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

Co-ordination in this sense refers to the regulation or control of body activity. Plants need very little in the way of a control system. Since growth and reproduction are about the only things that are regulated, a rapid control system is not required and hormonal control is all they possess. Animals are continually moving through new environments that may pose all types of changes and threatening situations to the organism. This requires the rapid and precise control of a nervous system. Hormones regulate slower activities, such as growth, development and reproduction.