Negative feedback Essay
Homeostasis of Animals and Plants
Many animals, including humans, can regulate their body temperature through a process called negative feedback. The temperature within the body is regulated to be maintained within a certain range. Animals capable of this type of homeostasis are deemed homeotherms (1). Temperature is adjusted by receptors that detect temperature fluctuations called thermoreceptors, which are found in the hypothalamus-a portion of the brain. These receptors can also be found in the skin, where they can recognize the temperature of the external environment as well (1). Once this information is attained, it is transferred to the hypothalamus. The hypothalamus can then transmit nerve pulses results in the regulating mechanisms to balance the temperature.
Temperature management in humans can be controlled in many responses, including sweating or shivering. Sweating is used when the temperature inside the body becomes too hot, usually ninety-nine degrees or higher. This mechanism is a corrective response to overheating along with vasodilation. This process is the closing of blood vessels to the skin surface and becoming more dilated. This allows the surface area to increase. By increasing the surface area, heat is lost to the external environment, cooling the body down back to normal temperature. However, shivering is the exact opposite of this response. When the body becomes too cold, the internal system works to bring it back up. This is also called Vasoconstriction. If the opposite occurs and body temperature drops, signals from the hypothalamus are sent to the cutaneous arteries (arteries supplying the skin) (2). When the body temperature of an organism drops the blood vessels become constricted in order to decrease surface area. This allows for minimal heat loss. Warmer blood is seen to be immersed in the body so to keep heat from escaping at the surface (2). In human thermal regulation, the hairs on the body aid...
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