maintain it melted so that the plates could be poured periodically. The plates poured during the last two or three hours were found to be heavily contaminated with a Gram-positive, aerobic, sporeforming bacillus. Aseptic technique had been used in pouring the plates; however, external contamination was possible over the long pouring interval, so the test was repeated incubating a flask of the sterilized medium in the water …


The Nutritional Requirements Of A Strain Of Shigella Dysenteriae 1, Carl G. Mays May 1954

The Nutritional Requirements Of A Strain Of Shigella Dysenteriae 1, Carl G. Mays

Biology ETDs

It was the purpose of this investigation to develop [a synthetic] medium for the growth of Shigella dysenteriae 1, strain 14-1, originally obtained from the collection at the Army Medical Service Graduate School. Not only was it desirable to grow the cells, but also to grow them in large quantities in the least possible time. Although considerable work has been done in determining the various growth essentials for many of the Shigella group, particularly the Flexner strains of Shigella paradysenteriae, comparatively little has be ascertained regarding those strains included in Shigella dysenteriae.


Protein Metabolism In Rats With Tumors Of The Liver, Chester R. Richmond May 1954

Protein Metabolism In Rats With Tumors Of The Liver, Chester R. Richmond

Biology ETDs

The purpose of our study was to determine possible alteration in water, fat, and protein content of the livers from rats fed DAB for long periods. Aliquots were used for the protein determinations.


Microscopic Alterations In Endocrine Glands And Other Organs Of Rats Fed The Hepatic Carcinogen P-Dimethylaminoazobenzene, Fenton C. Kelley May 1954

Microscopic Alterations In Endocrine Glands And Other Organs Of Rats Fed The Hepatic Carcinogen P-Dimethylaminoazobenzene, Fenton C. Kelley

Biology ETDs

It was the purpose of this investigation to determine whether the feeding of DAB, in addition to inducing liver tumors, alters the microscopic structure of the endocrine system. In addition, a study was made of certain adrenal cortical hormones as possible modifiers of the carcinogenic effects of DAB.


Records And New Species Of Heterosphyronid Pseudoscorpions, Don L. Torgerson May 1954

Records And New Species Of Heterosphyronid Pseudoscorpions, Don L. Torgerson

Biology ETDs

Since the description of the family Chthoniidae by Hansen in 1894, the group has been revamped considerably. Most notable of these revisions are the works of Chamberlin (1931) and Beier (1932). At the present time the family contains twenty genera and several subgenera (unpublished data, C.C. Hoff). The distribution of the family Chthoniidae is cosmopolitan.


A Preliminary Study Of The Algae Of Northwestern Minnesota, Francis Drouet May 1954

A Preliminary Study Of The Algae Of Northwestern Minnesota, Francis Drouet

Journal of the Minnesota Academy of Science

No abstract provided.


The Distribution And Ecology Of The Terrestrial Shell-Bearing Mollusca Of Hanover, Henrico, And Chesterfield Counties, Virginia, John Bayard Burch Apr 1954

The Distribution And Ecology Of The Terrestrial Shell-Bearing Mollusca Of Hanover, Henrico, And Chesterfield Counties, Virginia, John Bayard Burch

Master's Theses

Very little has been published concerning the molluscan fauna of Virginia, this being also true for the area under consideration. A preliminary list of the Mollusca of Hanover County was published by J.B.Burch (1952) in which twenty-five species and subspecies of land snails were reported. Several of the land Mollusca of Henrico and Chesterfield Counties were listed by P.R. Burch (1950). These included the snails Discus patulus Deshayes, Haplotrema concavum (Say), Mesodon thyroidus (Say), Stenotrema hirsutum (Say), Triodopsis Fallax (Say), and Ventridens = (zonitoides) arboreus (Say). Two additional species, Helicodiscus parallelus (Say) and Retinella indentata (Say), were reported by personal …


A Cytotaxonomic Study Of New Mexico Thelesperma, Andrew Marion Torres Jun 1953

A Cytotaxonomic Study Of New Mexico Thelesperma, Andrew Marion Torres

Biology ETDs

This study has been an attempt to collect, to identify, and to classify the four New Mexico species of Thelesperma on the basis of morphology and chromosome number. In addition, an attempt has been made to analyze the morphology of the chromosomes with respect to their evolution.


Some Chernetid Pesudoscorpions From Mexico, Harold T. Neuberger May 1953

Some Chernetid Pesudoscorpions From Mexico, Harold T. Neuberger

Biology ETDs

Included in the collection of chernetid pseudoscorpions from the American Museum of Natural History were found several individuals representing the species and records described herein as new. Much of the present material was taken from collections made by Clarence and Marie Goodnight in the central Mexico. After publication of data in the thesis, the specimens will be returned to the permanent collections of the American Museum of Natural History.


