Thermoregulation (Karius) Flashcards
What parts of the body change temperature the most rapidly?
Feet, then hands, then skin
About how much does the core temperature change throughout the day?
1-2 degrees
Lowest at 6 am
What measures core temperature & the temperature around us?
Thermal Receptors
What are the cutaneous thermoreceptors most sensitive to?
Cold (10x as much as warm)
What information do the visceral thermoreceptors transmit?
Threats from ingested food that may change body temperature => hypothalamus
- Example: ice cream (causes brain freeze which would decrease blood temp. of brain)
Where are the thermoreceptors of the brain located?
Pre-optic and superoptic region of hypothalamus
What are the thermoreceptors in the brain most sensitive to?
Heat (3x as much as cold)
What structure determines the set body temperature, receives info about current temperature and decides what to do?
Hypothalamus
What happens to the core temperature when you sleep and exercise?
- Sleep: T decreases b/c set point decreases
- Exercise: T increases b/c set point increases
What receptors determine the core temperature of the body
Visceral and hypothalamic (preoptic & superoptic) thermal receptors
What does the posterior region of hypothalamus respond to?
Responds to cold by activating heat producing behavior
What does the anterior region of the hypothalamus respond to?
Responds to heat by activating heat loss behaviors
Why do babies need more adipose tissue?
Babies have higher surface area in proportion to size and will lose heat faster than adults
What systems can be used to produce heat
- Autonomic nervous system (esp. sympathetic)
- Endocrine
- Thyroxine
- Epinephrine
- Muscular activity
- Voluntary
- Involuntary (shivering)
- Non-shivering thermogenesis
- increase in metabolism
What part of the hypothalamus is responsible for shivering?
How does it do this?
Dorsomedial posterior hypothalamus => increase motor neuron excitation
You are cold and trying to produce heat