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Full-Text Articles in Life Sciences

A Comparative Study Of The Head And Thoracic Osteology And Myology Of The Skinks Eumeces Gilberti Van Denburgh And Eumeces Skiltonianus (Baird And Girard), David F. Nash, Wilmer W. Tanner Dec 1970

A Comparative Study Of The Head And Thoracic Osteology And Myology Of The Skinks Eumeces Gilberti Van Denburgh And Eumeces Skiltonianus (Baird And Girard), David F. Nash, Wilmer W. Tanner

Brigham Young University Science Bulletin, Biological Series

The differences observed from the osteology and myology are few and subtle.

Neither species is consistent in having all of the anatomical characters equal. E. skiltonianus, however, is more variable than gilberti. This species: 1. exhibits a wider range of variation in the number of slips of the intermandibularis anterior; 2. has two distinct bundles of the depressor mandibularis; and 3. has variation in the anterior suture pattern of the frontal, nasal, prefrontal and maxilla elements. E. gilberti on the other hand has: 1. only one distinct bundle of the depressor mandibularis; 2. a frequent reduction of the relative size …


Flora Of The National Reactor Testing Station, N. Duane Atwood Oct 1970

Flora Of The National Reactor Testing Station, N. Duane Atwood

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


Front Matter, Vol. 11 No. 4 Oct 1970

Front Matter, Vol. 11 No. 4

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


End Matter, Vol. 12 No. 1 Oct 1970

End Matter, Vol. 12 No. 1

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


Front Matter, Vol. 12 No. 1 Oct 1970

Front Matter, Vol. 12 No. 1

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


End Matter, Vol. 11 No. 4 Oct 1970

End Matter, Vol. 11 No. 4

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


Mites And Lice Of The National Reactor Testing Station, Dorald M. Allred Oct 1970

Mites And Lice Of The National Reactor Testing Station, Dorald M. Allred

Brigham Young University Science Bulletin, Biological Series

Mites of 47 species and lice of 16 species were taken from reptiles of 3 species, birds of 23 species, and mammals of 18 species at the National Reactor Testing Station between June, 1966, and September, 1967. Mammals differed in degree of infestation relative to their geographic distribution at the station. The number of species of ectoparasites which occurred on a particular kind of host generally was in direct proportion to the number of hosts examined, but exceptions occurred in some instances. In some cases the rate of infestation differed relative to the sex of the host. The greatest numbers …


A Taxonomic Comparison To Uta Stansburiana Of The Great Basin And The Upper Colorado River Basin In Utah, Lloyd C. Pack Sep 1970

A Taxonomic Comparison To Uta Stansburiana Of The Great Basin And The Upper Colorado River Basin In Utah, Lloyd C. Pack

Theses and Dissertations

The lack of a comparative study between the Uta stansburiana of the Great Basin and Upper Colorado River Basin, and the fact that several reptile species have developed distinct populations in the Upper Colorado River Basin prompted this study. Twenty-one external characteristics of these lizards were compared, including several which had not been previously used in the separation of Uta stansburiana into subspecies. All of the statistical data were obtained from preserved specimens. Twelve of the twenty-one characteristics show significant differences between the Great Basin and Upper Colorado River Basin populations. The characteristics of back pattern and throat color show …


End Matter, Vol. 11 No. 3 Sep 1970

End Matter, Vol. 11 No. 3

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


Distribution Of The Native Trees Of Utah, Kimball S. Erdman Sep 1970

Distribution Of The Native Trees Of Utah, Kimball S. Erdman

Brigham Young University Science Bulletin, Biological Series

Although botanists have been actively collecting in Utah for well over a century, the distribution of many plants are as yet imperfectly known. This is, in part, due to the scattered nature of Utah herbarium material. Also the terrain of the state has impeded collection in more rugged and remote areas. The present study gathers together the data from the major collections of native Utah trees and clarifies our present understanding of tree distributions in the state. The older collection records have been extensively supplemented by the field work of the author and other botanists.

