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Displaying 976 - 1000 of 1026 items.

Walter Jakob Gehring (1939-2014)

Walter Jakob Gehring discovered the homeobox, a DNA segment found in a specific cluster of genes that determine the body plan of animals, plants, and fungi. Gehring identified the homeobox in 1983, with the help of colleagues while isolating the Antennapedia (Antp) gene in fruit flies (Drosophila) at the University of Basel in Basel, Switzerland. Hox genes, a family of genes that have the homeobox, determine the head-to-tail (anterior-posterior) body axis of both vertebrates and invertebrates.

Format: Articles

Subject: People

Edwin Stephen Goodrich (1868-1946)

Edwin Stephen Goodrich studied the structures of animals in England during the nineteenth and twentieth centuries. Goodrich studied how animals develop to identify their parts and to establish the evolutionary relationships between different species. Goodrich established that body structures can shift their positions relative to an organism's body during evolution, and he hypothesized that body structures can share ancestry (homology) between organisms of different species, even without identical body placement.

Format: Articles

Subject: People

A plant genetically modified that accumulates Pb is especially promising for phytoremediation (2003), by Carmina Gisbert et al.

In 2003, Carmina Gisbert and her research team produced a tobacco plant that could remove lead from soil. To do so, they inserted a gene from wheat plants that produces phytochelatin synthase into a shrub tobacco plant (Nicotiana glauca) to increase N. glauca's absorption and tolerance of toxic metals, particularly lead and cadmium. Gisbert and her team aimed to genetically modify a plant so that it could be used for phytoremediation- using plants to remove toxic substances from the soil.

Format: Articles

Subject: Experiments, Technologies

Paul Kammerer's Experiments on Salamanders (1903-1912)

In the early twentieth century, Paul Kammerer conducted a series of experiments to demonstrate that organisms could transmit characteristics acquired in their lifetimes to their offspring. In his 1809 publication, zoologist Jean-Baptiste Lamarck had hypothesized that living beings can inherit features their parents or ancestors acquired throughout life. By breeding salamanders, as well as frogs and other organisms, Kammerer tested Lamarck's hypothesis in an attempt to provide evidence for Lamarck's theory of the inheritance of acquired characteristics.

Format: Articles

Subject: Experiments

Paul Kammerer's Experiments on the Midwife Toad (1905-1910)

In the first decade of the twentieth century, Paul Kammerer, a zoologist working at the Vivarium in Vienna, Austria, conducted research on developmental mechanisms, including a series of breeding experiments on toads (Alytes obstetricans). Kammerer claimed that his results demonstrated that organisms could transmit acquired characteristics to their offspring.

Format: Articles

Subject: Experiments

Organic Seed Growers and Trade Association's suit against Monsanto, 2012 and 2013

In March 2011 the Organic Seed Growers and Trade Association and around sixty agricultural organizations (OSGATA et al.) filed a suit against Monsanto Company and Monsanto Technology L.L.C., collectively called Monsanto. The hearings for Organic Seed Growers and Trade Association (OSGATA) et al. v. Monsanto (2012) took place at the United States District Court for the Southern District of New York in Manhattan, New York. The district court's Judge Naomi Reice Buchwald dismissed OSGATA's suit.

Format: Articles

Subject: Legal

Mesoderm

Mesoderm is one of the three germ layers, groups of cells that interact early during the embryonic life of animals and from which organs and tissues form. As organs form, a process called organogenesis, mesoderm interacts with endoderm and ectoderm to give rise to the digestive tract, the heart and skeletal muscles, red blood cells, and the tubules of the kidneys, as well as a type of connective tissue called mesenchyme. All animals that have only one plane of symmetry through the body, called bilateral symmetry, form three germ layers.

