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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

Norbert Freinkel (1926–1989)

During the twentieth century, Norbert Freinkel studied hormones and diabetes in the US. Freinkel conducted many experiments that enabled him to determine the factors that influence hormones of the thyroid gland to bind to proteins and to determine the effects that those thyroid hormones have on surrounding tissues. Furthermore, Freinkel researched gestational diabetes, which is diabetes that occurs for the first time during a women’s pregnancy. That type of diabetes is caused by a change in the way a woman’s body responds to insulin, a hormone made in the body.

Format: Articles

Subject: People

Karl Oskar Illmensee (1939–)

Karl Oskar Illmensee studied the cloning and reproduction of fruit flies, mice, and humans in the US and Europe during the twentieth and twenty-first centuries. Illmensee used nuclear transfer techniques (cloning) to create early mouse embryos from adult mouse cells, a technique biologists used in later decades to help explain how embryonic cells function during development. In the early 1980s, Illmensee faced accusations of fraud when others were unable to replicate the results of his experiments with cloned mouse embryos.

Format: Articles

Subject: People, People

Annie Wood Besant (1847–1933)

Annie Wood Besant was a social activist who advocated for women’s access to birth control as well as marriage reform, labor reform, and Indian Nationalism in the nineteenth century in England and India. In her early career, Besant was involved in various social and political advocacy organizations including the National Secular Society, the Malthusian League, and the Fabian Society. Besant gave many public lectures and authored various articles in support of secularism, workers’ rights and unionization, and women’s rights.

Format: Articles

Subject: People

Georges Cuvier (1769-1832)

Georges Cuvier, baptized Georges Jean-Leopold Nicolas-Frederic Cuvier, was a professor of anatomy at the National Museum of Natural History in Paris, France, through the late eighteenth and early nineteenth centuries. Scholars recognize Cuvier as a founder of modern comparative anatomy, and as an important contributor to vertebrate paleontology and geology. Cuvier studied the form and function of animal anatomy, writing four volumes on quadruped fossils and co-writing eleven volumes on the natural history of fish with Achille Valenciennes.

Format: Articles

Subject: People

Allan Charles Wilson (1934-1991)

Allan C. Wilson studied genes, proteins, and body structures of animals and humans in the US during the second half of the twentieth century. Wilson also studied human evolution. Although morphology and behaviors of humans (Homo sapiens) and great apes differ, Wilson found that they have biochemical and genetic similarities. Wilson and his colleagues calculated the time period of humans' and African apes' common ancestor.

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Subject: People

Josef Warkany (1902–1992)

Josef Warkany studied the environmental causes of birth defects in the United States in the twentieth century. Warkany was one of the first researchers to show that factors in the environment could cause birth defects, and he helped to develop guidelines for the field of teratology, the study of birth defects. Prior to Warkany’s work, scientists struggled to explain if or how environmental agents could cause birth defects. Warkany demonstrated that a deficiency or excess of vitamin A in maternal nutrition could cause birth defects.

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

Ephraim McDowell (1771-1830)

Ephraim McDowell was an US abdominal surgeon who in 1809 performed one of the first successful ovarian surgeries. McDowell conducted his medical practice in Danville, Kentucky, where he used novel methods of ovariotomy to remove a twenty-two and a half pound ovarian tumor from his patient, Jane Crawford. At the time, surgeons performed ovariotomies by making an incision into each patient’s ovary to remove a mass. However, their patients often died from infection or blood loss.

Format: Articles

Subject: People

Boris Ephrussi (1901-1979)

Boris Ephrussi studied fruit flies, yeast, and mouse genetics and development while working in France and the US during the twentieth century. In yeast, Ephrussi studied how mutations in the cytoplasm persisted across generations. In mice he studied the genetics of hybrids and the development of cancer. Working with George Wells Beadle on the causes of different eye colors in fruit flies, Ephrussi's research helped establish the one-gene-one-enzyme hypothesis. Ephrussi helped create new embryological techniques and contributed the theories of genetics and development.

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Subject: People

Caspar Friedrich Wolff (1734-1794)

Caspar Friedrich Wolff is most famous for his 1759 doctoral dissertation, Theoria Generationis, in which he described embryonic development in both plants and animals as a process involving layers of cells, thereby refuting the accepted theory of preformation: the idea that organisms develop as a result of the unfolding of form that is somehow present from the outset, as in a homunculus. This work generated a great deal of controversy and discussion at the time of its publication but was an integral move in the reemergence and acceptance of the theory of epigenesis.

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Subject: People

Santiago Felipe Ramon y Cajal (1852-1934)

Santiago Felipe Ramon y Cajal investigated brains in the nineteenth and twentieth centuries in Spain. He identified and individuated many components of the brain, including the neuron and the axon. He used chick embryos instead of adult animals, then customary in brain research, to study the development and physiology of the cerebellum, spinal cord, and retina. Ramon y Cajal received the Nobel Prize in Physiology and Medicine in 1906, along with Camillo Golgi, for his work on the structure of the nervous system.

Format: Articles

Subject: People

Kurt Benirschke (1924-)

Kurt Benirschke studied cells, placentas, and endangered species in Germany and the US during the twentieth century. Benirschke was professor at the University of California in San Diego, California, and a director of the research department at the San Diego Zoo in San Diego, California. He also helped form the research department of the San Diego Zoo and its sister organization, the Center for Reproduction of Endangered Species.

