Magnesium: Essential for a plant's health, and ours. Magnesium is at the core of the chlorophyll molecule, and an essential ingredient for healthy plants, and the animals (including humans) that eat those plants. All living organisms depend on magnesium in all types of cells, body tissues and organs for a variety of functions.
Some treatment programs will have both counselors and therapists who work with clients. Both provide different levels of intervention with clients. Therapists can provide both group therapy along with one-on-one sessions while counselors may provide psycho-educational groups (but just cannot call it therapy).
Doctor vs Nurse. There has always been a huge difference between a nurse and a doctor. As you might have witnessed yourself, a doctor is the one who does the operations while the nurse is the one who assists him. Hence, what might really be the difference is what they have studied, which is why they reached such professions.