Regulation Of Body Temp 🥶🥵 Flashcards
Which part of the brain control temp?
Thermoregulatory centre in the hypothalamus
How the negative feedback work in control of body temp?
Body temperature lower than normal is detected by thermoreceptors in hypothalamus and skin.
Thermoreceptors send nerve impulses to heat gain centre.
The heat gain centre sends nerve impulses to effectors to reduce heat loss and increase heat gain until normal body temperature is restored.
Regulation of body temperature by skin under cold conditions
Sweating decrease
Arterioles constrict (vasoconstriction). Less blood flows through the capillaries near to skin surface.
Erector muscle contract to pull hair upright so a thicker layer of still air is trapped for better insulation of heat.
More blood flows to the subcutaneous fat and becomes thicker (long-term response)
Name the action of contraction of muscle to regulate body temp
Shivering
-short-term response
-involuntary
-uncoordinated
-rate of respiration in muscle cells increased
Name the hormone that regulate body temp
Thyroxine secreted by thyroid gland
-increase metabolic rate of body cells
Why use aluminium foil to cover body and drink hot chocolate under cold condition?
Aluminium foil use of radiation to trap heat and reduce heat loss
Sugar in hot chocolate can increase respiration to generate more heat
Why high relative humidity under hot condition is bad?
Sweat evaporation will be hindered so heat cannot be lost effectively
How high air temp hinder heat loss?
Gradient between body temperature and air temperature is narrower
Heat loss through conduction, convection and radiation is less effective
Name two heat-related illness
Heatstroke and heat exhaustion
Name a cold related illness
Hypothermia