The great diversity of environments …


Front Matter, Vol. 11 No. 3 Sep 1970

Front Matter, Vol. 11 No. 3

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


A Flora From The Dakota Sandstone Formation Near Westwater, Grand County, Utah, Samuel R. Rushforth Aug 1970

A Flora From The Dakota Sandstone Formation Near Westwater, Grand County, Utah, Samuel R. Rushforth

Theses and Dissertations

A cretaceous (Cenomanian) flora from the Dakota Sandstone Formation near Westwater, Grand County, Utah contains an admixture of ferns and angiosperms. The ferns of this flora are representative of an older Jurassic-Wealden vegetational type, whereas the angiosperms are typical of the modern vegetational type. Species of Gleichenia and Matonidium and Astralopteris coloradica represent the dominant forms in this flora. The Westwater flora contains fourteen genera including nineteen species and one variety. New species described from this flora include Asplenium dakotensis, Coniopteris westwaterensis and Ilex serrata.


The Effect Of The Parasite Hymenolepis Diminuta On Iodine Economy In The Rat, David Gourdon Holmes Aug 1970

The Effect Of The Parasite Hymenolepis Diminuta On Iodine Economy In The Rat, David Gourdon Holmes

Theses and Dissertations

A balance of iodine within the rats is important for the maintenance of normal thyroid function. Because of Hymenolepis d[imi]nuta's affinity for certain nutrients, it may upset norma[l] iodine balance in the rat. To determine this, tapeworm-infected and non-infected rats were given 125Iodide orally and the percent uptake of iodide by the thyroid and the amount of radioac[tiv]ity in the tapeworms was determined. The percent distribution of the radio-iodinated compounds in the thyroid, tapeworms and feces was also determined. These procedures were repeated except 125Thyroxine was administered orally. There was a decrease in percent iod[id]e uptake by thyroids of tapeworm-infected …


Asexual Reproduction In Planaria Characteristics Of The Inhibitor(S), Linda Gail Sheffield Aug 1970

Asexual Reproduction In Planaria Characteristics Of The Inhibitor(S), Linda Gail Sheffield

Theses and Dissertations

A study was made of the postulated fission-inhibiting substance located in the cephalic region of Dugesia dorotocephala. Rearing decapitated planaria in four different concentrations (25, 50, 75 or 100 ug/ml) of head or whole body extract resulted in a positive correlation between the inhibition of fission rate and the concentration of extract. The difference in inhibitory activity between the two types of extracts was three percent at maximum. The inhibitory substance was partially inactivated at 60° C. There was a direct correlation between the length of time that the extract was heated and the inactivation of inhibitor. The active substance …


A Study Of The Electrophoretic Patterns Of Blood Serum Proteins From Two Populations Of Mountain Whitefish (Prosopium Williamsoni), Fred Richard Hansen Aug 1970

A Study Of The Electrophoretic Patterns Of Blood Serum Proteins From Two Populations Of Mountain Whitefish (Prosopium Williamsoni), Fred Richard Hansen

Theses and Dissertations

Electrophoretic patterns on polyacrylamide gels of blood serum proteins from 74 mountain whitefish (Prosopium williamsoni Girard) were examined for differences as they pertained to two geographically isolated populations, age, and sex. Serum samples were acquired from two supposedly isolated populations, the lower Provo River and the lower Weber River. Comparisons among gels were made on the basis of protein distribution as indicated by number of fractions and their density. Serum proteins showed marked intraspecific differences between the males as well as the females of each population. No variations were found which could be attributed to degree of maturity. Definite pattern …


Evolution Of The Iguanine Lizards (Sauria, Iguanidae) As Determined By Osteological And Myological Characters, David F. Avery Aug 1970

Evolution Of The Iguanine Lizards (Sauria, Iguanidae) As Determined By Osteological And Myological Characters, David F. Avery

Theses and Dissertations

The family Iguanidae is almost completely restricted to the Western Hemisphere with its main radiations occurring in North and South America. There are also representatives on Fiji, Tonga and the Galapagos Islands, in the Pacific Ocean. Distantly related forms are also found on Madagascar off the Southeastern Coast of Africa. Although the iguanid lizards are familiar to most scientists interested in the tropics, their anatomy and evolution is poorly understood.


