Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Biology (133)
- Ecology and Evolutionary Biology (7)
- Physical Sciences and Mathematics (3)
- Animal Sciences (2)
- Computer Sciences (2)
-
- Genetics and Genomics (2)
- Aquaculture and Fisheries (1)
- Behavior and Ethology (1)
- Biochemistry, Biophysics, and Structural Biology (1)
- Biodiversity (1)
- Bioinformatics (1)
- Biophysics (1)
- Education (1)
- Electrical and Computer Engineering (1)
- Engineering (1)
- Entomology (1)
- Environmental Sciences (1)
- Forest Sciences (1)
- Genetics (1)
- Genomics (1)
- Higher Education (1)
- Mathematics (1)
- Science and Mathematics Education (1)
- Zoology (1)
- Keyword
-
- Climate change (4)
- Eastern Coyote (3)
- Allozymes (2)
- Anthropogenic disturbance (2)
- Drosophila (2)
-
- Environmental bootstrap (2)
- Genetic diversity (2)
- Herbivory (2)
- Luteinizing hormone (2)
- Macroalgae (2)
- Management (2)
- Myrmecophyte (2)
- Open source (2)
- Proteomics (2)
- 3D printing (1)
- 43 foraging behavior (1)
- Affiliation (1)
- Agroforestry (1)
- Alien species (1)
- Allelopathy (1)
- Alpha diversity (1)
- Ant-plant interactions (1)
- Anticoagulant (1)
- Argiope trifasciata (1)
- Authentication (1)
- Automatic graph layout (1)
- Barcoding (1)
- Behavioral ecology (1)
- Behavioural study (1)
- Best practices for scientific computing (1)
Articles 121 - 136 of 136
Full-Text Articles in Life Sciences
Responses Of Cam Species To Increasing Atmospheric Co2 Concentrations, Philippa M. Drennan
Responses Of Cam Species To Increasing Atmospheric Co2 Concentrations, Philippa M. Drennan
Biology Faculty Works
Crassulacean acid metabolism (CAM) species show an average increase in biomass productivity of 35% in response to a doubled atmospheric CO2 concentration. Daily net CO2 uptake is similarly enhanced, reflecting in part an increase in chlorenchyma thickness and accompanied by an even greater increase in water-use efficiency. The responses of net CO2 uptake in CAM species to increasing atmospheric CO2 concentrations are similar to those for C3 species and much greater than those for C4 species. Increases in net daily CO2 uptake by CAM plants under elevated atmospheric CO2 concentrations reflect increases in both Rubisco-mediated daytime CO2 uptake and phosphoenolpyruvate …
Mechanisms Of Convergence And Extension By Cell Intercalation, Maxellende Ezin
Mechanisms Of Convergence And Extension By Cell Intercalation, Maxellende Ezin
Biology Faculty Works
The cells of many embryonic tissues actively narrow in one dimension (convergence) and lengthen in the perpendicular dimension (extension). Convergence and extension are ubiquitous and important tissue movements in metazoan morphogenesis. In vertebrates, the dorsal axial and paraxial mesodermal tissues, the notochordal and somitic mesoderm, converge and extend. In amphibians as well as a number of other organisms where these movements appear, they occur by mediolateral cell intercalation, the rearrangement of cells along the mediolateral axis to produce an array that is narrower in this axis and longer in the anteroposterior axis. In amphibians, mesodermal cell intercalation is driven by …
Dg93, A Nodule-Abundant Mrna Of Datisca Glomerata With Homology To A Soybean Early Nodulin Gene, Nancy Fujishige
Dg93, A Nodule-Abundant Mrna Of Datisca Glomerata With Homology To A Soybean Early Nodulin Gene, Nancy Fujishige
Biology Faculty Works
We have isolated a 590-bp full-length cDNA clone designated Dg93, an mRNA that is highly expressed in symbiotic root nodules of the actinorhizal host Datisca glomerata. Dg93 mRNA encodes a deduced polypeptide of 105 amino acids with significant identity (74%) to the soybean (Glycine max) early nodulin (ENOD) gene GmENOD93 (Kouchi and Hata, 1993). Dg93 mRNA is abundant in nodules at 4 weeks post inoculation, the earliest time assayed, and steady-state mRNA levels remain elevated 11 weeks after inoculation. Spatial patterns of Dg93 mRNA expression are complex, with transcript accumulation in the nodule lobe meristem, early infection zone, periderm, and …
Gene Flow Among Habitat Patches On A Fragmented Landscape In The Spider Argiope Trifasciata (Araneae: Araneidae), Martina G. Ramirez, Kirsten E. Haakonsen
Gene Flow Among Habitat Patches On A Fragmented Landscape In The Spider Argiope Trifasciata (Araneae: Araneidae), Martina G. Ramirez, Kirsten E. Haakonsen
Biology Faculty Works
The banded garden spider (Argiope trifasciata) is a common orb weaver of old field habitats in the United States. In this study, we determined levels of genetic variability and gene flow among seven populations in central Pennsylvania, based on variation at eight allozyme loci. Mean heterozygosity (observed) per population was 7.5% and mean polymorphism was 39.3%, consistent with levels of variability in other arthropods. Values of GST for the four polymorphic loci (mean GST=0.011) suggest that gene flow prevents the genetic differentiation of these populations. The average number of migrants per generation (Nm) among …
