The ability of an organism to sense and react to changes in its body illustrates

Responsiveness

Explanation:

When we talk about responsiveness in biology, we refer to the ability of living things to respond to stimuli, internal or external, or changes in the environment. This response can occur in many ways, such as withdrawal or growth toward this stimulus.

The responsiveness process is not exclusive to animals and is therefore not an exclusive response of the nervous system. Each cell responds differently to a stimulus. In the case of nervous system cells, impulse transmission occurs, a process known as conductivity.