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Journal articles on the topic 'Variation (biology)'

Author: Grafiati

Published: 4 June 2021

Last updated: 30 July 2024

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1

Antia, Bassey E., and Richard A. Kamai. "Writing biology, assessing biology." Terminology 22, no. 2 (December 31, 2016): 201–22. http://dx.doi.org/10.1075/term.22.2.03ant.

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There has been substantial research into terminology as an issue in learning science, especially against the backdrop of concerns over school literacy in science and as sometimes reflected in the poor performance of high school students in assessment tasks. Relevant research has emphasized issues such as lexical load, complexity and metaphor. Variation in the use of terminology has, however, been relatively under researched, although there is evidence that terminology use does vary within and across high school textbooks of science. Drawing on an eclectic theoretical framework comprising transitivity analysis (Halliday 1994), legitimation code theory semantics (Maton 2013a), and the context-specific term model (Gerzymisch-Arbogast 2008), this article identifies and classifies variations in the terminology employed in three high school textbooks of biology in Nigeria. It then determines what impact assessment tasks which use terms that differ from those employed in students’ study materials have on students. Examples are found of variant terminology impeding science literacy and task performance, even though there is reason to suspect such variation might in fact have been leveraged to enhance cognition.

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2

Przytycka, Teresa M. "Phenotypic variation meets systems biology." Genome Biology 10, no. 8 (2009): 313. http://dx.doi.org/10.1186/gb-2009-10-8-313.

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3

Thompson, R. C. A., and A. J. Lymbery. "Echinococcus: Biology and strain variation." International Journal for Parasitology 20, no. 4 (July 1990): 457–70. http://dx.doi.org/10.1016/0020-7519(90)90193-q.

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4

Montévil, Maël, Matteo Mossio, Arnaud Pocheville, and Giuseppe Longo. "Theoretical principles for biology: Variation." Progress in Biophysics and Molecular Biology 122, no. 1 (October 2016): 36–50. http://dx.doi.org/10.1016/j.pbiomolbio.2016.08.005.

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5

Donelson, J. E., and A. C. Rice-Ficht. "Molecular biology of trypanosome antigenic variation." Microbiological Reviews 49, no. 2 (1985): 107–25. http://dx.doi.org/10.1128/mmbr.49.2.107-125.1985.

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6

Donelson, J. E., and A. C. Rice-Ficht. "Molecular biology of trypanosome antigenic variation." Microbiological Reviews 49, no. 2 (1985): 107–25. http://dx.doi.org/10.1128/mr.49.2.107-125.1985.

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7

Safran, Rebecca J., and Mark E. Hauber. "Evolutionary Biology: Variation Isn't Always Sexy." Current Biology 17, no. 10 (May 2007): R368—R370. http://dx.doi.org/10.1016/j.cub.2007.03.041.

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8

Furmaga, Jacek, Marek Kowalczyk, Tomasz Zapolski, Olga Furmaga, Leszek Krakowski, Grzegorz Rudzki, Andrzej Jaroszyński, and Andrzej Jakubczak. "BK Polyomavirus—Biology, Genomic Variation and Diagnosis." Viruses 13, no. 8 (July 30, 2021): 1502. http://dx.doi.org/10.3390/v13081502.

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The BK polyomavirus (BKPyV), a representative of the family Polyomaviridae, is widespread in the human population. While the virus does not cause significant clinical symptoms in immunocompetent individuals, it is activated in cases of immune deficiency, both pharmacological and pathological. Infection with the BKPyV is of particular importance in recipients of kidney transplants or HSC transplantation, in which it can lead to the loss of the transplanted kidney or to haemorrhagic cystitis, respectively. Four main genotypes of the virus are distinguished on the basis of molecular differentiation. The most common genotype worldwide is genotype I, with a frequency of about 80%, followed by genotype IV (about 15%), while genotypes II and III are isolated only sporadically. The distribution of the molecular variants of the virus is associated with the region of origin. BKPyV subtype Ia is most common in Africa, Ib-1 in Southeast Asia, and Ib-2 in Europe, while Ic is the most common variant in Northeast Asia. The development of molecular methods has enabled significant improvement not only in BKPyV diagnostics, but in monitoring the effectiveness of treatment as well. Amplification of viral DNA from urine by PCR (Polymerase Chain Reaction) and qPCR Quantitative Polymerase Chain Reaction) is a non-invasive method that can be used to confirm the presence of the genetic material of the virus and to determine the viral load. Sequencing techniques together with bioinformatics tools and databases can be used to determine variants of the virus, analyse their circulation in populations, identify relationships between them, and investigate the directions of evolution of the virus.

