Biology Commons^™

Assessment Of P38 And Extracellular Signal-Regulated Kinase (Erk) In Regulating Apoptosis During Low And High Er Stress, Zachary G. Coffman

Featured Research

The endoplasmic reticulum (ER) is an important organelle within the cell that has many functions including protein folding. When the protein folding capabilities of the ER are compromised ER stress occurs. Extracellular signal-regulated kinases (ERKs) and p38 are MAP kinases that are induced as a result of ER stress. ERK is a protein that has been associated with cell proliferation and survival while p38 is a protein that has been associated with apoptosis, which is programmed cell death. The objective of this study was to measure ERK and p38 induction over time during low and high ER stress. Another objective …

Elevation’S Effect On Malosma Laurinais Leaf Size, Callyn E. Shelley, Nathan R. Gehring

Featured Research

Our hypothesis was that the average leaf size of Malosma laurinais would be different at high and low elevations due to the variance in temperature and solar radiation. This is especially relevant considering the severe drought conditions of California. Testing the factors of growth for chaparral may help ecologists to better understand how the plants cope with abnormalities in the ecosystem. Our study examined variance in Malosma laurinais leaf length, width, area, curvature, and thickness at high elevation (610 meters to 629 meters) and low elevation (27 meters to 53 meters) located along Sycamore Canyon. Differences were only significant in …

Flow-Induced Dilation Of Skeletal Muscle Feed Arteries: Relevance To Exercise Hyperemia, Brittni M. Moore, Jeffrey L. Jasperse

Featured Research

During exercise, an increase in blood flow to working skeletal muscle is accomplished by dilation of arteries and arterioles supplying the muscle. Arterioles, located within contracting muscle, are exposed to dilatory metabolites released by the muscle; however, the mechanism by which feed arteries, located external to the muscle, dilate is still unknown.

One potential mechanism for feed artery dilation is flow-induced dilation, occurring when arteries dilate in response to increased vascular wall shear stress. Shear stress is the frictional force between blood and the arterial wall, which increases when blood flow velocity increases. Data from previous in vitro experiments (8) …

Foliar Water Uptake And Resurrection: Mechanisms Of Drought Tolerance In Eight Species Of Ferns In The Santa Monica Mountains, Victoria M. Lekson

Featured Research

In a region where drought is severe, ecological surveys provide insight into the adaptations of organisms living on the edge of survival. In this study, the mechanisms of drought tolerance for eight species of ferns in the Santa Monica Mountains were assessed with a focus on foliar water uptake and resurrection strategies. We find that species are significantly different (P < 0.001) in their ability to absorb water through leaves (assessed gravimetrically) and correlate this to minimum seasonal water potential and hydrophobicity of leaf surfaces. Secondly, we irrigated Pentagramma triangularis in the field and tracked chloroplast recovery. We found possible evidence of embolism reversal. Taken together, this study explored the methods of survival of the most ancient family of vascular plants.

Evaluation Of The Three-Dimensional Patterns And Ecological Impacts Of The Invasive Old World Climbing Fern (Lygodium Microphyllum), Alexis Maldonado

Electronic Theses and Dissertations

Invasion by non-native species has had significant ecological and economic impacts on a global scale. In the state of Florida, Old World climbing fern (Lygodium microphyllum) is an invasive plant listed by FLEPPC as a category one invader with significant ecological impacts that threaten native plant diversity. This species relies on existing vegetative structures for support to climb into the forest canopy and forms dense mats that cover tree crowns. This subsequently affects the resources available to other species present. Quantifying the structural changes due to the presence of this species has proved logistically difficult, especially on a large spatial …

Approaches To Restoration: Assessing The Roles Of Structure And Function In Saltmarsh Restoration In Light Of Climate Change, Abby O. Pearson Ms

All Student Scholarship

The aim of this thesis is to review the current goals and methods for salt marsh restoration, to question how those goals and methods may change in light of global change, and to present a case study that offers a look at the kinds of information that can be gleaned by studying both structure and functionality in restoration.

