As a veterinarian, I wear a number of different hats:
1. Physician; I diagnose and treat illness
2. Surgeon; I physically remove disease, repair fractures etc
3. Anaesthetist
4. Pathologist
etc etc
You get the idea.
The science at the base of all that I do is biology. So, as a veterinarian, I am perhaps best regarded as being something of a specialised biologist.
But what IS biology? When we get down to the question of what actually makes biology tick, it is the chemistry of life, or biochemistry. That anaesthetic drug I inject works because it blocks various receptors in the brain. My patient gets sick because the virus in its gut caused abnormal biochemical reactions to occur leading to vomiting, diarrhoea, loss of vrious electrolytes which in turn has other effects in other parts of my patient's body.
So it appears that biology comes down to being the result of a massive complex of chemical reactions that come together to prodcue life and all that goes with life.
So perhaps I am a biochemist.
But then again, what is chemistry? What is it that makes all of those chemical reactions occur, whether that be occurring in the body of my patient or in a beaker of acid to which I have placed a piece of metal (not because that has anything to do with biology, but just because I wanted to see what happened)? Why does one atom of this react with 2 atoms of that? why does one sodium ion like to get together with one chloride ion to produce table salt? What makes the NaCl molecule stay together as a molecule and not fly off as two separate ions? Or why does it fly off as two separate ions?
Physics! The electromagnetic force between the two ions, the strong and weak nuclear forces. As for gravity, I'm nt sure how much of a role that has to play in biology. But the thing is that it's physics that makes the chemistry happen which makes the life happen which gives me a patient to treat.
As far as I can tell the maths comes in as a way of describing the physics, it's the story (equation) of how and why the physics works the way that it does. But then, what would I know, I'm just a vet!
So, in reply to Zaps comment of "maths is everything and everything is maths", I have been known to say the same thing about physics. Not going to argue about which, if either, of those statements is correct.
Stuart