Life Sciences Commons^™

Effects Of Participation In Inquiry Science Workshops And Follow-Up Activities On Middle School Science Teachers' Content Knowledge, Teacher-Held Misconceptions, And Classroom Practices, Linda F. Cepeda

Electronic Theses and Dissertations

An important aspect of developing science literacy for all students is developing science-literate teachers. With the implementation of the No Child Left Behind Act, many middle school teachers found themselves in a position where they were no longer qualified to teach middle school science. This study was designed to help science teachers increase their science content knowledge, identify and resolve misconceptions/errors they may have, and assist them in their teaching by providing strategies for inquiry-based teaching, science laboratory exercises, and science equipment.

Teachers enrolled in biology courses offered by the Rocky Mountain Middle School Math and Science Partnership participated in …

Factors Affecting Breeding Territory Size And Placement Of The Florida Grasshoper Sparrow (Ammodramus Savannarum Floridanus), Jill Aldredge

Electronic Theses and Dissertations

For most taxa, maximizing fitness depends on maintaining access to adequate resources. Territories provide exclusive use of resources for an individual or a family group, thus facilitating successful reproduction. The economic defensibility of a territory depends on the quality, abundance, and distribution of its resources as well as the amount of competition that an individual must endure to maintain exclusive access. The benefits of defense must outweigh the costs for territoriality to be profitable. Territory owners may benefit from territories with high quality resources, but they also may incur greater costs defending these resources from competitors. In contrast, territories with …

Factors Affecting Predation Of Marine Turtle Eggs By Raccoons And Ghost Crabs On Canaveral National Seashore, Fl, Justin Brown

Electronic Theses and Dissertations

Changes in abundance of interactive species can have cascading, community-wide effects (Soule et al. 2003). Raccoons (Procyon lotor) prey on a competitor for marine turtle eggs, the Atlantic ghost crab (Ocypode quadrata). Conservation of marine turtles often includes managing raccoons-the most obvious egg predator-which may have broader ecological effects, and unknown effects on egg predation. Neither the relationship between raccoons and ghost crab density nor the effects of ghost crab density on egg predation are well understood. I studied raccoon-ghost crab interactions and the effects of environmental variation on their activity during the 2007 marine turtle nesting season on Canaveral …

The Effects Of Urbanization On The Structure, Quality, And Diversity Of Cypress Plant Communities In Central Florida, Courtney Knickerbocker

Electronic Theses and Dissertations

The integrity of wetland ecosystems is largely determined by hydrological functionality, degree of connectivity to like ecosystems, and permeability to external influence. Land use changes in upland areas adjacent to wetland ecosystems may influence hydrology and connectivity while introducing novel biotic and abiotic materials. There is an increasing trend toward the use of remote assessment techniques to determine the degree of impact of external influences on adjacent wetlands. Remote assessment and predictive capabilities are provided by indices such as the Landscape Development Intensity Index (LDI) (Brown and Vivas 2005) which may be beneficial in determining site condition, and which have …

Habitat Use By The Southeastern Beach Mouse (Peromyscus Polionotus Niveiventris) At Cape Canaveral Air Force Station, Florida, Kathryn Simmons

Electronic Theses and Dissertations

Successful recovery of the federally threatened southeastern beach mouse (Peromyscus polionotus niveiventris) depends in part on an understanding of their habitat requirements. I studied habitat use by beach mice at Cape Canaveral Air Force Station, Florida from March 2005 until March 2006. I livetrapped six grids, three on coastal dunes and three within scrub located inland from the coast. On each grid and trap station, I quantified the extent of bare ground, woody vegetation, non-woody vegetation, height of vegetation, and percentage of coarse sand in the surface soil. I assessed trap success relative to these habitat variables using linear and …

Landcover Change And Population Dynamics Of Florida Scrub-Jays And Florida Grasshopper Sparrows, David Breininger

Electronic Theses and Dissertations

I confronted empirical habitat data (1994-2004) and population data (1988-2005) with ecological theory on habitat dynamics, recruitment, survival, and dispersal to develop predictive relationships between landcover variation and population dynamics. I focus on Florida Scrub-Jays, although one chapter presents a model for the potential influence of habitat restoration on viability of the Florida Grasshopper Sparrow. Both species are unique to Florida landscapes that are dominated by shrubs and grasses and maintained by frequent fires. Both species are declining, even in protected areas, despite their protected status. I mapped habitat for both species using grid polygon cells to quantify population potential …

