Chapter 9: Internal Regulation Flashcards
Temperature Regulation
Need regulatory mechanisms to survive
Temperature Regulation
Compare to space heater…
○ Need system variable (body temperature)
Temperature Regulation
○ Set point (temperature setting)
Temperature Regulation
○ Detector (thermostat)
Temperature Regulation
○ Correcting mechanism (warming, cooling)
Homeostasis
body variable kept within a fixed range (set point)
Allostasis
set point changes in response to “life” or the environment
○ Menopause
Poikilotherms
lack internal mechanisms of temperature regulation
○ Amphibians, reptiles, most fist (one mammal= mole rat)
○ “Cold-blooded”
○ Temperature constant via behavioral measures
Homeotherm
an internal mechanism to maintain a nearly constant body temperature
○ Requires lots of energy and fuel
What decreases temperature?
Sweating and panting
Homeotherm
How to increase body temperature?
Shivering, piloerection (goosebumps),
increasing metabolic rate, decreasing blood flow to skin
Homeotherm
Mammals evolved to keep constant temperature
at 36-41 degrees C (97-105 F)
Mammals
Close to what reptile seeks under lamp
○ ⅔ of total energy spent is just on body temperature
Mammals
■ Eat a lot= way more mitochondria in our cells metabolizing fat/sugar=heat
Mammals
■ Small homeotherms are hours from death due to body mass ratios