Format: Articles

Subject: People

Curt Jacob Stern (1902-1981)

Curt Jacob Stern studied radiation and chromosomes in humans and fruit flies in the United States during the twentieth century. He researched the mechanisms of inheritance and of mitosis, or the process in which the chromosomes in the nucleus of a single cell, called the parent cell, split into identical sets and yield two cells, called daughter cells. Stern worked on the Drosophila melanogaster fruit fly, and he provided early evidence that chromosomes exchange genetic material during cellular reproduction.

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Subject: People

William Stewart Halsted (1852-1922)

William Stewart Halsted was a surgeon at Johns Hopkins Hospital in Baltimore, Maryland, during the late 1800s and early 1900s. In 1894 Halsted described his procedure for treating breast cancer by removing the breast tissue, chest muscles, and lymph nodes in the armpit, a procedure he named radical mastectomy, and that became the standard of care for treating breast cancer until 1970.

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Subject: People

John D. Gearhart

John D. Gearhart is a renowned American developmental geneticist best known for leading the Johns Hopkins University research team that first identified and isolated human pluripotent stem cells from human primordial germ cells, the precursors of fully differentiated germ cells. Born in Western Pennsylvania, Gearhart lived on the family farm located in the Allegheny Mountains for the first six years of his life.

Format: Articles

Subject: People

James Alexander Thomson (1958- )

James Alexander Thomson, affectionately known as Jamie Thomson, is an American developmental biologist whose pioneering work in isolating and culturing non-human primate and human embryonic stem cells has made him one of the most prominent scientists in stem cell research. While growing up in Oak Park, Illinois, Thomson's rocket-scientist uncle inspired him to pursue science as a career. Born on 20 December 1958, Thomson entered the nearby University of Illinois Urbana-Champaign nineteen years later as a National Merit Scholar majoring in biophysics.

Format: Articles

Subject: People

Calvin Blackman Bridges (1889-1938)

Calvin Blackman Bridges studied chromosomes and heredity in the US throughout the early twentieth century. Bridges performed research with Thomas Hunt Morgan at Columbia University in New York City, New York, and at the California Institute of Technology in Pasadena, California. Bridges and Morgan studied heredity in Drosophila, the common fruit fly. Throughout the early twentieth century, researchers were gathering evidence that genes, or what Gregor Mendel had called the factors that control heredity, are located on chromosomes.

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Subject: People

Leo Loeb (1869-1959)

Leo Loeb developed an experimental approach to studying cancer and pioneered techniques for tissue culture and in vitro tissue transplantation which impacted early-to-mid twentieth century experimental embryology. Loeb received his medical degree from the University of Zurich in 1897. As part of his doctorate, he completed a thesis on the outcomes of tissue transplantation in guinea pigs. Loeb's thesis inspired a life-long interest in tissue transplantation.

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Subject: People

Franklin Paine Mall (1862-1917)

Franklin Paine Mall was born into a farming family in Belle Plaine, Iowa, on 28 September 1862. While he attended a local academy, an influential teacher fueled Mall's interest in science. From 1880-1883, he studied medicine at the University of Michigan, attaining his MD degree in 1883. William J. Mayo, who later became a famous surgeon and co-founder of the Mayo Clinic in Rochester, Minnesota, was a classmate of Mall's. Throughout his studies at Michigan, he was influenced by Corydon L. Ford, a professor of anatomy, Victor C.

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Subject: People

Brian K. Hall (1941- )

Brian Hall is the son of Doris Garrad and Harry Hall, and was born in Port Kembla, NSW Australia, on 28 October 1941. He attended the University of New England in Armidale NSW, graduating in 1963 with a BSc in zoology, in 1965 with a BSc (Honors) in zoology, and in 1968 with a PhD in zoology. His PhD thesis, undertaken under the supervision of Patrick D. F. Murray, FAA was on the differentiation of bone and secondary cartilage in chicken embryos.

Format: Articles

Subject: People

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.

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Subject: People

Ricardo Hector Asch (1947- )

Ricardo Hector Asch was born 26 October 1947 in Buenos Aires, Argentina, to a lawyer and French professor, Bertha, and a doctor and professor of surgery, Miguel. Asch's middle-class family lived among the largest Jewish community in Latin America, where a majority of males were professionals. After his graduation from National College No. 3 Mariano Moreno in Buenos Aires, Asch worked as a teaching assistant in human reproduction and embryology at the University of Buenos Aires School of Medicine where he received his medical degree in 1971.

Format: Articles

Subject: Ethics, People

Leo Kanner (1894-1981)

Leo Kanner studied and described early infantile autism in humans in the US during the twentieth century. Though Eugen Bleuler first coined the term autism in 1910 as a symptom of schizophrenia, Kanner helped define autism as a disease concept separate from schizophrenia. He helped found an early child psychiatry department in 1930 at the Johns Hopkins University Hospital in Baltimore, Maryland.

Format: Articles

Subject: People

Eric Wieschaus (1947- )

Eric Wieschaus studied how genes cause fruit fly larvae to develop in the US and Europe during the twentieth and twenty-first centuries. Using the fruit fly Drosophila melanogaster, Wieschaus and colleague Christiane Nusslein-Volhard described genes and gene products that help form the fruit fly body plan and establish the larval segments during embryogenesis. This work earned Wieschaus and Nüsslein-Volhard the 1995 Nobel Prize in Physiology or Medicine.

Format: Articles

Subject: People