My supervisor asked me to write my thesis based upon one paper which I'm co-author on. I was told to take results which were not published and extend the figures. I was also told to include some figures from the paper after I ask the journal for copyright permission, extend the discussion in the paper and insert all of this into my thesis. After all of this, I need to do one more experiment.
Is this usual in science and for a Ph.D.? What precautions should I take in this case?