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9

Breslow, J. L. "Human Apolipoprotein Molecular Biology and Genetic Variation." Annual Review of Biochemistry 54, no. 1 (June 1985): 699–727. http://dx.doi.org/10.1146/annurev.bi.54.070185.003411.

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10

Lemaitre, H., V. S. Mattay, F. Sambataro, B. Verchinski, R. E. Straub, J. H. Callicott, R. Kittappa, et al. "Genetic Variation in FGF20 Modulates Hippocampal Biology." Journal of Neuroscience 30, no. 17 (April 28, 2010): 5992–97. http://dx.doi.org/10.1523/jneurosci.5773-09.2010.

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11

Leslie, Paul W., and Michael A. Little. "Human Biology and Ecology: Variation in Nature and the Nature of Variation." American Anthropologist 105, no. 1 (March 2003): 28–37. http://dx.doi.org/10.1525/aa.2003.105.1.28.

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12

Wang, Xiu-Mei, Xiangbing Yang, Lian-Sheng Zang, Zheng Wang, Chang-Chun Ruan, and Xian-Jiao Liu. "Effect of geographic variation on biology and cold tolerance of Harmonia axyridis in China." Entomologia Generalis 36, no. 3 (July 1, 2017): 239–50. http://dx.doi.org/10.1127/entomologia/2017/0441.

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13

Putman, Rory, and Werner T. Flueck. "Intraspecific variation in biology and ecology of deer: magnitude and causation." Animal Production Science 51, no. 4 (2011): 277. http://dx.doi.org/10.1071/an10168.

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It has been noted that the search for patterns in biology to assist our understanding, often leads to over-simplification. That is, we are satisfied with statements that ‘the species as a rule does this’ or, ‘males of this species do that’. But within such generalisations are masked what are often important variations from that supposed norm and in practice there is tremendous variation in morphology, physiology, social organisation and behaviour of any one species. The focus on a supposedly mean optimal phenotype has diverted attention away from variation around that mean, which is regularly regarded as a kind of ‘noise’ stemming merely from stochastic effects, and thus irrelevant to evolution. Yet it is becoming increasingly clear that this variation is by converse extremely significant and of tremendous importance both to evolutionary biologists and to managers. Such intraspecific variation (IV) may be directly due to underlying genetic differences between individuals or populations within a species, but equally may include a degree of phenotypic plasticity whether as ‘non-labile’, traits which are expressed once in an individual’s lifetime, as fixed characteristics inherited from the parents or as more labile traits which are expressed repeatedly and reversibly in a mature individual according to prevailing conditions. Recognition of the extraordinary degree of IV which may be recorded within species has important consequences for management of cervids and conservation of threatened species. We review the extent of IV in diet, in morphology, mature bodyweight, reproductive physiology, in population demography and structure (sex ratio, fecundity, frequency of reproduction) before also reviewing the striking variation to be observed in behaviour: differences between individuals or populations in ranging behaviour, migratory tendency, differences in social and sexual organisation. In each case we explore the factors which may underlie the variation observed, considering the extent to which variation described has a primarily genetic basis or is a more plastic response to more immediate social and ecological cues.

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14

Vihinen, Mauno. "Poikilosis – pervasive biological variation." F1000Research 9 (June 12, 2020): 602. http://dx.doi.org/10.12688/f1000research.24173.1.

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Biological systems are dynamic and display heterogeneity at all levels. Ubiquitous heterogeneity, here called for poikilosis, is an integral and important property of organisms and in molecules, systems and processes within them. Traditionally, heterogeneity in biology and experiments has been considered as unwanted noise, here poikilosis is shown to be the normal state. Acceptable variation ranges are called as lagom. Non-lagom, variations that are too extensive, have negative effects, which influence interconnected levels and once the variation is large enough cause a disease and can lead even to death. Poikilosis has numerous applications and consequences e.g. for how to design, analyze and report experiments, how to develop and apply prediction and modelling methods, and in diagnosis and treatment of diseases. Poikilosis-aware new and practical definitions are provided for life, death, senescence, disease, and lagom. Poikilosis is the first new unifying theory in biology since evolution and should be considered in every scientific study.