An Avian Survey Conducted At Five Water Sources Within The Northern Chihuahuan Desert On Indio Mountains Research Station, Texas, Geoffrey Hugh Wiseman

Open Access Theses & Dissertations

The objective of this study was to conduct an avian survey of five water sources (four ephemeral former cattle tanks and one perennial spring), determine how many species inhabit or use Indio Mountains Research Station, and show a hierarchal similarity between the survey sites. This survey was conducted in a Chihuahuan Desert scrub landscape on Indio Mountains Research Station (IMRS) in Hudspeth County, Texas. There have been no previous formal studies of the avifauna at IMRS. All species accounts or sightings have been from casual sightings.

Eighty-five avian species were recorded during this project bringing the total of avian species …

Effect Of Increased Temperature And Decreased Food Quality On Metabolism And Growth Of An Algivorous Cichlid, Tropheus Duboisi And Effect Of Food Habit On The Field Metabolism Of African Cichlids., Lesley Yu-Jung Kim

Browse all Theses and Dissertations

The metabolic rate of an organism is influenced by mass, temperature, and diet. Climate change is anticipated to increase ambient temperatures of aquatic systems and decrease the quality of food available to algivorous fish. We conducted a lab experiment and a field study to quantify the influence that temperature and diet have on standard and field metabolic rate of cichlids from Lake Tanganyika. The lab experiment demonstrated the effects of increased temperature and decreased food quality on the relative growth rate (RGR) and standard metabolic rate of an algivorous cichlid, Tropheus duboisi. We found that in all temperature treatments fish …

Instructional Scientific Humor In The Secondary Classroom, Francine Wizner

Legacy Theses & Dissertations (2009 - 2024)

This study is an examination of the manner in which educators employ scientific content humor and how that humor is perceived by their students. Content humor is a useful strategy in drawing the attention of students and improving their receptivity toward scientific information. It is also a useful tool in combating the growing distractions of the electronic classroom. Previous studies have found that humor has a positive effect on knowledge, memory, and understanding. However, few studies have been conducted below the undergraduate level and mainly quantitative measures of student recall have been used to measure learning. This study employed multiple …

Full Issue: Volume 8, Number 1

The Science Journal of the Lander College of Arts and Sciences

No abstract provided.

Origins Of The Classical Gene Concept, 1900–1950: Genetics, Mechanistic, Philosophy, And The Capitalization Of Agriculture, Garland E. Allen

Biology Faculty Research

In the period of “classical genetics” (roughly 1915–1950), the common view of the gene was mechanistic—that is, genes were seen as individual, atomistic units, as material components of the chromosomes. Although it was recognized early on that genes could interact and influence each other’s expression, they were still regarded as individually functioning units, much like the chemists’ atoms or molecules. Although geneticists in particular knew the story was more complex, the atomistic gene remained the central view for a variety of reasons. It fit the growing philosophy of mechanistic materialism in the life sciences, as biologists tried to make their …

Retrospective Examination Of Habitat Use By Blueback Herring (Alosa Aestivalis) Using Otolith Microchemical Methods, Molly Payne Wynne Ms

All Student Scholarship

Life histories of anadromous fish are difficult to examine due to constraints on direct observation. However, an understanding of patterns of habitat use is critical to management efforts since recruitment to spawning age is vital to population sustainability. Blueback herring (Alosa aestivalis) are anadromous fish that utilize a variety of freshwater, estuary and nearshore marine habitats. Rapid declines in their abundance and a subsequent petition for listing under the US Endangered Species Act in 2012 have ushered in an immediate need for life history information. This study focused on five river systems and seven spawning runs along the coast of …

Co-Evolution Of Mitochondrial And Nuclear Genomes In Caenorhabditis , Emily Elaine Hill

