Portal:Biology
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Blue has been chosen as the colour for this portal to emphasise that life on Earth relies on the unique chemistry of water. A photo of Darlingtonia californica, the cobra lily, was chosen as the portal icon because of this species' dependency on a humid habitat, as well as illustrating both autotrophy (in this case, photosynthesis) and carnivory. Finally, it superficially resembles young shoots, with their tips curved in, symbolising growth, a feature of all life.
Chromatophores are pigment-containing and light-reflecting cells found in amphibians, fish, reptiles, crustaceans, and cephalopods. They are largely responsible for generating skin and eye colour in cold-blooded animals and are generated in the neural crest during embryonic development. Mature chromatophores are grouped into subclasses based on their colour (more properly "hue") under white light: xanthophores (yellow), erythrophores (red), iridophores (reflective / iridescent), leucophores (white), melanophores (black/brown) and cyanophores (blue). The term can also refer to coloured, membrane associated vesicles found in some forms of photosynthetic bacteria.
Some species can rapidly change colour through mechanisms that translocate pigment and reorient reflective plates within chromatophores. This process, often used as a type of camouflage, is called physiological colour change. Cephalopods such as octopus have complex chromatophore organs controlled by muscles to achieve this, while vertebrates such as chameleons generate a similar effect by cell signaling. Such signals can be hormones or neurotransmitters and may be initiated by changes in mood, temperature, stress or visible changes in local environment.
Unlike cold-blooded animals, mammals and birds have only one class of chromatophore-like cell type: the melanocyte. The cold-blooded equivalent, melanophores, are studied by scientists to understand human disease and used as a tool in drug discovery.
Tawfiq Canaan (24 September 1882 – 15 January 1964) was a physician and pioneer in the field of medicine in Palestine, also well-known for being one of the foremost researchers of Palestinian popular heritage.
A medical officer in the Ottoman army in World War I and the first President of the Palestine Arab Medical Association established in 1944, Canaan authored more than 37 studies over the course of his medical career on tropical medicine and bacteriology, particularly malaria, and other topics, such as leprosy, tuberculosis, and health in Palestine.
Canaan's keen interest in Palestinian folklore, popular beliefs, and superstitions led to his collection of over 1,400 amulets, now held by Bir Zeit university in Ramallah. His published analyses of these and other folk traditions brought him recognition as an ethnographer and anthropologist. A member of the Palestine Oriental Society and The American School for Oriental Research, Canaan published a number of books and more than 50 articles in English and German on folklore and superstition that have served as valuable resources to researchers of Palestinian and Middle Eastern heritage ever since.
Canaan was also a Palestinian nationalist and outspoken public figure who wrote two books on the Palestine problem, which reflected his involvement in confronting British imperialism and Zionism. Arrested by the British authorities in 1939, his family home and clinic in Jerusalem destroyed during the 1948 Arab-Israeli war, Canaan nevertheless managed to re-establish his life and career there. After taking sanctuary in a convent in the Old City with his family for two years, they eventually took up residence on the grounds of the Augusta Victoria Hospital on the Mount of Olives where Canaan served as the Director, and where they lived through his retirement until his death in 1964.
- ...that a prokaryotic cytoskeleton has been found in prokaryote organisms by recent advances in visualization technology?
- ...that the Champawat tigress and the Tsavo lions had suffered injuries that disabled them from pursuing their natural prey, leading them to become man-eaters?
- ...that the aphid Brevicoryne brassicae has been called a "walking mustard oil bomb" due to its use of glucosinolates as a chemical defense mechanism against predators?
- ...that the 1984 Rajneeshee bioterror attack was the first bioterrorism attack in the United States, and one of only two confirmed terrorist uses of biological weapons to harm humans?
- ...that Florida has over 20 official state symbols, including a state soil and a state wildflower?
- ...that Adenovirus serotype 14 is an emerging virus, related to the common cold, that has recently caused 10 deaths in the United States, including at least one healthy young adult?
- ...that three out of every seventy-seven rainbow runners (pictured) have five spines rather than the normal six?
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WikiProjects connected with biology:
- Conservation worldwide
- Ecology
- Ecoregions
- Evolutionary biology
- Genetics
- History of Science
- Marine life
- Medicine
- Microbiology
- Molecular and Cellular Biology
- Neuroscience
- Tree of Life
A complete list of scientific WikiProjects can be found here. See also Wikispecies, a Wikimedia project dedicated to classification of biological species.
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| Animals | Biotechnology | Ecology | Evolutionary biology | Extinction |
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| Marine Life | Metabolism | Molecular and Cell Biology |
Neuroscience | Plants |
