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Full-Text Articles in Life Sciences
An Inducible Predator Defense In The Marine Microalga Emiliania Huxleyi (Prymnesiophyceae) Is Linked To Its Heteromorphic Haploid-Diploid Life Cycle, Amelia Kolb
WWU Graduate School Collection
Marine phytoplankton are important players in the global ecosystem, contributing up to 50% of global primary productivity. Predation by microzooplankton is one of the most important sources of mortality for phytoplankton. However, phytoplankton defenses against predators are not well understood despite their expected importance. I tested for inducible defenses in the coccolithophore Emiliania huxleyi, an abundant and ecologically important bloom-forming species with a heteromorphic haploid-diploid life cycle, against the common ciliate predator, Strombidinopsis acuminatum. The calcifying diploid and non-calcifying, flagellated haploid phases of E. huxleyi likely occupy different ecological niches, potentially explaining the maintenance of haploid-diploidy in this species. The …
Land Use, Riparian Buffers, And Biological Stream Conditions In The Puget Lowlands Of Washington, Colin Wahl
Land Use, Riparian Buffers, And Biological Stream Conditions In The Puget Lowlands Of Washington, Colin Wahl
WWU Graduate School Collection
Stream conservation and restoration strategies often focus on preserving extant riparian forest and restoring riparian habitat. In the Pacific Northwest, these efforts are often directed toward restoring and maintaining habitat that supports salmon populations. Riparian restoration, though beneficial to stream habitat, may not be sufficient to restore functioning stream ecosystems in watersheds heavily altered by intensive land use. To evaluate this hypothesis, I measured the biological condition of streams affected by human activity, and compared reaches with and without limited riparian corridors. I assessed 12 streams in watersheds dominated by different land use (cultivated, developed, forested, grassland) and sampled from …
Potential Effects Of Short-Term Climate Variation On Shrubs, Grasshoppers And Lizards In The Northern Great Basin Desert Scrub, Philip J. Dugger
Potential Effects Of Short-Term Climate Variation On Shrubs, Grasshoppers And Lizards In The Northern Great Basin Desert Scrub, Philip J. Dugger
WWU Graduate School Collection
Analyzing trophic interactions among organisms may refine our ability to predict the impacts of climate change on organismal communities in an ecosystem or biome. The Great Basin desert scrub biome comprises relatively simple biotic communities in which bottom-up trophic processes should be comparatively easy to document, analyze and understand. Observing 1) the direct effects of abiotic factors (precipitation and temperature) on desert primary producers, primary consumers, and secondary consumers and 2) the indirect effects of abiotic factors on desert community members--as mediated by biotic effects--should enhance our understanding of community trophic dynamics and may improve the accuracy of biotic predictions …
The Effects Of Elevated Pco2 On The Physiology Of Emiliania Huxleyi, Tristen Wuori
The Effects Of Elevated Pco2 On The Physiology Of Emiliania Huxleyi, Tristen Wuori
WWU Graduate School Collection
This study examined the effects of elevated CO2 on the microalga Emiliania huxleyi. Two strains were compared, a calcifying (CCMP 2668) and a non-calcifying (CCMP 374) strain. The CO2 levels used were 390 ppm, 760 ppm, and 1000 ppm. The effects of CO2 on growth rate, cell size, calcification, particulate dimethylsulfoniopropionate (DMSPp), and chlorophyll were examined. Under elevated CO2, cell size in both strains and DMSPp in the calcifying strain increased. Calcification decreased under elevated CO2. DMSPp in the non-calcifying strain and chlorophyll content in the calcifying strain had non-linear responses when exposed to elevated CO2. Growth rate in both …
Exercise Adherence In Sedentary University Employees After An 8-Week Web-Based Intervention, Summer Huntington
Exercise Adherence In Sedentary University Employees After An 8-Week Web-Based Intervention, Summer Huntington
