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In biochemistry, denaturation is a process in which proteins or nucleic acids lose folded structure present in their native state due to various factors, including application of some external stress or compound, such as a strong acid or base, a concentrated inorganic salt, an organic solvent (e.g., alcohol or chloroform), agitation and radiation, or heat. [3]
Adjusting the human body temperature downward has been used therapeutically, in particular, as a method of stabilizing a body following trauma. It has been suggested that adjusting the adenosine A1 receptor of the hypothalamus may allow humans to enter a hibernation -like state of reduced body temperature, which could be useful for applications ...
Unrelated enzymes that have the same enzymatic activity have been called non-homologous isofunctional enzymes. [24] Horizontal gene transfer may spread these genes to unrelated species, especially bacteria where they can replace endogenous genes of the same function, leading to hon-homologous gene displacement.
The body temperatures of many small birds (e.g. hummingbirds) and small mammals (e.g. tenrecs) fall dramatically during daily inactivity, such as nightly in diurnal animals or during the day in nocturnal animals, thus reducing the energy cost of maintaining body temperature. Less drastic intermittent reduction in body temperature also occurs in ...
The human body has two methods of thermogenesis, which produces heat to raise the core body temperature. The first is shivering, which occurs in an unclothed person when the ambient air temperature is under 25 °C (77 °F) [dubious – discuss]. [18] It is limited by the amount of glycogen available in the body. [5]
Hence, if the body were perfectly insulated, core temperature would continue to increase until lethal core temperatures were achieved. Conversely, we are normally in surroundings that are considerably cooler than the body's core temperature of 37 °C (98.6 °F) creating a gradient for thermal energy flow from the core to the surroundings.
In 1847, Carl Bergmann published his observations that endothermic body size (i.e. mammals) increased with increasing latitude, commonly known as Bergmann's rule. [9] His rule postulated that selection favored within species individuals with larger body sizes in cooler temperatures because the total heat loss would be diminished through lower surface area to volume ratios. [8]
Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different. A thermoconforming organism, by contrast, simply adopts the surrounding temperature as its own body temperature, thus avoiding the need for internal thermoregulation.