It is clinically used to separate <span>a mixed population of macromolecules such as DNA or proteins in a matrix of </span>agarose<span>, which is one of the two main components of agar.</span>
I found the attached image on the internet related to this question.
The solid arrows represent neuronal communication. The stimulus, the effects, and the flow of information is all done by receptors and synapses that send a signals across the body in order to have effective feedback responses promoting the homeostasis of the organism.
If this is for the scientific process unit, the answer is passing laws to prevent certain types of scientific research. I know because I had this question in biology.
Photosynthesis.. hope I helped (: