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Displaying 126 - 150 of 280 items.

Johann Gregor Mendel (1822-1884)

Johann Gregor Mendel studied plants and their patterns of inheritance in Austria during the nineteenth century. Mendel experimented with the pea plant, Pisum, and his publication, 'Versuche uber Pflanzenhybriden' (“Experiments on Plant Hybridization”), published in 1866, revolutionized theories of trait inheritance. Mendel’s discoveries relating to factors, traits, and how they pass between generations of organisms enabled scientists in the twentieth century to build theories of genetics.

Format: Articles

Subject: People

Leon Richard Kass (1939- )

A PhD and medical doctor turned ethicist, Leon Kass calls himself an unlicensed humanist. Throughout his unique career he has sought to impact others and engage important cultural issues. This he has accomplished over the course of many years by studying biochemistry, teaching humanities, writing articles and books on ethics, and serving as chair of the President's Council on Bioethics.

Format: Articles

Subject: People, Ethics, Reproduction

Christiane Nusslein-Volhard (1942- )

Christiane Nusslein-Volhard studied how genes control embryonic development in flies and in fish in Europe during the twentieth and twenty-first centuries. In the 1970s, Nusslein-Volhard focused her career on studying the genetic control of development in the fruit fly Drosophila melanogaster. In 1988, Nusslein-Volhard identified the first described morphogen, a protein coded by the gene bicoid in flies. In 1995, along with Eric F. Wieschaus and Edward B.

Format: Articles

Subject: People

John Bertrand Gurdon (1933- )

Sir John Bertrand Gurdon further developed nuclear transplantation, the technique used to clone organisms and to create stem cells, while working in Britain in the second half of the twentieth century. Gurdon's research built on the work of Thomas King and Robert Briggs in the United States, who in 1952 published findings that indicated that scientists could take a nucleus from an early embryonic cell and successfully transfer it into an unfertilized and enucleated egg cell.

Format: Articles

Subject: People

George Linius Streeter (1873-1948)

George Linius Streeter was born on 12 January 1873 in Johnstown, New York, to Hannah Green Anthony and George Austin Streeter. He completed his undergraduate studies at Union College in 1895 and received his MD degree from the College of Physicians and Surgeons of Columbia University in 1899. At Columbia, Professor George S. Huntington sparked Streeter's interest in anatomy, and Streeter also interned at Roosevelt Hospital in New York City. He then went on to Albany to teach anatomy at the Albany Medical College and to work with neurologist Henry Hun.

Format: Articles

Subject: People

Paul Kammerer (1880-1926)

Paul Kammerer conducted experiments on amphibians and marine animals at the Vivarium, a research institute in Vienna, Austria, in the early twentieth century. Kammerer bred organisms in captivity, and he induced them to develop particular adaptations, which Kammerer claimed the organismss offspring would inherit. Kammerer argued that his results demonstrated the inheritance of acquired characteristics, or Lamarckian inheritance. The Lamarckian theory of inheritance posits that individuals transmit acquired traits to their offspring.

Format: Articles

Subject: Experiments, People

Franz Julius Keibel (1861-1929)

Franz Keibel studied the embryos of humans and other animals in Europe at the turn of the twentieth century. He lived and worked in several different parts of Germany and France. Keibel drew illustrations of embryos in many stages of development. Keibel used these illustrations, which he and others in the scientific community called normal plates, to describe the development of organisms in several species of vertebrates.

Format: Articles

Subject: People

Charles Benedict Davenport (1866-1944)

Charles Benedict Davenport was an early twentieth-century experimental zoologist. Davenport founded both the Station for Experimental Evolution and the Eugenics Record Office at Cold Spring Harbor in New York. Though he was a talented statistician and skilled scientist, Davenport's scientific achievements are eclipsed by his lasting legacy as the scientific leader of the eugenics movement in the US.

Format: Articles

Subject: People, Reproduction

Carl Richard Moore (1892-1955)

Carl Richard Moore was a professor and researcher at the University of Chicago in Chicago, Illinois who studied sex hormones in animals from 1916 until his death in 1955. Moore focused on the role of hormones on sex differentiation in offspring, the optimal conditions for sperm production, and the effects of vasectomy or testicular implants on male sex hormone production. Moore's experiments to create hermaphrodites in the laboratory contributed to the theory of a feedback loop between the pituitary and fetal gonadal hormones to control sex differentiation.

Format: Articles

Subject: People

Friedrich Tiedemann (1781-1861)

Friedrich Tiedemann studied the anatomy of humans and animals in the nineteenth century in Germany. He published on zoological subjects, on the heart of fish, the anatomy of amphibians and echinoderms, and the lymphatic and respiratory system in birds. In addition to his zoological anatomy, Tiedemann, working with the chemist Leopold Gmelin, published about how the digestive system functioned.

Format: Articles

Subject: People

Edmund Beecher Wilson (1856-1939)

Edmund Beecher Wilson contributed to cell biology, the study of cells, in the US during the end of the nineteenth and the beginning of the twentieth centuries. His three editions of The Cell in Development and Inheritance (or Heredity) in 1896, 1900, and 1925 introduced generations of students to cell biology. In The Cell, Wilson described the evidence and theories of his time about cells and identified topics for future study. He helped show how each part of the cell works during cell division and in every step of early development of an organism.

Format: Articles

Subject: People