Ateacher makes the analogy that stem cell research did for medicine what the internet did for communication. what is meant by this analogy?

Internet has changed the nature of communication, making one kind of communication faster, more efficient and more universal (international). However, people find some aspects of Internet as a communication medium controversial, as they say that it stops people from interaction face to face.

Similarly,
Stem cell research has changed the nature of medicine, making one kind of research in medicine faster, more efficient and more powerfull. However, people find some aspects of stem cell research controversial, as they say that involves experimenting with human embryos.

If I were to summarize, I would say that both stem cell research and Internet introduced a step in a new direction, one that is very prolific and will likely develop further.

Hydrosphere is the correct answer