The Interrelation Of The Adrenal And Posterior Pituitary Glands In Water And Electrolyte Metabolism, Frederic A. Giere May 1953

The Interrelation Of The Adrenal And Posterior Pituitary Glands In Water And Electrolyte Metabolism, Frederic A. Giere

Biology ETDs

The secretions of the adrenal medulla account for many of the instantaneous responses of the animal body to various stimuli, but it has not been established that such secretions play any significant role in the endocrine regulation of salt and water metabolism. On the other hand, it has been established that the adrenal cortex and the antidiuretic hormone of the posterior pituitary are intimately involved in such processes. Certain compounds of the amine type, among which are the adrenal medullary hormone, do have a dramatic action on water diuresis; but it is questioned whether these substances are involved in the …


Radiosensitivity Of Mice In Relation To Heightened Metabolic Activity During And Immediately Prior To Exposure To 220 Kv X-Rays, M. Rosalie Henneke May 1953

Radiosensitivity Of Mice In Relation To Heightened Metabolic Activity During And Immediately Prior To Exposure To 220 Kv X-Rays, M. Rosalie Henneke

Bachelors’ Theses

The manner in which certain factors influence the susceptibility of protoplasmic systems to ionizing radiations is not as yet well understood. Of prime importance among these factors is metabolic rate; it has been demonstrated that there exists a definite re­lationship between metabolic level and the lethal effects of such radiations. At the outset it must be pointed out that there are two principal problems in this connection; that is to say, radiosensitivity can be studied in relation to metabolic rate prevailing during or subsequent to exposure. One of the most frequently used criterion of radiosusceptability is mortality rate.


Isotomine Collembola From The Sandia Mountains Of New Mexico, Harold Scott May 1953

Isotomine Collembola From The Sandia Mountains Of New Mexico, Harold Scott

Biology ETDs

This paper records the first study of Collembola ever made in the Sandia Mountains and one of the first ever made in New Mexico even though the state presents excellent opportunities for study of this order. The Sandia Mountains are an ecologist’s paradise and it is probable that two hundred or more species of Collembola occur in this region alone. The entire state of New Mexico, possessing the extremes of elevation and the large geographical extent necessary to produce a great diversity of habitat types, probably contains nearly twice this number.


The Biological Sciences In The General Education Program, La Roy W. Zell May 1953

The Biological Sciences In The General Education Program, La Roy W. Zell

Journal of the Minnesota Academy of Science

No abstract provided.


Anther Development In A Male Sterile Line Of Corn, Richard J. Vogl May 1953

Anther Development In A Male Sterile Line Of Corn, Richard J. Vogl

Bachelors’ Theses

Production of viable pollen through growth and differentiation of the anther appears to depend on the interaction of the tapetum and sporogenous tissue. Very little is known about the nature of this interaction. One way to approach this problem is to study the development of the anther in cases where no viable pollen grains are produced. Highly inbred lines of male sterile corn which are completely pollen sterile have been obtained and are available for study.


An Improved Technique For The Demonstration Of Tissue Lipids, Bryan G. Hoerl Apr 1953

An Improved Technique For The Demonstration Of Tissue Lipids, Bryan G. Hoerl

Master's Theses (1922-2009) Access restricted to Marquette Campus

Progress in science frequently depends upon proper tools to demonstrate, enhance, integrate, substantiate or refute contentions. Among the means that make possible the advance of biological science is histological technique. Improved microscopic procedures result from a constant refining process and the search for new methods. To merit the adjective "improved" a new or refined technique must display a superiority to similarly employed processes. Such superiority might be shown by its speed, economy, practicality, ease or faithfulness of reproduction, or same other attribute. This paper portends to present an improved technique for the demonstration of tissue lipids .


The Respiratory Response To 6.2 Percent Carbon Dioxide And Various Concentration Of Oxygen At A Ground Level Of 5000 Ft. (Av. Bar. 630 Mm Hg), Astrid Lindholm Jan 1953

The Respiratory Response To 6.2 Percent Carbon Dioxide And Various Concentration Of Oxygen At A Ground Level Of 5000 Ft. (Av. Bar. 630 Mm Hg), Astrid Lindholm

Biology ETDs

In this study the literature has been reviewed with [the aforementioned] facts in mind. It was of interest to note the lack of agreement among investigators concerning the respiratory response not only in inhaling 100 percent oxygen, but also to breathing gas mixtures containing low oxygen. Very few papers were found in which as systematic respiratory study had been made to determine the variations in ventilation produced by a given concentration of carbon dioxide at various concentrations of oxygen. On a whole, considerable individual difference in respiration was reported and it seemed worthwhile to study carefully a specific acclimatized subject …


The Bacterial Flora Of The Alimentary Canal Of Passalus Cornutus Fabricius, George Taylor Tunstall Jan 1953

The Bacterial Flora Of The Alimentary Canal Of Passalus Cornutus Fabricius, George Taylor Tunstall