The Weevil Genus Tychius Germar In America North Of Mexico (Coleoptera: Curculionidae), Wayne Elden Clark Aug 1970

The Weevil Genus Tychius Germar In America North Of Mexico (Coleoptera: Curculionidae), Wayne Elden Clark

Theses and Dissertations

Weevil species assigned to the genus Tychius Germar, 1817, have been described from North and South America, Europe, Africa, Asia and Australia. The majority of approximately 266 species occur in the Mediterranean region (Klima, 1934). Fourteen native and one introduced species are known to occur in North America.


Effects Of X-Irradiation On The Brain Of White Rats, Bernell K. Dalley Aug 1970

Effects Of X-Irradiation On The Brain Of White Rats, Bernell K. Dalley

Theses and Dissertations

With the advent of the atomic age, a great deal of attention has been given to the effects of radiation of various types on the living organism. Some emphasis was placed also on the particular effects damaging radiation has on the central nervous system. Of particular importance was the dis -covery of the high resistance to irradiation exhibited by the central nervous system, and the observation of a latent period after exposure, during which the individual appears normal, followed by deterioration and death. Explan - ations of this unique reaction have caused some controversy and, currently, one of two theories …


The Effects Of Herbicide Applications On The Animal Populations Of Aspen Communities, Carl Eugene Wadsworth Aug 1970

The Effects Of Herbicide Applications On The Animal Populations Of Aspen Communities, Carl Eugene Wadsworth

Theses and Dissertations

Approximately 475 acres of aspen, oak brush, and grass-forb-shrub communities were treated with herbicides. The populations of arthropods, birds, and mammals were investigated on treated and untreated areas and the results were compared. There was no difference between soil arthropod populations on treated and untreated aspen plots but a significant increase in these populations on treated meadow plots. The foliage insect populations were significantly lower on the treated aspen plots but were significantly higher on the treated meadow plots. The aquatic invertebrates were not affected by the treatments. Bird populations ware lower in the treated area during the nesting season …


The Effects Of 2-Chloro-4-Ethylamino-6-Isopropylamino-S-Triazine (Atrazine) On The Activities Of Certain Calvin Cycle Enzymes In Barley And Corn, L. Chris Harrison Aug 1970

The Effects Of 2-Chloro-4-Ethylamino-6-Isopropylamino-S-Triazine (Atrazine) On The Activities Of Certain Calvin Cycle Enzymes In Barley And Corn, L. Chris Harrison

Theses and Dissertations

Atrazine (2-chloro-4, ethylamino-6-isopropylaminos- triazine) applied to Hordium vulgare L. variety barbless in low concentrations (0.001, 0.01, 0.1 uM) was shown to in--­ crease the activity of D-ribulose-1, 5-diphosphate carboxylase (RuDPCase) and phosphoribulokinase (PRuK) up to 23% and 30% respectively and increase the amount of chlorophyll and extractable protein up to 18% and 21% respectively over the control plants. These results indicate that sub-toxic levels of atrazine significantly stimulate plant growth. Barley plants given higher concentrations of atrazine (1.0 and 10 uM) showed up to a 78% and 42% decrease in the activity of RuDPCase and PRuK respectively as well as …


Asexual Reproduction In Planaria Studies On Inhibition, Hal R. Fitzgerald Aug 1970

Asexual Reproduction In Planaria Studies On Inhibition, Hal R. Fitzgerald

Theses and Dissertations

The invertebrates display several methods of asexual reproduction, such as fission and gemnule formation and budding (Hay, 1966). Planaria reproduce asexually only by fission.


