Two men are looking through microscopes in a room.
There are biologists checking for tissue abnormalities.
It is not necessarily true that they are biologists.
WE have no idea if they are biologist, they could be anyone. We have no idea if they are looking at tissue abnormalities, they could be looking at anything.
Not all people that look through microscopes are biologists. Not all people that look through microscopes are looking for tissue abnormalities.