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15

Vihinen, Mauno. "Poikilosis – pervasive biological variation." F1000Research 9 (September 18, 2020): 602. http://dx.doi.org/10.12688/f1000research.24173.2.

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Biological systems are dynamic and display heterogeneity at all levels. Ubiquitous heterogeneity, here called for poikilosis, is an integral and important property of organisms and in molecules, systems and processes within them. Traditionally, heterogeneity in biology and experiments has been considered as unwanted noise, here poikilosis is shown to be the normal state. Acceptable variation ranges are called as lagom. Non-lagom, variations that are too extensive, have negative effects, which influence interconnected levels and once the variation is large enough cause a disease and can lead even to death. Poikilosis has numerous applications and consequences e.g. for how to design, analyze and report experiments, how to develop and apply prediction and modelling methods, and in diagnosis and treatment of diseases. Poikilosis-aware new and practical definitions are provided for life, death, senescence, disease, and lagom. Poikilosis is the first new unifying theory in biology since evolution and should be considered in every scientific study.

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16

Kuzma, Kori, James Stevenson, Jiachen Liu, Adam Coffman, Obi L. Griffith, Malachi Griffith, Jason Walker, Lawrence Babb, Xuelu Liu, and Alex Wagner. "21. Translating human readable variation descriptions to unique computable variations with the Variation Normalizer." Cancer Genetics 268-269 (November 2022): 7–8. http://dx.doi.org/10.1016/j.cancergen.2022.10.024.

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17

Tzellos, Stelios, and Paul Farrell. "Epstein-Barr Virus Sequence Variation—Biology and Disease." Pathogens 1, no. 2 (November 8, 2012): 156–74. http://dx.doi.org/10.3390/pathogens1020156.

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18

Hütt, Marc-Thorsten. "Understanding genetic variation - the value of systems biology." British Journal of Clinical Pharmacology 77, no. 4 (March 20, 2014): 597–605. http://dx.doi.org/10.1111/bcp.12266.

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19

Hazel, Elizabeth, Michael Prosser, and Keith Trigwell. "Variation in learning orchestration in university biology courses." International Journal of Science Education 24, no. 7 (July 2002): 737–51. http://dx.doi.org/10.1080/09500690110098886.

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20

Garshelis, D. L., and E. C. Hellgren. "Variation in Reproductive Biology of Male Black Bears." Journal of Mammalogy 75, no. 1 (February 18, 1994): 175–88. http://dx.doi.org/10.2307/1382249.

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21

Sunyaev, Shamil R., and Frederick P. Roth. "Systems biology and the analysis of genetic variation." Current Opinion in Genetics & Development 23, no. 6 (December 2013): 599–601. http://dx.doi.org/10.1016/j.gde.2013.11.010.

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22

Otremski, I., M. Katz, G. Livshits, and Z. Cohen. "Biology of aging in an Israeli population. 1. Review of literature and morphological variation analysis." Anthropologischer Anzeiger 51, no. 3 (September 2, 1993): 233–49. http://dx.doi.org/10.1127/anthranz/51/1993/233.

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23

Charlesworth, Deborah, Nicholas H. Barton, and Brian Charlesworth. "The sources of adaptive variation." Proceedings of the Royal Society B: Biological Sciences 284, no. 1855 (May 31, 2017): 20162864. http://dx.doi.org/10.1098/rspb.2016.2864.

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The role of natural selection in the evolution of adaptive phenotypes has undergone constant probing by evolutionary biologists, employing both theoretical and empirical approaches. As Darwin noted, natural selection can act together with other processes, including random changes in the frequencies of phenotypic differences that are not under strong selection, and changes in the environment, which may reflect evolutionary changes in the organisms themselves. As understanding of genetics developed after 1900, the new genetic discoveries were incorporated into evolutionary biology. The resulting general principles were summarized by Julian Huxley in his 1942 book Evolution: the modern synthesis . Here, we examine how recent advances in genetics, developmental biology and molecular biology, including epigenetics, relate to today's understanding of the evolution of adaptations. We illustrate how careful genetic studies have repeatedly shown that apparently puzzling results in a wide diversity of organisms involve processes that are consistent with neo-Darwinism. They do not support important roles in adaptation for processes such as directed mutation or the inheritance of acquired characters, and therefore no radical revision of our understanding of the mechanism of adaptive evolution is needed.

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24

Zahn, L. "Immune Variation." Science Signaling 7, no. 316 (March 11, 2014): ec69-ec69. http://dx.doi.org/10.1126/scisignal.2005253.

