section 1. (8) compare responses of named Australian ectothermic and endothermic organisms to changes in the ambient temperature and explain how these responses assist temperature regulation Flashcards
1
Q
What is an ectotherm?
A
- an organism that changes its body temperature with heat from the environment
- have limited ability to control body temp
2
Q
What are the responses of a blue-tongued lizard to warm and cool conditions?
A
- ectotherm
- cool conditions: flattens body to increase exposed SA to the sun, hibernates in a sheltered spot to reduce metabolism
- warm conditions: seeks shade, reduces activity, goes to a burrow
3
Q
What are the responses of a brown snake to warm and cool conditions?
A
- ectotherm
- cool conditions: basks in the sun, uses fat reserves, slows down metabolism, hibernates
- warm conditions: seeks shade, reduces activity, goes to a burrow
4
Q
What are the responses of magnetic termites to warm and cool conditions?
A
- ectotherm
- packs walls of mounds with insulating wood pulp
- aligns mound north-south, hence maximising in the evenings and mornings when it is cooler and minimising during the warmest part of the day.
5
Q
What is an endotherm?
A
- an organism that maintains a constant body temperature despite fluctuations in ambient temperature
- rely on internal sources for heat energy (i.e: metabolism)
- most maintain a temp higher than that of their surroundings
6
Q
What is a response of a red kangaroo to hot conditions?
A
- in hot conditions will lick forearms, where the skin is thinner and blood supply is closer to the skin
- evaporation from saliva causes the temperature of blood to fall
7
Q
what is the response of the fairy penguin to hot and cold conditions?
A
- has feathers that trap a layer of air close to the skin, reducing the amount of heat loss and providing insulation
- in hot conditions: feathers lie flat, trap less air, penguin moves into the water to cool down
- in cool conditions: feathers puff up to trap more air, huddles close to other penguins
