Describe the role of the skin in temperature regulation, with reference to sweating vasoconstriction and vasodilation
Stimulus: Bood temperature (change in internal temperature)
Receptor: Hypothalamus
Effector: Skin
Response: Cooling down/ Warming up
Core temperature is controlled by Hypothalamus. It is a part in the brain that monitors temperature of blood passing through the brain (detects changes in temperature of blood).
It is also responsible for ADH (osmoregulation).
The keeping of inner conditions within acceptable limits, such as water or temperature, is called homeostasis.
Skin is responsible for temperature regulation within our body.
The core temperature of our body is 37 C. It is important to maintain our body temperature at about 37 C because enzyme is most efficient at this temperature.
Temperature control is a negative feedback. This means to any change in the environment, the negative feedback system will try to minimize the change as much as possible.
Blood sugar and water level are also controlled by negative feedback system.
Decreased temperature (too cold) --> trying to warm up
- Vasoconstriction - capillaries narrows, so they carry less blood. This keeps heat inside the body
- Reduce sweating
- Hair erection (goose bumps) - muscles contract to makes hair stand up in order to trap the layer of air to avoid heat from escaping (it is a poor conductor of heat)
- Shivering - releases extra heat from increased respiration
- Insulation from a layer of fat under the skin
Increased temperature (too hot) --> trying to cool down
- Vasodilation - Capillaries widened so more blood can be carried to the surface. heat transferred out of the body through conduction and radiation.
- Sweating occurs for evaporation as it reduces amount of heat.
- Hairs lay flat = less air is trapped so heat can transfer out of surroundings
- No shivering occurs.
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