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25

Riddihough, G. "Exploiting Variation." Science Signaling 4, no. 154 (January 4, 2011): ec9-ec9. http://dx.doi.org/10.1126/scisignal.4154ec9.

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26

Potter, Tomos, David N. Reznick, and Tim Coulson. "Substantial intraspecific variation in energy budgets: Biology or artefact?" Functional Ecology 35, no. 8 (July 4, 2021): 1693–707. http://dx.doi.org/10.1111/1365-2435.13847.

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27

Stern, David L. "PERSPECTIVE: EVOLUTIONARY DEVELOPMENTAL BIOLOGY AND THE PROBLEM OF VARIATION." Evolution 54, no. 4 (2000): 1079. http://dx.doi.org/10.1554/0014-3820(2000)054[1079:pedbat]2.0.co;2.

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28

Stern, David L. "PERSPECTIVE: EVOLUTIONARY DEVELOPMENTAL BIOLOGY AND THE PROBLEM OF VARIATION." Evolution 54, no. 4 (August 2000): 1079–91. http://dx.doi.org/10.1111/j.0014-3820.2000.tb00544.x.

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29

Liu, Xiaoping, Yanrui Gao, Yiyi Zhang, and Xuemin Wang. "Variation in skin biology to climate in Shanghai, China." Cutaneous and Ocular Toxicology 36, no. 3 (January 11, 2017): 231–36. http://dx.doi.org/10.1080/15569527.2016.1258708.

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30

Stuhrmann, H. B. "Methods of isotopic and spin contrast variation in biology." Physica B: Condensed Matter 156-157 (January 1989): 444–51. http://dx.doi.org/10.1016/0921-4526(89)90700-x.

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31

Westneat, David F., Jonathan Wright, and Niels J. Dingemanse. "The biology hidden inside residual within-individual phenotypic variation." Biological Reviews 90, no. 3 (July 30, 2014): 729–43. http://dx.doi.org/10.1111/brv.12131.

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32

Benfey, P. N., and T. Mitchell-Olds. "From Genotype to Phenotype: Systems Biology Meets Natural Variation." Science 320, no. 5875 (April 25, 2008): 495–97. http://dx.doi.org/10.1126/science.1153716.

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33

Gasch, Audrey P., Bret A. Payseur, and John E. Pool. "The Power of Natural Variation for Model Organism Biology." Trends in Genetics 32, no. 3 (March 2016): 147–54. http://dx.doi.org/10.1016/j.tig.2015.12.003.

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34

Li, Luolan, Alireza Lorzadeh, and Martin Hirst. "Regulatory variation: an emerging vantage point for cancer biology." Wiley Interdisciplinary Reviews: Systems Biology and Medicine 6, no. 1 (November 19, 2013): 37–59. http://dx.doi.org/10.1002/wsbm.1250.

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35

Fernandes, Laísa, and Patricia Shirley Prado. "Submental Anatomical Variations: The Uniqueness of a Common Variation." Journal of Morphological Sciences 38 (2021): 100–108. http://dx.doi.org/10.51929/jms.38.19.2021.

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36

Promislow, Daniel. "OMICS IN AGING RESEARCH: FROM BIOMARKERS TO SYSTEMS BIOLOGY." Innovation in Aging 3, Supplement_1 (November 2019): S234. http://dx.doi.org/10.1093/geroni/igz038.869.

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Abstract Advances in whole genome sequencing have dramatically increased our potential to understand what shapes variation in rates of aging and age-related disease in natural populations, but we are still far from realizing this potential. Researchers have identified thousands of genetic markers associated with complex human traits. However, these markers typically explain a very small fraction of the observed variance, leaving an enormous explanatory gap between genotype and phenotype. I will present data from diverse species to illustrate the power of so-called endophenotypes—the epigenome, transcriptome, proteome, and metabolome—to bridge the genotype-phenotype gap. Using multivariate and network models that integrate genetic information with other endophenotype variation, we are closer than ever to understanding the mechanisms that account for natural variation in aging and age-related disease, and the evolutionary forces that have shaped that variation.

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37

Bedge, Kiran, and Pratima Salunkhe. "Population Genetics : A Review." International Journal of Scientific Research in Science and Technology 11, no. 2 (April 20, 2024): 746–48. http://dx.doi.org/10.32628/ijsrst24112109.