Format: Articles

Subject: Processes

The Germ-Plasm: a Theory of Heredity (1893), by August Weismann

Friedrich Leopold August Weismann published Das
Keimplasma: eine Theorie der Vererbung (The Germ-Plasm: a
Theory of Heredity, hereafter The Germ-Plasm) while
working at the University of Freiburg in Freiburg, Germany in 1892.
William N. Parker, a professor in the University College of South
Wales and Monmouthshire in Cardiff, UK, translated The
Germ-Plasm into English in 1893. In The Germ-Plasm,
Weismann proposed a theory of heredity based on the concept of the

Format: Articles

Subject: Publications, Theories

Paul Kammerer's Experiments on Sea-squirts in the Early Twentieth Century

In the early twentieth century, Paul Kammerer, a zoologist working at the Vivarium in Vienna, Austria, experimented on sea-squirts (Ciona intestinalis). Kammerer claimed that results from his experiments demonstrated that organisms could transmit characteristics that they had acquired in their lifetimes to their offspring. Kammerer conducted breeding experiments on sea-squirts and other organisms at a time when Charles Darwin's 1859 theory of evolution lacked evidence to explain how offspring inherited traits from their parents.

Format: Articles

Subject: Experiments, Organisms

Digit Regeneration Is Regulated by Msx1 and BMP4 in Fetal Mice (2003), by Manjong Han et al.

In the early 2000s, Manjong Han, Xiaodang Yang, Jennifer Farrington, and Ken Muneoka investigated how genes and proteins in fetal mice (Mus musculus) influenced those fetal mice to regenerate severed toes at Tulane University in New Orleans, Louisiana. The group used hind limbs from mice to show how the gene Msx1 (Homeobox 7) functions in regenerating amputated digits.

Format: Articles

Subject: Experiments

Roy Chapman Andrews (1884-1960)

Roy Chapman Andrews traveled the world studying fossils, from mammals to dinosaurs, during the first half of the twentieth century. Andrews worked and collected fossil specimens for the American Museum of Natural History (AMNH) in New York City, New York. Throughout his career, Andrews collected bones of many animal species, including a previously unknown species of a horned, herbivorous dinosaur, later named Proceratops andrewsi in his honor. Andrews published widely read narratives about his travels and field experiences, such as On the Trail of Ancient Man and Across Mongolian Plains.

Format: Articles

Subject: People

Spemann-Mangold Organizer

The Spemann-Mangold organizer, also known as the Spemann organizer, is a cluster of cells in the developing embryo of an amphibian that induces development of the central nervous system. Hilde Mangold was a PhD candidate who conducted the organizer experiment in 1921 under the direction of her graduate advisor, Hans Spemann, at the University of Freiburg in Freiburg, German. The discovery of the Spemann-Mangold organizer introduced the concept of induction in embryonic development.

Format: Articles

Subject: Processes

The Southern Gastric-Brooding Frog

The Southern Gastric-Brooding Frog (Rheobatrachus silus) was an aquatic frog that lived in south-east Australia. In 2002, the International Union for Conservation of Nature Red List declared the frog extinct, although no wild specimens had been reported since 1981. As the common name alludes to, the R.

Format: Articles

Subject: Organisms

Organisers and Genes (1940), by Conrad Hal Waddington

Conrad Hal Waddington's Organisers and Genes, published in 1940, is a summary of available research and theoretical framework for many concepts related to tissue differentiation in the developing embryo. The book is composed of two main conceptual sections. The first section explores the action and nature of the organizer, while the second section delves into genes and their influence on development.

Format: Articles

Subject: Publications

Francesco Redi (1626-1698)

Francesco Redi, son of Florentine physician Cecilia de' Ghinci and Gregorio Redi, was born in Arezzo, Italy, on 18 February 1626. He studied philosophy and medicine at the University of Pisa, graduating on 1 May 1647. A year later, Redi moved to Florence and registered at the Collegio Medico. There he served at the Medici Court as both the head physician and superintendent of the ducal pharmacy and foundry. Redi was also a member of the Accademia del Cimento, which flourished from 1657-1667. It was during this decade that Redi produced his most important works.