Browse all Theses and Dissertations

Nuclear and mitochondrial genomes have co-adapted through evolution. Interactions between these genomes are required for mitochondrial functions. My goal was to determine how divergence of these interactions affected mitochondrial function and organismal fitness. The impact of divergence between Caenorhabditis briggsae populations and between C. briggsae and its sister species, C. nigoni was assessed. To accomplish this, four sets of hybrid lines were constructed. Each hybrid line possessed the nuclear genome of one parental strain and mitochondria from another parental strain. Two sets of hybrid lines were constructed from strains derived from different C. briggsae populations. The other two were constructed …

Effects Of Rev Protein On Microtubule Arrays In Living Cells, Nayana M. Nikumbh

Browse all Theses and Dissertations

The HIV protein Rev regulates the expression of essential viral proteins during the course of infection by a mechanism that is well understood. It promotes nuclear export of viral transcripts, normally retained in the nucleus owing to the presence of introns, by interacting with host cell transport factors. However, over-expression of Rev in cells leads to defects in cell cycle progression, specifically slowing growth and impairing progression through mitosis (43). While it is possible that Rev may be altering the proteins in transport pathways, cell cycle defects may be attributed to Rev's interactions with other proteins.

In vitro experiments show …

Bioc 435: Advanced Topics In Biochemistry—A Peer Review Of Teaching Project Benchmark Portfolio, Edward N. Harris

UNL Faculty Course Portfolios

BIOC 435 or Advanced Topics in Biochemistry is an ACE 10 (Achievement centered education)course for students in their senior year. This is a capstone course for Biochemistry majors and is the last of several biochemistry courses that they will take in their undergraduate enrollment. The course is also open to non-majors in a related science such as Biology and Biological Sciences, although these students typically do not do as well as the majors. Students who take this course should be well-prepared in the basic concepts of biochemistry with regards to nucleic acids and proteins as well as some familiarity with …

"Mining" For A Reference Condition In Southern West Virginia Streams, Matthew Rouch

Theses and Dissertations

Quarterly samples were used to estimate assemblage-level (all species combined) fish production within three minimally-impacted, southern West Virginia streams. The total annual fish production estimate was highest in Slaunch Fork (37.52 kg∙ha^-1∙y^-1), a tributary of the Tug Fork River, and lowest in Cabin Creek (10.59 kg∙ha^-1∙y^-1), a Guyandotte River tributary. Creek Chub Semotilus atromaculatus, Mottled Sculpin Cottus bairdii and Blacknose Dace Rhinicthys atratulus were the most abundant species among sites, accounting for >90% of all sampled individuals. Reference condition criteria were also selected and metrics calculated for each of the three …

A Seasonal, Density-Dependent Model For The Management Of An Invasive Weed, Esther Shyu, Eleanor A. Pardini, Tiffany M. Knight, Hal Caswell

Biology Faculty Research

The population effects of harvest depend on complex interactions between density dependence, seasonality, stage structure, and management timing. Here we present a periodic nonlinear matrix population model that incorporates seasonal density dependence with stage-selective and seasonally selective harvest. To this model, we apply newly developed perturbation analyses to determine how population densities respond to changes in harvest and demographic parameters. We use the model to examine the effects of popular control strategies and demographic perturbations on the invasive weed garlic mustard (Alliaria petiolata). We find that seasonality is a major factor in harvest outcomes, because population dynamics may …

Distribution And Abundance Of Anopheles Spp. In The Lower Rio Grande Valley, South Texas, Norma Hermelinda Martinez

Theses and Dissertations - UTB/UTPA

This study investigated the relationship between Anopheles abundance, collection sites and environmental variables in the Lower Rio Grande Valley, South Texas. In addition, species composition in the Lower Rio Grande Valley was determined in 2011. A total of 6772 female mosquitoes were identified to six genera and 27 species. The most prevalent genera collected were Culex (53.9%), Ochlerotatus (25.6%) and Aedes (13.6%). Anopheles mosquitoes were collected using resting boxes during summer 2012 at multiple locations along the Lower Rio Grande Valley. ArcGIS was used to identify land cover characteristics and nearest water sources at mosquito collection sites. Estero Llano Grande …

