Who am I?

Who am "I"?
I am Chandra... I am Engineer... I am Human... I am Animal... I am Life... I am x... I am y...
I am my Body... I am my Brain... I am my Mind...
I am my Soul... I am God...

There are so many Chandras, so many Engineers, so many Humans... so many so many.... they are not "I"...
So who am I? Am I my Body? Am I my Brain?

Well... lets see...
Body = Integration of Body parts, which makes me... individual body parts are part of me... none of them individually is me... body parts can be replaced... robotic hand for example... hands, legs, eyes, ears, heart, kidney, lungs etc are being replaced with artificial parts or parts from other humans/animals... most of the parts in our stomach are for digesting food and generating and distributing energy... energy used by our hands to do work... our legs to take us around... our senses to sense external world... these sensors (eyes, ears etc) can be replaced with artificial sensors, energy for them can be supplied with batteries...
So, what is remaining? Brain. Brain "thinks" I have to go there - legs will take us there. Brain thinks I have to do this - hands will do that... etc.

Also, our body is a small world to many bacterias and their colonies... only 10% of our cells are ours... "Human beings are not really individuals; they're communities of organisms".
http://science.slashdot.org/article.pl?sid=09/04/15/0252219

So, am I simply my "Brain"?

What is Brain? A very complex organ, which gathers information from sensors, stores that information, processes that information... triggers actions...
All these can be done an "Artificial Brain" (Machine + Artificial Intelligence) which can gather information, store, process... Am I replaceable with "Artificial Brain"? "I" hope not.

Am I my "Mind"?

Emotions/feelings/love/anger/happiness/hate/greed... are these simply chemical reactions? Can we attribute them to Mind? Is it my "Mind" triggering these in "Brain"... then I am not my "Brain"... I am my "Mind"... my Mind can control an "Artificial Brain" which can gather information, store, process... trigger actions...
Who triggers Emotions/feelings in my Mind? Other Minds. I see so much of this in this world.

So far the discussion is Materialistic... Practical... The border case between Brain and Mind...
Now, it takes new way of thinking...

Is the following maturity level order holds good?
Body -> Brain -> Mind -> Soul -> God.

"I" do not know.