English for

 
7.2 Reading #3:
 Neural Control of Thermoregulation 
The nervous system is important to 
thermoregulation
, as illustrated in Figure 128. The 
hypothalamus is the primary location for homeostasis and temperature regulation in the advanced 
animal brain. 
Figure 128.
In response to signals from the nervous system, the body can control its internal temperature. 
Leukocytes kill bacteria, which causes the release of pyrogens into the blood. Fever is caused by pyrogens, 
which cause the body's thermostat to be reset to a higher temperature. How could pyrogens increase body 
temperature?? 
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https://www.openstax.org/l/thermoregulate
 

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The hypothalamus regulates body temperature through reflexes that result in sweating and 
vasodilation when the body is too warm or shivering and vasoconstriction when the body is too cold. 
It responds to bodily chemicals. Endogenous pyrogens are substances that are released into the blood 
when phagocytic leukocytes kill a bacterium. The hypothalamus receives these pyrogens and the 
thermostat is reset. This enables the condition known as a fever, in which the body's temperature 
rises. A nutrient required by bacteria is reduced as a result of iron becoming more conserved as body 
temperature rises. The animal's own enzymes and defense cells become more active as its body 
temperature rises, while the enzymes and activity of the invading microorganisms become less active. 
Finally, the pathogen may also be killed by heat itself. Fever, once believed to be a side effect of an 
infection, is now recognized as a natural defense mechanism
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Key definitions 
Homeostasis 
– 
a propensity for an organism, population, or group to be in a reasonably stable equilibrium or 
condition between its many yet dependent components, or groupings of components