ICPP S1 Thermoregulation And Homeostasis Flashcards
Define homeostasis.
The maintenance of an internal environment, in a constant state, despite external changes.
What are some things that need to be controlled in order to maintain homeostasis?
- Temperature
- pH concentration
- Oxygen concentration
- CO2 concentration
- Electrolyte levels
What are the 3 main components of a homeostatic system?
Receptors.
Control center
Effectors
Define thermoregulation
The control/ maintenance of a constant internal temperature.
Define core temperature.
The temperatures of the internal environment and internal organs.
What are the 2 types of skin themoreceptors?
Skin thermoreceptors and hypothalamic thermoreceptors.
Where do skin thermoreceptors signal?
These sensory receptors send signals to the hypothalamus’ pre-optic area (POA), specifically the thermoregulatory centre in the hypothalamus.
What are the physiological responses to increased core temperature?
Increased cutaneous blood flow - vasodilation.
Increased rate of sweating
Hairs lie flat.
What are the physiological responses to decreased body temperature?
Decreased cutaneous blood flow through vasodilation.
Shivering - skeletal muscle contraction.
Hairs stand on ends.
What is the normal core temperature range?
36.5 to 37.5
As levels of hyperthermia increase at what temperature ranges can we start to classify the following:
- Clinical onset of hyperthermia
- Hyperthermia
- Hyperpyrexia
Clinical onset
37.5-38.3
Hyperthermia
38.3-41
Hyperpyrexia
40-41
As levels of hypothermia decrease at what levels can we classify the following:
- Mild hypothermia
- Moderate hypothermia
- Severe hypothermia
Mild Hypothermia
32-25
Moderated hypothermia
32-28
Severe hypothermia
<28
Why may elderly people have trouble with thermoregulation?
Gradual decline in body function leads to:
- Reduction in function of cardiopulmonary, renal and MSK systems.
- Decreased ability to synthesis NTs - adverse effects on CNS and PNS.
- Decreased sweat response.
Why do neonates and infants have problems with thermoregulation
- Immature body systems
- No thermogenesis shivering reflex
- Limited effects of vasoconstriction
- Excessive sweating will cause fluid loss at higher temperatures.
- Large SA:V - rapid heat loss.
What do neonates and infants rely on for thermoregulation?
Non-shivering thermogenesis.
Large amounts of brown adipose tissue, highly vascular and high rate of metabolism.
Lots of exergonic reactions in the BAT to release high.
