Homeostatic Control in the Body Homeostasis Review Homeostasis
Homeostatic Control in the Body
Homeostasis Review § Homeostasis is how the body keeps conditions inside it the same. § Scientists describe it as the maintenance of a constant internal environment.
Examples § Things that the body keeps the same: – body temperature at 98. 6°F – the amount of water inside our body § Keeping these two the same is not always easy when the outside environment is changing constantly. But it is important so that all our cells function properly. § Strenuous exercise, or living in a hot or cold environment, affect our body temperature and water balance.
How we keep things the same… § First, we need receptors to detect when things such as temperature change. § Then we need a processing center to receive this information and coordinate our response. § Finally, we need effectors to produce a response that ensures our body temperature stays at 98. 6°F.
Web Time § Homeostatic Control System Example
Example: Baby incubator § The incubator needs sensors to monitor the temperature. It also requires a computer or processing centre to monitor and process the data from the sensors and switch the heater on or off. When the incubator is too cold, the heater switches on. When it is too hot, the heater switches off. In this way, it maintains an almost constant temperature within the incubator.
Skin Diagram § Our skin plays an important role in helping us to maintain homeostasis in body temperature. § On the skin diagram, you will need to identify the following items: – hair, sweat glands, temperature receptors, blood vessels, fatty tissue § When you are finished labeling each structure, research and write down the role each plays
Negative Feedback § Negative feedback ensures that, in any control system, changes are reversed and returned back to the set level. § For example, negative feedback keeps our body temperature at a constant 98. 6°F. If we get too hot, blood vessels in our skin vasodilate (become larger) and we lose heat and cool down. If we get too cold blood vessels in our skin vasoconstrict (become smaller), we lose less heat and our body warms up. Negative feedback makes sure this happens.
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