Search results
Results from the WOW.Com Content Network
As in other mammals, human thermoregulation is an important aspect of homeostasis. In thermoregulation, body heat is generated mostly in the deep organs, especially the liver, brain, and heart, and in contraction of skeletal muscles. [1] Humans have been able to adapt to a great diversity of climates, including hot humid and hot arid.
Limb length affects the body's surface area, which helps with thermoregulation. Shorter limbs help to conserve heat, while longer limbs help to dissipate heat. [13] Marshall T. Newman argues that this can be observed in Eskimo, who have shorter limbs than other people and are laterally built. [14]
The best-known homeostatic mechanisms in humans and other mammals are regulators that keep the composition of the extracellular fluid (or the "internal environment") constant, especially with regard to the temperature, pH, osmolality, and the concentrations of sodium, potassium, glucose, carbon dioxide, and oxygen.
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.
The only known living homeotherms are mammals and birds, as well as one lizard, the Argentine black and white tegu. Some extinct reptiles such as ichthyosaurs, pterosaurs, plesiosaurs and some non-avian dinosaurs are believed to have been homeotherms. Tachymetabolism [c] maintains a high "resting" metabolism. In essence, tachymetabolic ...
Environmental conditions, primarily temperature and humidity, affect the ability of the mammalian body to thermoregulate. The psychrometric temperature, of which the wet-bulb temperature is the main component, largely limits thermoregulation. It was thought that a wet-bulb temperature of about 35 °C (95 °F) was the highest sustained value ...
These are known as facultative or exercise endotherms. [17] The honey bee , for example, does so by contracting antagonistic flight muscles without moving its wings (see insect thermoregulation ). [ 18 ] [ 19 ] [ 20 ] This form of thermogenesis is, however, only efficient above a certain temperature threshold, and below about 9–14 °C (48 ...
Energy intake is measured by the amount of calories consumed from food and fluids. [1] Energy intake is modulated by hunger, which is primarily regulated by the hypothalamus, [1] and choice, which is determined by the sets of brain structures that are responsible for stimulus control (i.e., operant conditioning and classical conditioning) and cognitive control of eating behavior.