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Genetics is the study of genes and genetic variations alongwith the hereditary characteristics of an organism. Genetics is a central pillar of biology. It overlaps with other areas, such as: Agriculture, Medicine, Biotechnology. Genetics involves studying: Gene structure and function Gene variation and changes How genes affect health, appearance, and personality. Population genetics studies genetic variation within and among populations, based on the Hardy-Weinberg law, which remains constant in large populations with random mating and minimal mutation, selection, and migration.

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38

Powell, Jeffrey. "Genetic Variation in Insect Vectors: Death of Typology?" Insects 9, no. 4 (October 11, 2018): 139. http://dx.doi.org/10.3390/insects9040139.

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The issue of typological versus population thinking in biology is briefly introduced and defined. It is then emphasized how population thinking is most relevant and useful in vector biology. Three points are made: (1) Vectors, as they exist in nature, are genetically very heterogeneous. (2) Four examples of how this is relevant in vector biology research are presented: Understanding variation in vector competence, GWAS, identifying the origin of new introductions of invasive species, and resistance to inbreeding. (3) The existence of high levels of vector genetic heterogeneity can lead to failure of some approaches to vector control, e.g., use of insecticides and release of sterile males (SIT). On the other hand, vector genetic heterogeneity can be harnessed in a vector control program based on selection for refractoriness.

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39

Page, Robert B., and Matt Crook. "Investigating Causal Genetic Variation in the yellow Gene of Drosophila melanogaster as a Means of Teaching Foundational Molecular Genetic Concepts & Techniques." American Biology Teacher 84, no. 1 (January 1, 2022): 28–32. http://dx.doi.org/10.1525/abt.2022.84.1.28.

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How genetic variation influences phenotypic variation is of importance to many biological disciplines, including evolutionary biology, biomedicine, and agriculture. Nevertheless, students frequently struggle to make connections across levels of biological organization, which can make it challenging to facilitate understanding of how nucleotide variation gives rise to organismal variation. At the same time, biology students are now expected to gain early experience with cornerstone techniques from molecular biology, so that these skills can be reinforced and expanded upon. Here we describe a five-to-seven-week sequencing project that examines genetic and phenotypic variation in wild-type and yellow-bodied fruit flies and, in the process, exposes students to several foundational techniques in molecular biology. In addition, students analyze partial yellow gene sequences from PCR products using the freely available bioinformatics suite UGENE and in doing so are introduced to core bioinformatics skills. The entire project is framed around the axiom that if the yellow gene controls phenotypic differences in body color between wild-type and yellow-bodied flies, it should be possible to identify causal variation in yellow sequences from wild-type versus yellow-bodied flies. This project relies on guided inquiry and can be used in 1000- or 2000-level molecular biology courses and advanced high school laboratories.

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40

Drummond, Frank. "Reproductive Biology of Wild Blueberry (Vaccinium angustifolium Aiton)." Agriculture 9, no. 4 (March 30, 2019): 69. http://dx.doi.org/10.3390/agriculture9040069.

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Wild blueberry, Vaccinium angustifolium Aiton, is a native forest understory plant that is managed as a fruit crop. Over the past 51 years, experiments have been conducted to investigate its reproduction. A model was developed that predicts bloom to begin at 100° days (base 4.4 °C) after 1 April and to end at 500° days for a period of three to four weeks. Flower stigmas are only receptive to pollen deposition for eight to 10 days, and the rate of fruit set declines rapidly after four days. Placement of pollen upon receptive stigmas suggests that fruit set occurs with as little as a single pollen tetrad. Twelve tetrads result in 50% fruit set. Several years of exploratory fruit set field experiments show viable seeds per berry, which result from pollination with compatible genotype pollen, is associated with larger berry mass (g). Decomposition of the total variance in fruit set shows that stem variation explains 65% to 79% of total variance in the fruit set. To a lesser extent, the field, year, and clone also explain the percent fruit set variation. Variation between stems may be due to variation in the number of flowers. Fruit set tends to decrease as the flower density increases, possibly due to the limitation of pollinators.

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41

Speth, Elena Bray, Neil Shaw, Jennifer Momsen, Adam Reinagel, Paul Le, Ranya Taqieddin, and Tammy Long. "Introductory Biology Students’ Conceptual Models and Explanations of the Origin of Variation." CBE—Life Sciences Education 13, no. 3 (September 2014): 529–39. http://dx.doi.org/10.1187/cbe.14-02-0020.