Format: Articles

Subject: People

Min Chueh Chang (1908-1991)

As one of the researchers involved in the development of the oral contraceptive pill, Min Chueh Chang helped to revolutionize the birth control movement. Although best known for his involvement with "the pill," Chang also made a number of discoveries throughout his scientific career involving a range of topics within the field of reproductive biology. He published nearly 350 articles in scientific journals.

Format: Articles

Subject: People, Reproduction

Wolbachia

Bacteria of the genus Wolbachia are
bacteria that live within the cells of their hosts. They infect a
wide range of arthropods (insects, arachnids, and crustaceans) and
some nematodes (parasitic roundworms). Scientists estimate that
Wolbachia exist in between seventeen percent and seventy-six percent of
arthropods and nematodes. The frequency of the bacteria makes them
one of the most widespread parasites. In general, they are divided
into five groups, from A to E, depending of the species of their

Format: Articles

Subject: Organisms

Robert Lanza (1956- )

During the twentieth and twenty-first centuries, Robert Paul Lanza studied embryonic stem cells, tissues,
and endangered species as chief scientific officer of Advanced Cell
Technology, Incorporated in Worcester, Massachusetts. Lanza's team cloned
the endangered species of gaur Bos gaurus.
Although the gaur did not survive long, Lanza successfully cloned
another cow-like creature, called the banteng
(Bos
javanicus). Lanza also worked on cloning human embryos
to harvest stem cells, which could be used to treat dieases. While

Format: Articles

Subject: People

The Genetic Control and Cytoplasmic Expression of 'Inducibility' in the synthesis of B-galactosidase" (1959), by Arthur B. Pardee, Francois Jacob, and Jacques Monod

Between 1957 and 1959, Arthur Pardee, Francois Jacob, and Jacques Monod conducted a set of experiments at the Pasteur Institute in Paris, France, that was later called the PaJaMa Experiments, a moniker derived from the researchers' last names. In these experiments, they described how genes of a species of single-celled bacteria, called Escherichia coli (E. coli), controlled the processes by which enzymes were produced in those bacteria.

Format: Articles

Subject: Experiments

The Y-Chromosome in Animals

The Y-chromosome is one of a pair of chromosomes that determine the genetic sex of individuals in mammals, some insects, and some plants. In the nineteenth and twentieth centuries, the development of new microscopic and molecular techniques, including DNA sequencing, enabled scientists to confirm the hypothesis that chromosomes determine the sex of developing organisms. In an adult organism, the genes on the Y-chromosome help produce the male gamete, the sperm cell. Beginning in the 1980s, many studies of human populations used the Y-chromosome gene sequences to trace paternal lineages.

Format: Articles

Subject: Reproduction, Theories

Martin Couney and Incubator Exhibits from 1896 to 1943

During the late 1800s and early 1900s, physician Martin Couney held incubator exhibits to demonstrate the efficacy of infant incubators throughout the US and
Europe. At his exhibits, Couney demonstrated that isolating premature infants in an incubator ward
could significantly decrease premature infant mortality and increased the use of incubators in the
US.

Format: Articles

Subject: Organizations, Places

Irving Freiler Stein Sr. (1887–1976)

Irving Freiler Stein Sr. was a physician who studied women’s reproductive health during the twentieth century in the United States. In partnership with his colleague, Michael Leventhal, Stein identified a women’s reproductive disorder related to elevated male sex hormones, or androgens. The syndrome was originally called Stein-Leventhal syndrome and later known as polycystic ovarian syndrome. While studying the syndrome, Stein also helped establish a treatment for the condition, through the surgical removal of ovarian tissues.

Format: Articles

Subject: People

Roe v. Wade (1973)

In the 1973 case of Roe v. Wade, the US Supreme Court ruled that laws banning abortion violated the US Constitution. The Texas abortion laws, articles 1191–1194, and 1196 of the Texas penal code, made abortion illegal and criminalized those who performed or facilitated the procedure. Prior to Roe v. Wade, most states heavily regulated or banned abortions. The US Supreme Court decision in Roe v. Wade secured women's rights to terminate pregnancies for any reasons within the first trimester of pregnancy.

Format: Articles

Subject: Legal, Reproduction