Root Growth Dependence On Soil Temperature For Opuntia Ficus-Indica: Influences Of Air Temperature And A Doubled Co2 Concentration, Philippa M. Drennan
Root Growth Dependence On Soil Temperature For Opuntia Ficus-Indica: Influences Of Air Temperature And A Doubled Co2 Concentration, Philippa M. Drennan
Biology Faculty Works
1. Root elongation as a function of soil temperature was determined for the CAM succulent Opuntia ficus-indica, under three different day/night air temperatures (15 °C/5 °C, 25 °C/15 °C and 35 °C/25 °C) and an ambient (360 μmol mol-1) vs a doubled CO2 concentration (720 μmol mol-1) at 25 °C/15 °C, the optimum temperature for net CO2 uptake. 2. Root elongation occurred at soil temperatures from 12 °C (at 15 °C/5 °C) to 43 °C (at 35 °C/25 °C) with optimum temperatures of 27-30 °C, similar to other CAM succulents and consistent with the distribution of this shallow-rooted species in …
Expression Of Early Nodulin Genes In Alfalfa Mycorrhizae Indicates That Signal Transduction Pathways Used In Forming Arbuscular Mycorrhizae And Rhizobium-Induced Nodules May Be Conserved, Nancy Fujishige, Michelle R. Lum
Expression Of Early Nodulin Genes In Alfalfa Mycorrhizae Indicates That Signal Transduction Pathways Used In Forming Arbuscular Mycorrhizae And Rhizobium-Induced Nodules May Be Conserved, Nancy Fujishige, Michelle R. Lum
Biology Faculty Works
Transcripts for two genes expressed early in alfalfa nodule development (MsENOD40 and MsENOD2) are found in mycorrhizal roots, but not in noncolonized roots or in roots infected with the fungal pathogen Rhizoctonia solani. These same two early nodulin genes are expressed in uninoculated roots upon application of the cytokinin 6-benzylaminopurine. Correlated with the expression of the two early nodulin genes, we found that mycorrhizal roots contain higher levels of trans-zeatin riboside than nonmycorrhizal roots. These data suggest that there may be conservation of signal transduction pathways between the two symbioses-nitrogen-fixing nodules and phosphate-acquiring mycorrhizae.
Genetic Variability And Gene Flow In Metepeira Ventura (Araneae, Araneidae), Martina G. Ramirez
Genetic Variability And Gene Flow In Metepeira Ventura (Araneae, Araneidae), Martina G. Ramirez
Biology Faculty Works
Levels of genetic variability and gene flow among three populations of Metepeira ventura o n Santa Catalina Island, California, were evaluated based on variation at 10 gene loci . Mean heterozygosity (observed) per population was 10 .4% and mean polymorphism was 36 .7%, consistent with levels of variabilit y in other arthropods. Values of FST for the five polymorphic loci (mean FST = 0 .009) suggest that gene flow prevents the genetic differentiation of these populations . The average number of migrants per generation (Nm) among these populations is estimated to be 28 .6 . The lack of inter-population genetic …
Natural History Of The Spider Genus Lutica (Araneae, Zodariidae), Martina G. Ramirez
Natural History Of The Spider Genus Lutica (Araneae, Zodariidae), Martina G. Ramirez
Biology Faculty Works
Spiders of the genus Lutica are fossorial inhabitants of coastal dunes of southern California, Baja California and the California Channel Islands. They live in silk-lined burrows concentrated beneath dune vegetation. Lutica are sit-and-wait predators that subdue insects that walk near or over burrows . They are sedentary and do not engage in aerial dispersal via ballooning . Adult males abandon their burrows during the late summer and early fall to wander in search of females . Females produce eggsacs and guard them till they die; spiderlings emerge in the spring. Dune trapdoor spiders (Aptostichus simus) prey on Lutica, …
Phylogeny And Historical Biogeography Of The Spider Genus Lutica (Araneae, Zodariidae), Martina G. Ramirez
Phylogeny And Historical Biogeography Of The Spider Genus Lutica (Araneae, Zodariidae), Martina G. Ramirez
Biology Faculty Works
Spiders of the genus Lutica from 19 populations in southern California and Baja California, including all the California Channel Islands except Anacapa, were compared electrophoretically on the basis of variability at 15 gene loci. Fixed allelic differences clearly define two species: new species A [Santa Barbara and Ventura Counties, northern Channel Islands (San Miguel, Santa Rosa, Santa Cruz), southern Channel Islands (San Nicolas, Santa Barbara, Santa Catalina)] and new species C [Guerrero Negro, central Baja California], while morphological features define two others: new species B [Los Angeles, Orange and San Diego Counties, northern Baja California] and clementea [San Clemente Island] …
The Effect Of Fluctuating Substrate Salinity On The Yield And Flag Leaf Photosynthesis Of Wheat, Philippa M. Drennan
The Effect Of Fluctuating Substrate Salinity On The Yield And Flag Leaf Photosynthesis Of Wheat, Philippa M. Drennan
Biology Faculty Works
No abstract provided.