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Mutation is the key molecular mechanism generating phenotypic variation, which is the basis for evolution. In an introductory biology course, we used a model-based pedagogy that enabled students to integrate their understanding of genetics and evolution within multiple case studies. We used student-generated conceptual models to assess understanding of the origin of variation. By midterm, only a small percentage of students articulated complete and accurate representations of the origin of variation in their models. Targeted feedback was offered through activities requiring students to critically evaluate peers’ models. At semester's end, a substantial proportion of students significantly improved their representation of how variation arises (though one-third still did not include mutation in their models). Students’ written explanations of the origin of variation were mostly consistent with their models, although less effective than models in conveying mechanistic reasoning. This study contributes evidence that articulating the genetic origin of variation is particularly challenging for learners and may require multiple cycles of instruction, assessment, and feedback. To support meaningful learning of the origin of variation, we advocate instruction that explicitly integrates multiple scales of biological organization, assessment that promotes and reveals mechanistic and causal reasoning, and practice with explanatory models with formative feedback.

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42

Stern, P. R. "Variation in Transit." Science Signaling 4, no. 159 (February 8, 2011): ec43-ec43. http://dx.doi.org/10.1126/scisignal.4159ec43.

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43

Vinogradov, Evgeny, Jerry D. King, Ashutosh K. Pathak, Eric T. Harvill, and Andrew Preston. "Antigenic Variation amongBordetella." Journal of Biological Chemistry 285, no. 35 (June 30, 2010): 26869–77. http://dx.doi.org/10.1074/jbc.m110.115121.

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44

Kolmer, James. "Leaf Rust of Wheat: Pathogen Biology, Variation and Host Resistance." Forests 4, no. 1 (January 16, 2013): 70–84. http://dx.doi.org/10.3390/f4010070.

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45

Busack, Stephen D., and Clarence J. McCoy. "Distribution, variation and biology of Macroprotodon cucullatus (Reptilia, Colubridae, Boiginae)." Annals of the Carnegie Museum 59, no. 4 (November 15, 1990): 261–85. http://dx.doi.org/10.5962/p.330564.

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46

Gratto, Cheri L., and Fred Cooke. "Geographic Variation in the Breeding Biology of the Semipalmated Sandpiper." Ornis Scandinavica 18, no. 3 (September 1987): 233. http://dx.doi.org/10.2307/3676772.

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47

Ellner, Lisa R., and William H. Karasov. "Latitudinal Variation in the Thermal Biology of Ornate Box Turtles." Copeia 1993, no. 2 (May 3, 1993): 447. http://dx.doi.org/10.2307/1447144.

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48

Egi, Moritoki, Rinaldo Bellomo, Edward Stachowski, Craig J. French, and Graeme K. Hart. "Circadian variation of glucose levels: Biology or timing of measurements?" Critical Care Medicine 35, no. 7 (July 2007): 1801–2. http://dx.doi.org/10.1097/01.ccm.0000269346.99094.1c.

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49

Vogelzang, Mathijs, Iwan C. van der Horst, Felix Zijlstra, and Maarten W. Nijsten. "Circadian variation of glucose levels: Biology or timing of measurements?" Critical Care Medicine 35, no. 7 (July 2007): 1800–1801. http://dx.doi.org/10.1097/01.ccm.0000269406.40845.b5.

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50

Kosina, Romuald. "Selected items of wheat variation - from palaeobotany to molecular biology." Acta Societatis Botanicorum Poloniae 68, no. 2 (2014): 129–41. http://dx.doi.org/10.5586/asbp.1999.019.

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The usefulness of data on ecotypes of wheat as well as of information about distribution of genes of hybrid necrosis for an interpretation of some questionable detections of fossil materials is emphasized. Variability of contemporary wheats is illustrated by means of morphology of lodicules, anatomical structure of caryopsis, morphology of embryo and features of epidermis of inflorescence bracts. These structures exhibit often a trend dependent on ploidy level. Discrimination of similar grains of fossil <em>Triticum compactum</em> and <em>T. sphaerococcum</em> is possible when traits of embryo are used. Wheat genomes are changed by numerous translocations and are spatially separated. This status may be detected by means of in situ hybridization of the genomic DNA. With such a spatial arrangement of the genomes the dominance of a caryopsis trait complex in hybrids between tetraploid wheats may be correlated. It may also create a part of new variation in wheat.

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