Body There are many different body systems.
Cells performing similar functions are called a tissue, tissues performing similar functions are called an organ, organs performing similar functions make an organ system, and all the organ systems together constitute the organism. Homeostasis is often accomplished by negative feedback. In a system, negative feedback refers to a portion of the system output being changed in sign, and fed back into the beginning of the system. Thus, the output signal is damped. Your house thermostat, not to mention virtually all electronic circuits use negative feedback to remain stable.