The endocrine system works with the to coordinate and regulate the body.

Nervous System.

Explanation:

This is the system concerned with the ability of a human body to respond to stimuli or changes in the environment. It is connected to all parts of the body by nerves, which are made up of thousands of long thin nerve fibres. Example  of how they co-ordinate the body could be seen when a boy runs to catch a ball, he uses hundreds of muscle for the movement and also using information from he sense organs knows the degree of power and correct time to get him to where the ball is.