Perform an experiment of regeneration on flatworms. Observe the cut ends of the flatworms using the hand lens or the dissection microscope immediately after cutting. What do you see?
Are there distinct differences between the two ends?
Observe the cut ends of the flatworms over a period of several days. Do the flatworm halves continue to exhibit the same degree of difference that was seen right after they were cut in two?

What kinds of changes occur in the flatworms as they recover from having been cut in two?