Physiology 7: Body temp Flashcards
What happens if body temp is too low?
Too low
- Slow metabolism
Inadequate O2 supply (molecules have less kinetic energy, lower O2 affinity)
Freezing of cells
What happens if body temp is too high?
Too high
Proteins denature
Inadequate O2 supply (metabolic rate increases, tissue O2 requirement increases)
Membrane structure alterations
= geographical ranges of animals would be restricted to temp favourable regions
What are the 4 heat exchange processes?
Radiation
Convection
Conduction
Evaporation
Describe radiation
Without direct contact
In humans, 60% heat loss
E.g from the sun
Describe convection
Air/fluid across body surface
15% heat loss
Describe conduction
With direct contact
In humans, 3% heat loss
Describe evaporation
Water from body surface
22% heat loss
How to minimise heat loss through radiation in a cold environ
Decreasing SA:V
Layers of clothing
How to minimise heat loss through convection in a cold environ
Layers of clothing
Sheltered from wind
How to minimise heat loss through evaporation in a cold environ
Little exposed skin
Dry
How to minimise heat loss through respiration in a cold environ
Cover mouth and nose, stops cold air from entering lungs
larger animals have ______ SA:V so lose heat less quickly
smaller
Describe ectotherms
Body temp fluctuates with environ
Temp conformers
Heat is derived from environ
E.g reptiles, amphibians
What are ectotherms also known as
poikilotherms
Give an example of an ecotherm
Reptiles, amphibians