Master's Theses

The author has carried out an investigation of the bacterial flora of the alimentary canal of twenty-five specimens of Passalus Cornutus Fabricius between February and August and has described the species of organisms encountered. One hundred and eighty-two organisms were identified. Five families, six genera, and sixteen species were represented. Family Enterobacteriaceae is represented by: Escherichia freundii (Braak), Escherichia intermedium (Werkman and Gillen), Erwinia nimipressularis (Carter), Erwinia passali (sp. nov.), Erwinia intests (sp. nov.), and Erwinia virginia (sp. nov.). Only Bacterium passali (sp. nov.) is found in Family Bacteriaceae. Family Achromobacteriaceae is represented by Achromobacter passali (sp. nov.). Family Bacillaceae …


Bulletin 200 - Trees And Shrubs Of The Campus And East Central Illinois, Ernest Stover Oct 1952

Bulletin 200 - Trees And Shrubs Of The Campus And East Central Illinois, Ernest Stover

Eastern Illinois University Bulletin

The keys to the trees, shrubs and vines have been revised

in an attempt to make them more usable for the beginning student.

The keys to several of the genera, pines, oaks, ashes, willows,

etc., have been rewritten and species added that were not

in the previous printings.

The key to the trees in winter has been added hoping that it

will be helpful to both teachers and students. The identification

of trees without their leaves during the winter is not only interesting

but useful.

The identification of plants is but one phase of their study.

Botany is the basic …


The Use Of X-Ray And Nitrogen Mustard To Determine The Mitotic And Intermitotic Times In Normal And Malignant Mammalian Tissues, William Richard Widner Jun 1952

The Use Of X-Ray And Nitrogen Mustard To Determine The Mitotic And Intermitotic Times In Normal And Malignant Mammalian Tissues, William Richard Widner

Biology ETDs

The relative times involved in the various phases of cell division is basic to problems of tissue growth, but the quantitative relation of mitotic and intermitotic times have received very little attention until recently. Even data on the quantitative comparison of mammalian growth rates are very limited. The rate of growth of any tissue is directly proportional to the number of new cells added to the tissue over and above the number of old cells being constantly destroyed.

The present study was undertaken: (1) to determine which of these two factors is responsible for differences in the mitotic index seen …


Respiration Of Kidney Slices From Adrenalectomized Rats Treated With Adrenal Cortical Hormones, Miriam Landew May 1952

Respiration Of Kidney Slices From Adrenalectomized Rats Treated With Adrenal Cortical Hormones, Miriam Landew

Biology ETDs

In view of the fact that there obviously are metabolic and oxidative disturbances in the kidney caused by adrenalectomy, this investigation was attempted in an effort to obtain information concerning the following:

(1) Whether the rate of oxygen consumption of rat kidney tissue slices is a function of time; to determine whether the decreased metabolic function occurred immediately upon adrenalectomy or if an initial rise and then a falling off took place, as seemed to be indicated in the work done by Butcher (1943).

(2) Whether cortisone or desoxycorticosterone had the ability to alter oxygen consumption of kidney tissue in …


The Effects Of Epinephrine And Nor-Epinephrine On The Blood Picture In The Rat, George H. Gass May 1952

The Effects Of Epinephrine And Nor-Epinephrine On The Blood Picture In The Rat, George H. Gass

Biology ETDs

It has long been known that various stresses and stimuli elicit responses in the animal body, and since the stating of Cannon's "emergency function" (1929), the adrenal medullary hormones have been credited with exciting many of the instantaneous responses to the animal body.

The experiment was designed to determine: (1) whether nor-epinephrine has effects on the blood elements different from those seen after epinephrine treatment; (2) whether the dosage of hormone employed will affect the type of response obtained; and (3) whether the demedullated rat responds to the adrenal medullary hormones in the same pattern as the intact rat.


A Botanical Study Of The Trees And Shrubs Found On The Campus Of Ursinus College, Daniel Burnside May 1952

A Botanical Study Of The Trees And Shrubs Found On The Campus Of Ursinus College, Daniel Burnside

Biology Honors Papers

This ten page thesis gives a report of progress made in taking a botanical survey of the Ursinus College campus. Samples from all trees and shrubs of different species were collected, classified, pressed, dried and mounted. Information for plaques was created as well as a map with tree locations and a painting of an aerial view of the campus with trees plotted.


Exposure To X-Radiation Of Localized Areas Of Mammalian Skin Conditioned To Different Levels Of Metabolic Activity, James A. Belli May 1952

Exposure To X-Radiation Of Localized Areas Of Mammalian Skin Conditioned To Different Levels Of Metabolic Activity, James A. Belli

Bachelors’ Theses

There appears to be an important relationship between the overall metabolic rate prevailing in a protoplasmic system at the time of exposure to ionizing radiations and the extent of the damage effected by such radiation. It is with this issue that the present investigation is concerned.

Radiation biologists and clinical radiologists are coming to realize the importance of this problem. This increasing interest has suggested several new avenues of approach to the radiobiologist toward the elucidation of the more subtle changes occurring in protoplasmic system s exposed to radi­ation. Clinical radiology has availed itself of certain evi­dence (in a yet …