Mechanisms For Regulation Of Plant Kinesins, Anindya Ganguly, Ram Dixit

Biology Faculty Research

Throughout the eukaryotic world, kinesins serve as molecular motors for the directional transport of cellular cargo along microtubule tracks. Plants contain a large number of kinesins that have conserved as well as specialized functions. These functions depend on mechanisms that regulate when, where and what kinesins transport. In this review, we highlight recent studies that have revealed conserved modes of regulation between plant kinesins and their non-photosynthetic counterparts. These findings lay the groundwork for understanding how plant kinesins are differentially engaged in various cellular processes that underlie plant growth and development.

Conservation In The Context Of Climate Change: Practical Guidelines For Land Protection At Local Scales, Kevin Ruddock, Peter V. August, Christopher Damon, Charles Labash, Pamela Rubinoff, Donald Robadue Jr.

Natural Resources Science Faculty Publications

Climate change will affect the composition of plant and animal communities in many habitats and geographic settings. This presents a dilemma for conservation programs – will the portfolio of protected lands we now have achieve a goal of conserving biodiversity in the future when the ecological communities occurring within them change? Climate change will significantly alter many plant communities, but the geophysical underpinnings of these landscapes, such as landform, elevation, soil, and geological properties, will largely remain the same. Studies show that extant landscapes with a diversity of geophysical characteristics support diverse plant and animal communities. Therefore, geophysically diverse landscapes …

Lifelines Fall 2013, Southern Adventist University

Lifelines - Biology Department Newsletter

The Fall 2013 issue of Lifelines features articles on toxins found in nature, student missions in Tanzania, an alumni spotlight, undergraduate research, and updates on department happenings.

Acquisition Of An Electrochemical System Instrument For The Development Of Sensors, Elmer-Rico E. Mojico

Cornerstone 1 Reports : Expansion and Enhancements of the Thinkfinity Platform

No abstract provided.

"Are We Not Men?" The Effect Of Cloning On Traditional Theories Of Humanity And Personhood, Michelle Kennedy

Journal of Franco-Irish Studies

No abstract provided.

Mscs-Like Mechanosensitive Channels In Plants And Microbes, Margaret E. Wilson, Grigory Maksaev, Elizabeth S. Haswell

Biology Faculty Research

The challenge of osmotic stress is something all living organisms must face as a result of environmental dynamics. Over the past three decades, innovative research and cooperation across disciplines have irrefutably established that cells utilize mechanically gated ion channels to release osmolytes and prevent cell lysis during hypoosmotic stress. Early electrophysiological analysis of the inner membrane of Escherichia coli identified the presence of three distinct mechanosensitive activities. The subsequent discoveries of the genes responsible for two of these activities, the mechanosensitive channels of large (MscL) and small (MscS) conductance, led to the identification of two diverse families of mechanosensitive channels. …

A Force Of Nature: Molecular Mechanisms Of Mechanoperception In Plants, Gabriele B. Monshausen, Elizabeth S. Haswell

Biology Faculty Research

The ability to sense and respond to a wide variety of mechanical stimuli-gravity, touch, osmotic pressure, or the resistance of the cell wall-is a critical feature of every plant cell, whether or not it is specialized for mechanotransduction. Mechanoperceptive events are an essential part of plant life, required for normal growth and development at the cell, tissue, and whole-plant level and for the proper response to an array of biotic and abiotic stresses. One current challenge for plant mechanobiologists is to link these physiological responses to specific mechanoreceptors and signal transduction pathways. Here, we describe recent progress in the identification …