Leaf Anatomy, Chloroplast Organization And Photosynthetic Rate Of Hyperhydric Eucalyptus Saligna Sm. Material, Philippa M. Drennan
Leaf Anatomy, Chloroplast Organization And Photosynthetic Rate Of Hyperhydric Eucalyptus Saligna Sm. Material, Philippa M. Drennan
Biology Faculty Works
No abstract provided.
Phenotypic Assortment In Tetrahymena Thermophila: Assortment Kinetics Of Antibiotic-Resistance Markers, Tsa, Death, And The Highly Amplified Rdna Locus., E. Virginia Merriam, P.J. Bruns
Phenotypic Assortment In Tetrahymena Thermophila: Assortment Kinetics Of Antibiotic-Resistance Markers, Tsa, Death, And The Highly Amplified Rdna Locus., E. Virginia Merriam, P.J. Bruns
Biology Faculty Works
Phenotypic assortment in Tetrahymena thermophila results from random distribution of alleles during amitotic division of the macronucleus. The rate of assortment is dependent on input ratio and the number of assorting units. The assortment of the antibiotic resistance markers Chx, Mpr and gal was determined and is consistent for each with the model of 45 assorting chromosomes. The gene tsA (previously ts-1) shows normal assortment, in contrast to previous reports. A mutation in the highly amplified ribosomal locus (rdnA2) assorts as if present at only 45 copies. Death of clones occurred at a rate consistent with assortment for a single …
Physiological And Anatomical Aspects Of Photosynthesis Of Two Agrostis Species At A Sub‐Antarctic Island, Philippa M. Drennan
Physiological And Anatomical Aspects Of Photosynthesis Of Two Agrostis Species At A Sub‐Antarctic Island, Philippa M. Drennan
Biology Faculty Works
Leaf anatomy, rates of photosynthesis, leaf N, chlorophyll, RuBP carboxylase and nitrate reductase were studied on the indigenous Agrostis magellanica Lam. and the invasive alien Agrostis stolonifera L. on Marion Island (46° 54′ S, 37° 45′ E). Leaves of A. magellanica were more deeply ridged, thicker and more sclerophyllus than those of A. stolonifera. Mesophyll cells of A. magellanica were larger but the number of cells per unit leaf area and the total area of chloroplast per unit leaf area were the same for the two species. Maximum CO2 assimilation rates for the two species did not differ (mean maxima …
Nullisomic Tetrahymena. Ii. A Set Of Nullisomics Define The Germinal Chromosomes, E. Virginia Merriam
Nullisomic Tetrahymena. Ii. A Set Of Nullisomics Define The Germinal Chromosomes, E. Virginia Merriam
Biology Faculty Works
Crosses of a diploid Tetrahymena thermophila to a strain with a haploid germinal nucleus result in chromosome loss during meiosis in the haploid. The resulting monosomics can be made nullisomic by a special cross that induces homozygosis of a meiotic product of the germinal nucleus, but retention of the parental somatic nucleus. The creation and testing of single nullisomics for three of the five chromosome pairs and a triple nullisomic missing another pair is presented. Taken together, these strains make possible a series of crosses in which all but one of the chromosomes is missing in one parent. This set …
Physiology Of Salt Excretion In The Mangrove Avicennia Marina (Forsk.) Vierh, Philippa M. Drennan
Physiology Of Salt Excretion In The Mangrove Avicennia Marina (Forsk.) Vierh, Philippa M. Drennan
Biology Faculty Works
Diurnal and long‐term excretion by leaves of Avicennia marina seedlings growing in aqueous culture was correlated with substrate salinity and transpiration. Excretion was greater in 100% than 50% seawater but the reverse was true for transpiration. The diurnal excretion pattern, with exudation minimal during the day and maximal during the night, showed a negative correlation with the daily transpiration pattern. The total amount of salt excreted, however, showed a positive correlation with the total amount of water transpired. Root and xylem sap salinities were linearly related to substrate salinity but leaf Na+ increased to a maximum, indicating that control of …
Mammalian Cell Genetics I. Selection And Characterization Of Mutations Auxotrophic For L-Glutamine Or Resistant To 8-Azaguanine In Chinese Hamster Cells In Vitro, E. Virginia Merriam
Mammalian Cell Genetics I. Selection And Characterization Of Mutations Auxotrophic For L-Glutamine Or Resistant To 8-Azaguanine In Chinese Hamster Cells In Vitro, E. Virginia Merriam
Biology Faculty Works
No abstract provided.