15.2 Thermoregulation in ectotherms Flashcards
what are the behavioural responses of ectotherms to warm up?
- basking in the sun
- conduction
- exothermic metabolic reactions
how does basking in the sun raise the temperature?
ectotherms orientate their body towards the sun so that the maximum surface area is exposed to the sun
they also extend their bodies to increase surface area
how does conduction raise the temperature?
ectotherms press their body against warm ground and absorbing the heat
how do exothermic metabolic reactions raise the temperature?
ectotherms contract and vibrate muscles to increases cellular respiration which causes the body to heat up
what are the behavioural responses of ectotherms to cool down?
- sheltering in the sun
- reverse conduction
- minimise movement
how does sheltering from the sun reduce the temperature?
ectotherms can seek shade in cracks and by digging burrows which minimises the surface area exposed to the sun
how does reverse conduction reduce the temperature?
ectotherms press their bodies against cool earth or they move into water in order to cool down
how does minimising movement reduce the temperature?
it reduced the metabolic heat generated
what are the physiological responses do ectotherms have?
- their colour
- their heart rate
how do the colours of ectotherms lead to heating up?
they have darker colours which absorb more radiation than lighter colours which means more heat can be absorbed
how does controlling the heart rate lead to ectotherms heating up?
they can alter their heart rate to increase/decrease the metabolic rate
why can ectotherms survive in environments with little food?
they have a low metabolic activity as they need less energy to maintain a constant temperature
