What is the need for a system of control and coordination in an organism?

Explanation

An organism is made up of many tissues, organs and organ system. Each of these is responsible to perform a particular function required for the maintenance of the organism. All these need to be controlled and coordinated for the smooth functioning of the body of the organism.
Any external stimuli received by the body, is processed and appropriate response is initiated. Eg a deer runs [response] on sighting a lion [stimuli].
The control and coordination system helps in:
a] Integrating various metabolic activities
b] Growth of the organisms
c] Responding to an external stimuli in order to protect themselves or the attain nutrition.