WHAT IS HOMEOSTASIS?

Homeostasis is the property or ability of a system/body to maintain a relatively constant internal environment despite changes in the external environment. 

The concept was described by French physiologist Claude Bernard in 1865. The word "Homeostasis" was coined by Walter Bradford Cannon in 1926.

Examples:

1. When you move into a cold environment, your muscles contract and cause you to shiver to generate heat. This helps to increase your temperature back to the normal of 98.6 degrees Fahrenheit or 37 degrees Celsius.  
2. When you are hot, you sweat a lot. The sweat takes heat from your body to evaporate. This helps to cool down your body to the normal temperature of 98.6 degrees Fahrenheit or 37 degrees Celsius.  
3. When your blood sugar level goes up, your pancreas produces the hormone, insulin. This causes the sugar to be taken up into the cells. The blood sugar levels then drop to normal.
4. When your blood sugar level drops, you pancreas would release glucagon which stimulates the cells (liver) to release sugar into the blood to increase the level to normal.

How is homeostasis achieved?
There are three main components in the homeostatic control mechanisms for the variable being regulated. 

• Receptor: The receptor is the sensing component that monitors and responds to changes in the environmental variable. 
• Control center: This center receives information from the receptors. It is the component that sets the range at which a variable is maintained. It determines an appropriate response to the stimulus and then sends signals to an effector. The effector can be any structure such as muscles and organs. 
• Effector organ: This is the end organ that brings about the corrective measure after receiving the signal from the control center.  A change occurs to correct the deviation by depressing it with negative feedback.

Here are some video lessons on homeostasis

Video 1

Video 2