Endocrine: Temperature Flashcards
Core body temperature can change with the ovarian cycle.
Which phase has a lower temp, which has higher?
Lower: Follicular
Higher: Luteal
Body temperature can vary by how many degrees throughout the day?
1-2 C
Heat transfer via electromagnetic radiation. In humans, it is as infrared photons…
This is how most heat is lost with low physical activity
Radiation
Transfer of heat through solid matter…
conduction
transfer of heat through movement of air or liquid across surface…
convection
heat loss via water vaporization…
This is the major mechanism of heat loss on a dry, hot day
evaporation
Eccrine glands have what type of innervation? How may L can be lost on a hot day?
SNS innv.
2-3 L/hr
Passive heat transfer from the core to the skin occurs via what process?
conduction
Active heat transfer from the core to the skin occurs via…
Convection
Heat loss from the surface of the body occurs via which mechanism(s)?
Radiation, Convection, Evaporation
On a hot, dry day, heat loss from the skin occurs mainly via…
evaporation
On a humid day, heat loss is determined by which mechanism almost entirely?
convection
Which thermoreceptor class has a wider range, cold or warm?
cold (24-28 C)
These receptors allow the body to anticipate temperature changes before they are allowed to affect the core temperature
Peripheral thermoreceptors
Warm thermoreceptors are sensitive to what range of temperatures?
44-46
These structures are located in the POA and abdominal organs. They measure core body temperature. How sensitive to temperature are they?
Central thermoreceptors
extremely sensitive to blood temp changes
What part of the hypothalamus integrates thermal information?
POA
Which part of the hypothalamus is responsible for heat dissipation via PNS activity?
anterior hypothalamus
Which part of the hypothalamus is responsible for heat production and conservation via SNS activity?
posterior hypothalamus
What are 4 actions initiated by the posterior hypothalamus in order to produce heat?
increase muscle tone, voluntary actions, shivering, BAT stimulation (infants)
what are 2 actions initiated by the posterior hypothalamus in order to conserve heat?
skin vasoconstriction, postural changes
What are 2 actions initiated by the anterior hypothalamus to decrease heat production?
decrease muscle tone, voluntary actions
What are two actions initiated by the anterior hypothalamus to increase heat loss
skin vasodilation, sweating
What takes precedence over vasodilation when it is hot? Cardiovascular control, or temperature control? What can result due to this?
temperature, BP will drop