WWU Graduate School Collection
Worksite health promotion has received attention from many researchers in an effort to find cost effective ways to improve employee health. If a simple web-based intervention is found to increase exercise adherence among sedentary adults, it may be a useful tool in improving the health of the workforce. PURPOSE: The purpose of the study was to investigate the effect of a web-based intervention on biometric measures related to exercise adherence, as well as the Stage of Change in sedentary university employees over an eight week period. METHODS: Thirty three sedentary adults were recruited from WWU university staff and faculty to …
Tts Protein Orthologs As Interspecific Reproductive Barriers In The Solanaceae, Tara D. Callaway
Tts Protein Orthologs As Interspecific Reproductive Barriers In The Solanaceae, Tara D. Callaway
WWU Graduate School Collection
TTS (transmitting tissue-specific) proteins are abundant in the extracellular matrix (ECM) of the transmitting tissue, which forms the pollen tube pathway in Nicotiana pistils. These arabinogalactan proteins stimulate pollen tube growth and are vital for optimal seed set. I have cloned and sequenced two putative orthologs, PiPRP1 and PaPRP1, which are expressed in the pistils of Petunia integrifolia and Petunia axillaris, respectively. Comparison of the domain architecture and cross-reactivity with anti-TTS protein antibodies confirm that the proteins encoded by these Petunia cDNA clones are orthologs of TTS proteins (TTSPs) from Nicotiana species. Using immunological detection methods, I have shown that …
Rnai Suppressor Screen To Identify Novel Genetic Interactors With The Sydn-1/Pfs-2 Neurodevelopmental Pathway Of Caenorhabditis Elegans And Construction Of Plasmid Vectors For Yeast-Two-Hybrid And In Vivo Analyses, Mitchell Lee
WWU Graduate School Collection
Proper development of neuronal circuits are crucial for nervous system functioning. A novel pathway regulating axon and synapse development in Caenorhabditis elegans through nuclear 3'-end polyadenylation of nascent mRNA has recently been uncovered (Van Epps et al., 2010). In this pathway, the protein product of the gene synaptic defective enhancer (sydn-1) negatively regulates polyadenylation factor subunit homolog (PFS-2), an evolutionarily conserved scaffolding protein in a multi-protein complex involved in mRNA 3' -end processing. Although 3'-end processing of mRNA has a regulatory role in many cellular processes, regulation of synapse and axon development via this cellular mechanism has not been characterized. …
Characterization Of Phprp1, An Extracellular Arabinogalactan Protein From Petunia Hybrida Pistils, Megan Twomey
Characterization Of Phprp1, An Extracellular Arabinogalactan Protein From Petunia Hybrida Pistils, Megan Twomey
WWU Graduate School Collection
An extracellular arabinogalactan protein, PhPRP1, was identified from Petunia hybrida pistils on the basis of nucleotide sequence similarity with NaTTS from Nicotiana alata and TTS-1 from Nicotiana tabacum. PhPRP1 exhibits 83% and 81% nucleotide identity with NaTTS and TTS-1 cDNAs, respectively. The amino acid sequence deduced from the cDNA predicts a 27.4 kDa polypeptide backbone with a 25 amino acid signal sequence. Sequence alignments of PhPRP1 and the TTS proteins reveals two hypervariable regions, including a proline-rich domain with noncontiguous KPP repeats. A short, highly-conserved histidinerich domain separates the two hypervariable regions. The C-terminal segment of the protein shows significant …
A Biomechanical Comparison Between A Baseball Pitch And A First Serve In Tennis, Marc A. Keller
A Biomechanical Comparison Between A Baseball Pitch And A First Serve In Tennis, Marc A. Keller
WWU Graduate School Collection
Tennis and baseball are popular sports that have similar overhand motions, but result in two different final velocities. The two sports also have different risk of injuries. The study was conducted to compare the angular kinematics of both motions. One volunteer participated in the study. Subject's shoulder and elbow angular position and velocities throghout a first serve in tennis and a fastball pitch in baseball were recorded with the use of a camera-based motion analysis system. Both the Cardan sequence (XYZ) and Euler sequence (ZYZ) were used to analyze the motions within Visual 3D. A descriptive analysis was used to …
