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Full-Text Articles in Biology
From Hopeful Monsters To Homeotic Effects: Richard Goldschmidt's Integration Of Development, Evolution, And Genetics, Michael Dietrich
From Hopeful Monsters To Homeotic Effects: Richard Goldschmidt's Integration Of Development, Evolution, And Genetics, Michael Dietrich
Dartmouth Scholarship
Richard Goldschmidts research on homeotic mutants from 1940 until his death in 1958 represents one of the first serious efforts to integrate genetics, development, and evolution. Using two different models, Goldschmidt tried to show how different views of genetic structure and gene action could provide a mechanism for rapid speciation. Developmental systems were emphasized in one model and a hierarchy of genetic structures in the other. While Goldschmidt tried to find a balance between development and genetics, critics, such as Sewall Wright, urged him and eventually helped him incorporate population dynamics into his models as well. As such, the history …
Fast Transport Of Neurofilament Protein Along Microtubules In Squid Axoplasm, Veena Prahlad, Brian T. Helfand, George M. Langford, Ron D. Vale, Robert D. Goldman
Fast Transport Of Neurofilament Protein Along Microtubules In Squid Axoplasm, Veena Prahlad, Brian T. Helfand, George M. Langford, Ron D. Vale, Robert D. Goldman
Dartmouth Scholarship
Using squid axoplasm as a model system, we have visualized the fast transport of non-filamentous neurofilament protein particles along axonal microtubules. This transport occurs at speeds of 0.5-1.0 microm/second and the majority of neurofilament particles stain with kinesin antibody. These observations demonstrate, for the first time, that fast (0.5-1.0 microm/second) transport of neurofilament proteins occurs along microtubules. In addition, our studies suggest that neurofilament protein can be transported as non-membrane bound, nonfilamentous subunits along axons, and that the transport is kinesin-dependent. Microtubule-based fast transport might therefore provide a mechanism for the distribution and turnover of neurofilament, and perhaps other cytoskeletal …
Direct Determination Of The Kinetics Of Oxygen Diffusion To The Photocytes Of A Bioluminescent Elaterid Larva, Measurement Of Gas- And Aqueous-Phase Diffusional Barriers And Modelling Of Oxygen Supply, G. S. Timmins, E. J. Bechara, H. M. Swartz
Direct Determination Of The Kinetics Of Oxygen Diffusion To The Photocytes Of A Bioluminescent Elaterid Larva, Measurement Of Gas- And Aqueous-Phase Diffusional Barriers And Modelling Of Oxygen Supply, G. S. Timmins, E. J. Bechara, H. M. Swartz
Dartmouth Scholarship
We describe the development and use of a direct kinetic technique to determine the time taken for oxygen to diffuse from the external environment into the light-producing cells (photocytes) in the prothorax of bioluminescent larvae of Pyrearinus termitilluminans. This was achieved by measuring the time course of the pseudoflash induced through sequential anoxia followed by normoxia. We have also determined the separate times taken for this oxygen diffusion in gaseous and tissue (predominantly aqueous) phases by using helium and nitrogen as the carrier gas. Of the total time taken for diffusion, that in the gas phase required 613+/-136 ms (mean …
The Docking Stage Of Yeast Vacuole Fusion Requires The Transfer Of Proteins From A Cis-Snare Complex To A Rab/Ypt Protein, Albert Price, Darren Seals, William Wickner, Christian Ungermann
The Docking Stage Of Yeast Vacuole Fusion Requires The Transfer Of Proteins From A Cis-Snare Complex To A Rab/Ypt Protein, Albert Price, Darren Seals, William Wickner, Christian Ungermann
Dartmouth Scholarship
The homotypic fusion of yeast vacuoles requires Sec18p (NSF)-driven priming to allow vacuole docking, but the mechanism that links priming and docking is unknown. We find that a large multisubunit protein called the Vam2/6p complex is bound to cis-paired SNAP receptors (SNAREs) on isolated vacuoles. This association of the Vam2/6p complex with the cis-SNARE complex is disrupted during priming. The Vam2/6p complex then binds to Ypt7p, a guanosine triphosphate binding protein of the Rab family, to initiate productive contact between vacuoles. Thus, cis-SNARE complexes can contain Rab/Ypt effectors, and these effectors can be mobilized by NSF/Sec18p-driven priming, allowing their direct …
Richard Goldschmidt And The Crossing-Over Controversy, Michael Dietrich, Marsha Richmond
Richard Goldschmidt And The Crossing-Over Controversy, Michael Dietrich, Marsha Richmond
Dartmouth Scholarship
This book, Perspectives on Genetics, collects more than 100 of these essays, which cumulatively are a history of modern genetics research and its continuing evolution.
The Problem Of The Gene, Michael Dietrich
The Problem Of The Gene, Michael Dietrich
Dartmouth Scholarship
During the early 20th century the diverse practices of genetics were unified by the concept of the gene. This classical gene was simultaneously a unit of structure, function, mutation, and recombination. Starting in the 1940s, however, the classical gene began to fragment. Today when we speak of a gene for some malady, a regulatory gene, a structural gene, or a gene frequency, it is entirely possible that we are deploying different gene concepts even though we are using the same term. The problem of the gene addresses the fragmentation of the classical gene concept by asking to what extent a …
From Gene To Genetic Hierarchy: Richard Goldschmidt And The Problem Of The Gene, Michael Dietrich
From Gene To Genetic Hierarchy: Richard Goldschmidt And The Problem Of The Gene, Michael Dietrich
Dartmouth Scholarship
No abstract provided.
Of Moths And Men: Theo Lang And The Persistence Of Richard Goldschmidt's Theory Of Homosexuality, 1916-1960, Michael Dietrich
Of Moths And Men: Theo Lang And The Persistence Of Richard Goldschmidt's Theory Of Homosexuality, 1916-1960, Michael Dietrich
Dartmouth Scholarship
Using an analogy between moths and men, in 1916, Richard Goldschmidt proposed that homosexuality was a case of genetic intersexuality. As he strove to create a unified theory of sex determination that would encompass animals ranging from moths to men, Goldschmidt's doubts grew concerning the association of homosexuality with intersexuality until, in 1931, he dropped homosexuality from his theory of intersexuality. Despite Goldschmidt's explicit rejection of his theory of homosexuality, Thee Lang, a researcher in the Genealogical-Demographic Department of the Institute for Psychiatric Research in Munich, revived it, maintained Goldschmidt's association with it, and argued on its behalf in publications …
Unifying Biology: Evolutionary And Molecular Biology: Science Perspectives On Divine Action, Michael Dietrich
Unifying Biology: Evolutionary And Molecular Biology: Science Perspectives On Divine Action, Michael Dietrich
Dartmouth Scholarship
Book Review of Evolutionary and Molecular Biology: Science Perspectives on Divine Action by Robert J. Russell, William R. Stoeger, SJ and Francisco J. Ayla.
An American Obsession: Science, Medicine, And Homosexuality In Modern Society, Michael Dietrich
An American Obsession: Science, Medicine, And Homosexuality In Modern Society, Michael Dietrich
Dartmouth Scholarship
Book review of An American Obsession: Science, Medicine, and Homosexuality in Modern Society by Jennifer Terry, 1999.