Aquatic And Semi-Aquatic Plant Communities Of Utah Lake, Robert E. Coombs Aug 1970

Aquatic And Semi-Aquatic Plant Communities Of Utah Lake, Robert E. Coombs

Theses and Dissertations

The aquatic and semi-aquatic plant communities of Utah Lake, Utah County, Utah are discussed. This discussion includes the methods of describing and delimiting the major vascular plant communities, the descriptions of the present existent communities, and the determination of the vegetational changes, particularly since 1925. The vegetation around Utah Lake is divided into plant communities. Each community is discussed using: (a) quantitative data, (b) field observations, (c) general and specific locations of the community, and (d) interrelationships and trends of the community. Historical vegetational changes of Utah Lake plant communities are discussed. In this discussion, the plant communities described by …


A Comparative Study Of The Head And Thoracic Osteology And Myology Of The Skinks, Eumeces Gilberti Van Denburgh And Eumeces Skiltonianus (Baird And Girard), David F. Nash Jul 1970

A Comparative Study Of The Head And Thoracic Osteology And Myology Of The Skinks, Eumeces Gilberti Van Denburgh And Eumeces Skiltonianus (Baird And Girard), David F. Nash

Theses and Dissertations

Further clarification of the taxonomic and phylogenetic relationships of Eumeces gilberti and Eumeces skiltonianus is achieved by the comparisons of the skull, mandible elements, and the anterior myology of these two species. Figures are provided to compliment the descriptions. The study confirms their close relationship and few differences are observed. E. skiltonianus, however, appears to have more anatomical plasticity which suggests that E. gilberti may have arisen from the former.


Osteological And Mylogical Comparisons Of The Head And Thorax Regions Of Cnemidophorus Tigris Septentrionalis Burger And Ameiva Undulata Parva Barbour And Nobel (Family Teiidae), Don Lowell Fisher, Wilmer W. Tanner Jun 1970

Osteological And Mylogical Comparisons Of The Head And Thorax Regions Of Cnemidophorus Tigris Septentrionalis Burger And Ameiva Undulata Parva Barbour And Nobel (Family Teiidae), Don Lowell Fisher, Wilmer W. Tanner

Brigham Young University Science Bulletin, Biological Series

The anterior osteological elements of the skull, lower jaw, and wrist along with the anterior myological characters discussed and figured in this report suggest that A. u. parva and C. t. septentrionalis are members of distinct groups which can be differentiated by internal morphologic characters. Although comparisons were restricted to highly geographically separated individuals of the same family, their general body form and structure appear to be similar.

A great number of anatomical structures are shared in common, but the significant differences between them include:

1. General skull appearance. The skull of C. is generally lighter, that is the bones …


Pinyon-Juniper Succession After Natural Fires On Residual Soils Of Mesa Verde, Colorado, James A. Erdman Jun 1970

Pinyon-Juniper Succession After Natural Fires On Residual Soils Of Mesa Verde, Colorado, James A. Erdman

Brigham Young University Science Bulletin, Biological Series

A mountain brush vegetation typified by Gambel oak (Quercus gambelii) and serviceberry (Amelanchier utahensis) dominates the uplands of Mesa Verde National Park. There is evidence that this brush element is a successional stage that has been maintained by repeated natural fires in a large part of the Mesa Verde landscape. This study was conducted to determine the role of fire in the region's ecology, the nature of the climax pinyon pine (Pinus edulis) and Utah juniper (Juniperus osteosperma) vegetation, and the major successional stages that lead to the climax condition.

Three postburn …


End Matter, Vol. 11 No. 2 Jun 1970

End Matter, Vol. 11 No. 2

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


Front Matter, Vol. 11 No. 2 Jun 1970

Front Matter, Vol. 11 No. 2

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


End Matter, Vol. 11 No. 1 Jun 1970

End Matter, Vol. 11 No. 1

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


Calorigenic Effects Of Thyroxine And Triiodothyronine On Rat Diaphragm., Robert Lee Chambers Jun 1970

Calorigenic Effects Of Thyroxine And Triiodothyronine On Rat Diaphragm., Robert Lee Chambers

Theses and Dissertations

Since the isolation of triiodothyronine (T3) by Pitt-Rivers and Gross (1953) several questions as to its role as a thyroid hormone arose. Does T3 have the same or different actions than that of thyroxine (T4 )? Is T3 an emergency hormone, since its synthesis relative to T4 is greatly increased during periods of low iodine intake and its response time is I/5th that of T4 (Ackerman and Arons, 1958)? Are there any interactions modifying their respective actions?


Front Matter, Vol. 11 No. 1 Jun 1970

Front Matter, Vol. 11 No. 1

Brigham Young University Science Bulletin, Biological Series

No abstract provided.