Tidal Height And Immersion Time Impact Predator-Induced Morphological Shell Plasticity In Three Members Of The Genus Nucella, Caitlin E. O'Brien
Tidal Height And Immersion Time Impact Predator-Induced Morphological Shell Plasticity In Three Members Of The Genus Nucella, Caitlin E. O'Brien
WWU Graduate School Collection
The genus Nucella has long been used as a model to study phenotypic plasticity. Nucella lamellosa, N. canaliculata, and N. ostrina respond to waterborne cues from the predatory crab Cancer productus by thickening their shells at the apertural lip. This type of phenotypic plasticity is referred to as predator-induced morphological defense. The degree of constitutive and plastic lip thickening differs according to each species' native height in the intertidal: Nucella lamellosa lives lowest in the intertidal, typically produces the thickest shells and has the strongest response to crabs, while N. ostrina lives highest in the intertidal, has the thinnest shells, …
Promoter Deletion Analysis And Identification Of Putative Cis-Elements Of Mute In Arabidopsis, Aaron Mahoney
Promoter Deletion Analysis And Identification Of Putative Cis-Elements Of Mute In Arabidopsis, Aaron Mahoney
WWU Graduate School Collection
Stomata are found on the surfaces of land plants and are crucial for regulating gas exchange between plants and the atmosphere. These structures are composed of a pore that is surrounded by two specialized guard cells. The critical importance of stomata in providing CO2 uptake while controlling the release of water has made them a prime target for improvement of plant productivity and water use efficiency. In Arabidopsis, the production of a mature stomata requires the expression of the basic helix-loop-helix (bHLH) master regulatory gene, MUTE. The function of MUTE and its expression pattern have been characterized. In this study, …
Non-Lethal Determination Of Heavy Metals In Spiny Dogfish (Squalus Suckleyi) Spines Using La-Icp-Ms, Clayton L. (Clayton Louis) Bailes
Non-Lethal Determination Of Heavy Metals In Spiny Dogfish (Squalus Suckleyi) Spines Using La-Icp-Ms, Clayton L. (Clayton Louis) Bailes
WWU Graduate School Collection
Biological structures that develop incremental growth patterns over time present a unique opportunity to study chronological aspects of the organism's chemical environment. Spiny Dogfish (Squalus suckleyi), an abundant shark species, develop two dorsal spines that exhibit this type of growth pattern. The growth patterns on these spines have been used extensively as indicators of age. However, the chronological patterns of trace metal deposits in these spines have yet to be assessed. The main goals of this study were to develop the methods for analyzing this chronology and to explore techniques to analyze these data. Laser ablation inductively coupled plasma mass …
Lipids Of The Sea Anemone Anthopleura Elegantissima: Season And Symbiont Affect Content And Fractionation, Monica R. Ponce-Mcdermott
Lipids Of The Sea Anemone Anthopleura Elegantissima: Season And Symbiont Affect Content And Fractionation, Monica R. Ponce-Mcdermott
WWU Graduate School Collection
Anthopleura elegantissima, the common Pacific sea anemone, can host two very different algal endosymbionts: zooxanthellae (Symbiodinium muscatinei) and zoochlorellae (Elliptochloris marina). The photosynthetic carbon provided by the symbionts supplements the host's heterotrophic feeding, with zooxanthellae potentially translocating five times more carbon to the host than do zoochlorellae. We developed a method to measure lipid levels of zooxanthellate and zoochlorellate A. elegantissima in different seasons, focusing on non-polar lipids that are important components of gonad and gametes. In July 2009 and January 2010, zooxanthellate and zoochlorellate A. elegantissima were collected from the same habitat at the same tidal height. Non-polar lipids …