Understanding Plant Community Composition In Agricultural Welands: Context Dependent Effects And Plant Interactions, Elizabeth Boughton

Electronic Theses and Dissertations

Community composition results from an integrated combination of random processes, regional habitat spatial structure, local environmental conditions, and species interactions. For example, the outcome of plant interactions can change depending on local environmental conditions such as nutrient availability, land management, or herbivory intensity. In particular, plant interactions may vary between facilitation and competition depending on ecological context, with facilitation expected to be prevalent under stressful conditions. I present the results of four studies that address different aspects of the community assemblage and dynamics emphasizing the synergistic effect of different processes. In the first, I investigated the importance of habitat isolation …

Role Of Pro-Apoptotic Bcl2-Homology-3 Domain (Bh3)-Only Proteins In The Mutant Sod1 Mouse Model Of Als, Anna George Andrianakos

Electronic Theses and Dissertations

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease involving rapid degeneration of motor neurons in the spinal cord and retraction of their axonal projections to the neuromuscular junctions. Several known mutations linked to some familial cases of ALS have been linked to mutations in Cu/Zn superoxide dismutase (SOD1), resulting in mitochondrial oxidative stress and intrinsic apoptosis. Transgenic mice expressing a G93A mutant of SOD1 provide an in vivo model to investigate motor neuron death during disease progression. The principal regulators of intrinsic apoptosis are the Bcl-2 family proteins. While some members of this family are pro-survival, the Bcl-2 homology-3 …

Assessing Crosstalk Between Calcium And Camp In Pancreatic Alpha Cells, Julianne Michelle Imseis

Electronic Theses and Dissertations

Blood glucose levels are regulated by the interactions between insulin and glucagon. Pancreatic alpha cells release glucagon in response to a drop in blood sugar. Pancreatic alpha cells appear to be regulated through multiple signaling pathways. One potential method of regulation occurs from α-MSH or epinephrine stimulated production of the intracellular messenger cyclic AMP. Exocytosis of dense core vesicles containing glucagon ultimately requires an increase in cytosolic calcium. This study focused on the link between cyclic AMP and calcium in pancreatic alpha cells which allows alpha cell regulation. Interactions between calcium and cyclic AMP in pancreatic alpha cells consists of …

Quantifying Soil And Groundwater Chemistry In Areas Invaded By Tamarix Spp. Along The Middle Rio Grande, New Mexico, Michelle Kelly Ohrtman

Electronic Theses and Dissertations

Tamarix spp. (a.k.a. saltcedar, tamarisk) invasion is considered a major ecological threat at both national and global levels, with supposed impacts on soil and water chemistry. One of the most often cited mechanisms of ecosystem change by Tamarix is through its ability to deposit salty exudates and salt-rich leaf litter. The degree to which Tamarix relates to elevated soil and groundwater salinity, however, has not been adequately quantified, especially in the context of environmental factors that may also influence salinity. If Tamarix does elevate localized salinity by means of uptake, concentration and exudation by plant tissues, then we might expect …

Amino Acid Residues Implicated In The Interaction Of Melanocortin Ligands And Their Receptors: A Study Of Mc2r Selectivity, Kristopher D. Veo

Electronic Theses and Dissertations

Melanocortin receptor ligand selectivity has been a question not easily answered. The inability to functionally express melanocortin 2 receptor (MC2R) has inhibited the study of why MC2R is only stimulated by ACTH, a melanocortin hormone. With the recent discovery of the MC2R accessory protein (MRAP), creating a heterologous system is now feasible. Using a general cell line like CHO-K1 cells, which do not express endogenous MCRs, we were able to create a heterologous expression system and test the selectivity of MC2R using analog variants of ACTH(1-24). Our results indicate an amino acid requirement in the C-terminal portion of ACTH(1-24) for …

Structure-Function Analysis Of Endoproteolytic Cleavage: Site-Directed Mutagenesis Studies Of The Α-Msh Cleavage Site In Silurana Tropicalis Pomc, Quinn Kun Chen

Electronic Theses and Dissertations

The maturation process of many prohormone molecules typically requires endoproteolytic cleavage C-terminal of dibasic residues, such as the K¹⁴¹R¹⁴²↓ site N-terminal of the α-melanocyte stimulating hormone (α-MSH) sequence in Silurana tropicalis proopiomelanocortin (POMC). In order to determine the absolute requirement of basic amino acid residues in the cleavage process, site-directed mutagenesis was employed to substitute alanine for the wild-type residues in the frog POMC open reading frame. Specifically, the following underlined residues were individually targeted for alanine substitution: R ¹³⁷ Q ¹³⁸ E ¹³⁹ N ¹⁴⁰ K ¹⁴¹ R ¹⁴²↓. The mouse pancreatic αTC1.9 cell …

