Lecture 3: Thermoregulation 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?
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
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?
Hypothalamus
What happens to the core temperature when you sleep and exercise?
- Sleep: set point decreases
- Exercise: set point icnreases
What does the posterior region of hypothalamus respond to?
Responds to cold by producing heat
What does the anterior region of the hypothalamus respond to?
Responds to heat by lowering heat
Why do babies need more adipose tissue?
Babies have higher surface area in proportion to size and will lose heat faster than adults
What part of the hypothalamus is responsible for shivering?
Dorsomedial posterior hypothalamus => increase motor neuron excitation
You are cold and trying to produce heat
What division of the autonomic nervous system is involved in heat production?
Sympathetic Nervous System
In non-shivering thermogenesis, what hormone is released in response to cold?
Thyroxin-Releasing hormone => Thyroxin
Epinephrine
