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Factors Influencing Nest Site Selection By Wood Turtles (Glyptemys Insculpta) In An Altered Forest Landscape, Ellery Ruther

Theses & Honors Papers

There have been many studies concerning wood turtle (Glyptemys insculpta) nest site selection, including studies that evaluate nest site conditions when stream sand banks are not available. However, because of the unique landscape at our study site (high gradient, first order streams) and rapidly diminishing wood turtle populations in Virginia, I am evaluating wood turtle nest site selection. Nine physiographic and vegetative characteristics from nest, positive, negative-one and negative-two control locations were evaluated using binomial generalized linear models and then best fit models were chosen using Akaike's Information Criterion (AIC). It was found that in lieu of typical stream …

Bat Community Dynamics And Foraging Activity Patterns In Young Regenerating Southern Pine Plantations And Mixed Hardwood Forests, Kathryn Marie Womack

Theses & Honors Papers

Forests of the southeastern U.S. are changing rapidly in species composition and extent of forest cover due to increasing conversion to pine (Pinus sp.) plantations , intensifying management practices, and expanding urbanization and sprawl. Questions related to the impacts of these changes on wild life species are of great conservation interest and management relevance. Highly mobile species with large home ranges and complex habitat requirements , such as bats, may be especially vulnerable to increasing human modification of landscapes. However, the impacts of such modifications on bat species are poorly understood . I sought to evaluate bat community structure and …

Survey Of Amphibians And Reptiles In Powhatan County, Virginia With Selected Natural History Notes, Jason Daniel Gibson

Theses & Honors Papers

This thesis establishes baseline data on the herpetofauna that exist in Powhatan county. No systematic study of the amphibians and reptiles in Powhatan county has ever been conducted. The methods used in this survey include hand capture, egg mass observations, road kill collections, and frog call surveys. Documentation of each species collected included measurements, photographs, range maps, and tape recordings.

This survey produced 8 species of salamanders, 11 anurans, 6 turtles, 4 lizards, and 14 snakes. Based on records in the Atlas of Amphibians and Reptiles of Virginia (Mitchell & Reay, 1999), 11 new county records were discovered. This brings …

Biological Determinism And The Human Genome Project: Is The Past Prologue?, Alexandra Dawn Breen

Theses & Honors Papers

In 1989, The National Institutes of Health, in collaboration with the United States Department of Energy, launched a three billion dollar project that could potentially change the way we view human life. The purpose of the project is to map every gene on every chromosome of the human DNA. The Human Genome Project, as it is referred to, is scheduled for completion by the year 2005. The frank reality of the Human Genome Project is that it will indeed offer some real and measurable benefit to different types of people, including some of those inflicted with fatal diseases and disorders; …

Fractionation Of Biologically Active Nucleic Acid Extract Of Volvox Aureus, Lucy Ann Gresham

Theses & Honors Papers

The colonial flagellate Volvox has been under study recently because its pattern of differentiation is simple and because it synthesizes chemical substances that induce or influence specific stages in its development (Darden, 1970; Starr , 1970). Volvox shows cellular differentiation and division of labor but has a maximum of four cell types, making Volvox's cellular diversity among the least complex of multicellular organisms . Chemical induction systems for males, females, and parthenospores are known for several species.

Male differentiation in Volvox aureus M5 is controlled by a male inducing substance (MIS) obtained from filtrates of sexual cultures (Darden, 1966). MIS …

The Flora Of The Headwaters Of Cornelius Creek, Botetourt County, Virginia, Thelma H. Dalmas

Theses & Honors Papers

The headwaters of Cornelius Creek support a rich flora characteristic of seepage areas at high altitudes on north facing slopes f the central Blue Ridge Mountains. In the two acres studied, three ecological habitats were encountered; a dry forested tract, a wet forested tract, and an open glade. Some of the species of vascular plants which are present are representative of a more northern flora. One hundred and twenty vascular plants and twenty-five bryophytes were collected and deposited in the herbaria at the Peaks of Otter and Longwood College.

A Comparative Study Of The Effects Of Starvation On Two Mating Types Of Tetrahymena Pyriformis, Carolyn Gene Mohler

Theses & Honors Papers

The initial observable event in protozoan conjugation is the union, by pairs, of cells belonging to opposite mating types. The union does not occur immediately after mixing appropriate mating types; a starvation-initiated period (the refractory period) of approximately 4 hours is prerequisite for mating between the two mating types of variety 1, Tetrahymena pyriformis employed in this study.

The results of this study indicate that water-diffusible mating substances are produced by the mating types during the refractory period. The production of these substances is initiated by placing the cells under starvation conditions and not by contacts among cells of opposite …

A Comparative Analysis Of Amino Acids In Tetrahymena Pyriformis Under Feeding And Starvation Conditions, Jeanne Whitaker Clabough

Theses & Honors Papers

No abstract provided.

Effects Of Ultraviolet Radiation On Growth In Partially Shielded Timothy Roots, Mary Beth Picinich

Theses & Honors Papers

No abstract provided.

An Historical And Experimental Account Of Geotropism, Nancy Redd Quarles

Theses & Honors Papers

The fact that shoots grow upwards and roots grow downwards is common knowledge. These recognized tendencies are called "geotropic reactions". We apply the term, "positive geotropism" to the tendency of roots growing downwards; meaning that they respond in a positive manner to the pull of gravity. To the response of shoots we apply the term, "negative geotropism", which signifies that their growth is away from the pull of gravity.

The response of plants to external forces such as gravity has long been a subject of research. Many theories have been advanced attempting to explain the basic principles involved in the …

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

Theses & Honors Papers

No abstract provided.

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

Theses & Honors Papers

No abstract provided.