Endotherms and Ectotherms Flashcards
1
Q
What are endotherms?
A
- Organisms that internally control their body temperature by homeostasis e.g mammals, birds
2
Q
What are ectotherms?
A
- Organisms that depend on external sources of heat e.g. reptiles
3
Q
What are the features of endotherms?
A
- control body temperature
- behaviour - dog sticking out tongue
- sweating, cool off in water/shade
- high and constant rate of metabolism
- not dependent on the environment- does not rely on temperature
- high and constant body temperature
4
Q
What are the features of ectotherms?
A
- behaviour e.g basking in sun
- dependent on the environment
- activity depends on the environment- e.g. active when they are warm
- body temperature - variable
5
Q
How do endotherms keep warm?
A
- Nerve impulses from the hypothalamus
- shunt vessels dilate
arterioles become constricted - heat is loss through the skin
6
Q
How do endotherms cool down?
A
- Nerve impulses from the hypothalamus
- shunt vessels constrict
- arterioles dilate
- a lot of heat loss by radiation
7
Q
What is the role of the hypothalamus
A
- the centres gain information from the thermoreceptors
8
Q
What happens if the centre gains heat?
A
- it activates by a drop in temperature
9
Q
What happens if the centre loses heat?
A
- it activates by a rise in temperature
10
Q
What is the structure of the hypothalamus?
A
- two sections for temperature regulation
