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Taster (genetics)
A taster is a person, by means of a human genotype, who is able to taste phenylthiocarbamide (PTC) and its derivative 6-n-propylthiouracil Propylthiouracil (PTU) is a medication used to treat hyperthyroidism. This includes hyperthyroidism due to Graves' disease and toxic multinodular goiter. In a thyrotoxic crisis it is generally more effective than methimazole. Otherwise it is t ... (PROP). PTC tastes bitter to many people (tasters) but is tasteless to others (non-tasters). About 70% of Caucasians from North America and Western Europe are tasters. The other 30% are non-tasters. Worldwide, fewer Black and Asian persons are non-tasters, and about 50% of indigenous persons from India are non-tasters. See also * PTC tasting Notes Further reading * Urea cycle Sensors Classical genetics {{genetics-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenylthiocarbamide
Phenylthiocarbamide (PTC), also known as phenylthiourea (PTU), is an organosulfur thiourea containing a phenyl ring. It has the unusual property that it either tastes very bitter or is virtually tasteless, depending on the genetic makeup of the taster. The ability to taste PTC is often treated as a dominant genetic trait, although inheritance and expression of this trait are somewhat more complex. PTC also inhibits melanogenesis and is used to grow transparent fish. About 70% of people can taste PTC, varying from a low of 58% for Indigenous Australians and indigenous peoples of New Guinea to 98% for indigenous peoples of the Americas. One study has found that non-smokers and those not habituated to coffee or tea have a statistically higher percentage of tasting PTC than the general population. PTC does not occur in food, but related chemicals do, and food choice is related to a person's ability to taste PTC. History The tested genetic taste phenomenon of PTC was discovere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propylthiouracil
Propylthiouracil (PTU) is a medication used to treat hyperthyroidism. This includes hyperthyroidism due to Graves' disease and toxic multinodular goiter. In a thyrotoxic crisis it is generally more effective than methimazole. Otherwise it is typically only used when methimazole, surgery, and radioactive iodine is not possible. It is taken by mouth. Common side effects include itchiness, hair loss, parotid swelling, vomiting, muscle pains, numbness, and headache. Other severe side effects include liver problems and low blood cell counts. Use during pregnancy may harm the baby. Propylthiouracil is in the antithyroid family of medications. It works by decreasing the amount of thyroid hormone produced by the thyroid gland and blocking the conversion of thyroxine (T4) to triiodothyronine (T3). Propylthiouracil came into medical use in the 1940s. It is on the World Health Organization's List of Essential Medicines. Side effects Propylthiouracil is generally well tolerated, with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PTC Tasting
PTC tasting is a classic genetic marker in human population genetics investigations. History In 1931 Arthur Fox, a chemist at DuPont, in Wilmington, Delaware, synthesized phenylthiocarbamide (PTC). Some researchers reported a bitter taste when entering his laboratory, while others, including Fox himself, experienced no such sensation. Further study of this phenomenon by L.H. Snyder in 1931 led to the conclusion that the inability to taste PTC is a recessive trait. In 1932, Albert Blakeslee conducted a large-scale study involving the inheritance of PTC tasting within families that concluded that PTC tasting sensitivity is very likely a complex Mendelian trait whose variance is overwhelmingly dependent on a single gene locus; however, it is likely that a few other genes have a smaller effect as well. In 1939 Fisher et al. found that the genetic frequency of PTC tasting was the same in chimps and humans. This similarity suggests that whatever gene controls for PTC tasting must have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urea Cycle
The urea cycle (also known as the ornithine cycle) is a cycle of biochemical reactions that produces urea (NH2)2CO from ammonia (NH3). Animals that use this cycle, mainly amphibians and mammals, are called ureotelic. The urea cycle converts highly toxic ammonia to urea for excretion. This cycle was the first metabolic cycle to be discovered ( Hans Krebs and Kurt Henseleit, 1932), five years before the discovery of the TCA cycle. This cycle was described in more detail later on by Ratner and Cohen. The urea cycle takes place primarily in the liver and, to a lesser extent, in the kidneys. Function Amino acid catabolism results in waste ammonia. All animals need a way to excrete this product. Most aquatic organisms, or ammonotelic organisms, excrete ammonia without converting it. Organisms that cannot easily and safely remove nitrogen as ammonia convert it to a less toxic substance, such as urea, via the urea cycle, which occurs mainly in the liver. Urea produced by the liver is th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sensors
A sensor is a device that produces an output signal for the purpose of sensing a physical phenomenon. In the broadest definition, a sensor is a device, module, machine, or subsystem that detects events or changes in its environment and sends the information to other electronics, frequently a computer processor. Sensors are always used with other electronics. Sensors are used in everyday objects such as touch-sensitive elevator buttons (tactile sensor) and lamps which dim or brighten by touching the base, and in innumerable applications of which most people are never aware. With advances in micromachinery and easy-to-use microcontroller platforms, the uses of sensors have expanded beyond the traditional fields of temperature, pressure and flow measurement, for example into MARG sensors. Analog sensors such as potentiometers and force-sensing resistors are still widely used. Their applications include manufacturing and machinery, airplanes and aerospace, cars, medicine, robot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
