Homeostasis is defined as a state in which the conditions of an organism's internal environment are maintained within tolerable limits. what mechanisms in your body are involved with homeostasis?

There are many cases of homeostasis mechanism. In this mechanism, there will be a receptor that will catch a condition. After that, an order will be sent to various place depend on the condition.
One of them is temperature control which was done by shivering or sweating. When your body temperature is too high, the thermoreceptor will detect it and then the brain will send the order to the body sweat glands. Sweat on body surface will evaporate and reduce body temperature.
When the temperature is too low, the brain will tell the muscle to shiver so you can produce heat.

Other than temperature, homeostasis also control blood pressure, or many chemical level(oxygen, glucose).