15.2 Thermoregulation in ectotherms Flashcards
1
Q
list ways in which an organism gains heat
A
- waste heat from cell respiration
- conduction from surroundings
- convection from surroundings
- radiation from surroundings
2
Q
list ways in which an organism loses heat
A
- evaporation of water
- conduction to surroundings
- convection to surroundings
- radiation to surroundings
3
Q
define radiation
A
the transmission of electromagnetic waves to and from the air, water or ground
4
Q
define convection
A
the heating and cooling by currents of air or water
5
Q
define conduction
A
heating as a result of the collision of molecules
6
Q
what are ectotherms
A
- organisms that use surroundings to warm their body
- invertebrates: fish, amphibians and reptiles
- if they live in water, they don’t need to thermoregulate
7
Q
what are endotherms
A
- organisms that rely on metabolic processes to warm up
- mammals and birds
8
Q
what behaviours do ectotherms show to raise body temperature
A
- bask in the sun
- orientate bodies so max SA is exposed to the sun
- extend areas of their body to increase SA exposed
- press bodies against the warm ground (through conduction)
- exothermic metabolic reactions
9
Q
what behaviours do ectotherms show to lower body temperature
A
to cool down and prevent enzymes from denaturing, they reverse the warming processes above
10
Q
what are the physiological responses to warming in ectotherms
A
- dark colours to absorb more radiation
- alter heart rate to increase/decrease metabolic rate