The Rate And Effects Of Spontaneous Mutation On Fitness Traits In The Social Amoeba, Dictyostelium Discoideum, David W. Hall, Sara Fox, Jennie J. Kuzdzal-Fick, Joan E. Strassmann, David C. Queller

Biology Faculty Research

We performed a mutation accumulation (MA) experiment in the social amoeba Dictyostelium discoideum to estimate the rate and distribution of effects of spontaneous mutations affecting eight putative fitness traits. We found that the per-generation mutation rate for most fitness components is 0.0019 mutations per haploid genome per generation or larger. This rate is an order of magnitude higher than estimates for fitness components in the unicellular eukaryote Saccharomyces cerevisiae, even though the base-pair substitution rate is two orders of magnitude lower. The high rate of fitness-altering mutations observed in this species may be partially explained by a large mutational target …

Evaluating Itpr-Dependence Of Apoptotic Signaling From The Endoplasmic Reticulum, Agustin Vargas, Jay L. Brewster

Featured Research

Stress within the endoplasmic reticulum (ER) can be induced by misfolded proteins accumulating in the lumen of this organelle. Signaling of ER stress to other parts of the cell results in altered gene expression, physiological adaptation, and with sustained stress, apoptosis (cell suicide). ER stress is often studied with highly toxic compounds that create severe ER stress rapidly, and a condition that is likely not physiologically relevant within an organism. In this study, we examine the apoptotic signaling induced by moderate ER stress, and in particular the inositol 1,4,5-trisphosphate receptor (ITPR). The ITPR regulates Ca2+ release from the ER lumen, …

Lysophosphatidic Acid Stimulates Lymphangiogenesis In Human Lymphatic Endothelial Cells, John Macbeth, Donna Nofziger-Plank

Featured Research

Lymphangiogenesis is the process by which new lymphatic vessels sprout and grow from existing vessels whether under developmental, immunological, or cancerous conditions. Proper lymphatic vessel formation is important in working alongside normal angiogenesis in order to help regulate the body’s tissue fluid as well as aid in immunosurveillance. Various factors regulate lymphangiogenesis such as members of the vascular endothelial growth factor family (VEGF). Another factor that has recently been identified to play a role in lymphangiogenesis is the bio-active phospholipid lysophosphatidic acid (LPA) however the molecular mechanism by which LPA regulates lymphangiogenesis has not been well characterized. In this study, …

An Ethnobotanical Approach To Finding Antimicrobial Compounds In Wooly Blue Curls (Trichostema Lanatum) Using A Kirby-Bauer Disc Diffusion Assay, Matthew C. Fleming, P. Matthew Joyner

Featured Research

Plants can be an important source of creativity and production of new drugs. In this study, extracts of wooly blue curls (Trichostema lanatum) were made using DMSO and tested for antimicrobial activity on a panel of bacteria commonly found in separate ecological niches. Wooly blue curls (WBC) was chosen due to its being recorded as a strong disinfectant by the Chumash people. It was found that WBC does exhibit antimicrobial activity against gram positive bacteria and not against gram negative bacteria. However, gram negative bacteria with reduced drug efflux function became susceptible to the WBC extract.

Carbon Black And Titanium Dioxide Nanoparticles Differentially Activate Oxidative Stress And Apoptosis In A549 Human Alveolar Epithelial Cells, Sarah Alvarado, Brianna Manes, Jay L. Brewster

Featured Research

Recent studies have demonstrated that variation between particulate matter compositions have universally adverse effects on cells and living tissues. Carbon black and titanium dioxide are two such particulates that we are continuously exposed to, yet there is limited research to examine the potential deleterious effects on living tissue. The objective of this study is to characterize the effect of carbon black (CB) and titanium dioxide (TiO2) particulates on A549 human alveolar epithelial lung cells. CB and TiO2 powders were dispersed throughout a solution of water and bovine serum albumin by high-powered sonication. The effects of these particulates on A549 cells …