temperature regulation

• Poikilothermic animals lack physiological mechanisms for temperature regulation like shivering and sweating
• Allostasis


  The adaptive way in which the body changes its set points depending on the situation
• Set Point


  A single value that the body works to maintain within a narrow range
• Preoptic Area/Anterior Hypothalamus (POA/AH)


  Plays a crucial role in regulating body temperature by monitoring its own temperature and controlling physiological mechanisms like shivering, sweating, and changes in blood flow to the skin
• Receptors for a specific kind of prostaglandin in the hypothalamus are crucial for fever development, as evidenced by individuals with mutations lacking these receptors
• Negative feedback


  Processes that reduce discrepancies from the set point
• Controlling Body Temperature


  Basal Metabolism is the energy used to maintain a constant body temperature while at rest
• Much of motivated behavior can be described as negative feedback: Something causes a disturbance, and behavior proceeds until it relieves the disturbance
• Physiologist Walter B. Cannon (1929): 'introduced the term Homeostasis, referring to temperature regulation and other biological processes that keep body variables within a fixed range'
• Poikilothermic


  Refers to animals like amphibians, reptiles, and most fish whose body temperature matches the temperature of their environment
• The POA/AH receives input from temperature receptors in the skin and spinal cord
• Despite being colloquially referred to as "cold-blooded," poikilothermic animals remain warm throughout the day by selecting suitable locations for warmth
• Leukocytes release cytokines to combat intruders, stimulating the vagus nerve to increase prostaglandin release in the hypothalamus, which in turn sets a higher body temperature point
• Homeothermic


  Refers to mammals and birds who maintain a relatively constant body temperature through physiological mechanisms, regardless of environmental temperature fluctuations