Thermal Physiology Flashcards
Conduction
physical contact
Convection
movement of fluid across a surface
Radiation
electromagnetic radiation
Evaporation
cooling mechanism, loses water to vapour state
Regional heterothermy
increased heat generation in certain region of animal
Temporal heterothermy
increased heat generation at certain time
Exergonic reaction
releases energy
Endergonic reaction
uses energy
Ectotherm MR trends
increases w/ increasing T: biochemical reactions go faster at high temp
Endotherm MR trends
MR increases w/ decreasing T: give themselves extra metabolic work to do to maintain constant body T
Futile cycling
spin ATP cycle faster to generate more heat
Body sizes
ectotherms in high latitudes can’t be large animals
ectotherms can have smaller body sizes than endotherms
Vasodilation
increase diameter of blood vessels around skin
Plasma membranes
endotherm plasma membranes leakier to ions than ectotherm
Vasoconstriction
endotherms, keeps heat in body core to preserve vital organs
Countercurrent heat exchangers
passes heat from blood
Nonshivering thermogenesis
brown fat-uses uncoupler to use mitochondria to produce heat rather than ATP, keeps respiration going
Thermogenin
protein. uncoupler in non shivering thermogensis
Mammalian thermostat
located in hypothalamus, has adjustable setpoint, integrates info about air temp and internal body temp
Torpor
regulated hypothermia, brief inactive state that lowers thermostat’s setpoint to save energy. used by small, active endothermis. short term-daily
Wetbulb temp
temp measured by a wet cloth around bulb of a thermometer
depends on air temp and relative humidity
Max wet bulb temp
31-35C
Each 1C increase in mean global temp =
0.75 increase in wet bulb