Native Fire Regime As A Reference For Establishing Management Practices, Brean Duncan

Electronic Theses and Dissertations

Our understanding of natural fire regimes in human-dominated landscapes is limited. Fire regimes operating in the pyrogenic ecosystems of Florida have been altered by fire suppression and fuel fragmentation. This is especially true of North Merritt Island, Florida, where human impacts have led to an incomplete knowledge of current fire regimes. We know that growing season fires frequently occurred within general return intervals and that many native terrestrial species require fire to remain viable. A 20-year plus period of fire suppression caused structural and compositional changes to vegetation/fuels that led to catastrophic fires and the decline of native species populations …

Tissue Engineered Myelination And The Stretch Reflex Arc Sensory Circuit: Defined Medium Formulation, Interface Design And Microfabrication, John Rumsey

Electronic Theses and Dissertations

The overall focus of this research project was to develop an in vitro tissue-engineered system that accurately reproduced the physiology of the sensory elements of the stretch reflex arc as well as engineer the myelination of neurons in the systems. In order to achieve this goal we hypothesized that myelinating culture systems, intrafusal muscle fibers and the sensory circuit of the stretch reflex arc could be bioengineered using serum-free medium formulations, growth substrate interface design and microfabrication technology. The monosynaptic stretch reflex arc is formed by a direct synapse between motoneurons and sensory neurons and is one of the fundamental …

Host And Seasonal Effects On The Infection Dynamics Of Skrjabinoptera Phrynosoma (Ortlepp) Schulz, 1927, A Parasitic Nematode Of Horned Lizards, Kathryn Claire Hilsinger

Electronic Theses and Dissertations

Author's Abstract: Skrjabinoptera phrynosoma (Ortlepp) Schulz, 1927 is a common parasitic nematode of horned lizards. The life cycle of S. phrynosoma was described by Lee in 1957, but has received little attention since. The present study addressed effect of season as well as host characteristics on the infection dynamics in lizard hosts. In the Alvord Basin in southeastern Oregon, S. phrynosoma were collected from Phrynosoma platyrhinos Gerard 1852 horned lizards via stomach flushes, cloaca flushes and fecal pellet collections. Parasite load variables (number of nematodes per host, length of those nematodes, and total worm burden (ΣL)) were analyzed within three …

Tidal Influences On Bacterial And Phytoplankton Abundances And The Resulting Effects On Patterns Of Dissolved Oxygen In The Skidaway River Estuary, Casey Colleen Brazell

Electronic Theses and Dissertations

Two studies were conducted to investigate the physical and biological processes contributing to the dissolved oxygen (DO) availability in the Skidaway River Estuary (SRE), Savannah, GA during the summer of 2005. A temporal study looked at changes in DO concentrations, Chlorophyll a concentrations, bacterial abundance, water depth, and salinity, every hour, for 26 hours, over both a neap and a spring tide. A spatial study looked at changes in the above variables at 5 sites along the SRE while following the tide inland during a neap high and low tide, and a spring high and low tide. DO concentrations varied …

Effects Of Habitat Quality On Reproduction In Two Georgia Populations Of Gopherus Polyphemus, Jaqueline W. Entz

Electronic Theses and Dissertations

Author's Abstract: The purpose of this study was to examine differences in maternal investment by examining variation in the habitat structure and reproductive parameters for two populations of Gopherus polyphemus in Southeast GA. Both habitat structure and reproductive parameters for these populations are known from a previous study, thus this study expands upon the previous one and addresses four main questions. (1) Has habitat quality changed in the past ten years within and between population sites? (2) Could a change of habitat have affected female morphology or female reproductive parameters within or between populations? (3) Is female body size shaping …

Reintroduction Of Bison (Bison Bison) On Reservations In South Dakota: Four Case Studies, Trudy M. Ecoffey

Electronic Theses and Dissertations

This research explored and documented issues of sustainability associated with the reintroduction of bison in four different bison herds on Reservations in South Dakota. The four herds were managed by: a tribal family cooperative, an individual tribal member, a tribal university and a tribal fish and wildlife agency. The objectives were to identify management practices associated with the sustainability of bison introduction by American Indians; to explore the role of American Indian culture in the management of bison for sustainability; and to investigate rangeland criteria that could be used to measure sustainability of bison reintroduced by American Indians. This project …