This is How our body is defined by Modern medicine or Western Medicine- Allopathy.
But if you see or define our body from Indian books of Ayurveda and particularly according to Upanishadas text (Taitreya Upnishad) point of view –
We are not only physical body but We are composition of 5 koshas.
These Panch Koshas are forming our body and existence and are being controlled by 4 ANTAR MOUNAS
1. Maan– Center of Emotions origin is Mind
2. Budhhi– Center of Intelligence origin is Brain
3. Chitta– Center for Realization of Truth origin is Consciousness.
4. Ahankar– Comes from Body and Energy which is perceived as Ego.
For many centuries or Decades We have been drifted away from originality of our HINDU scriptures which are written in Sanskrit. Now in present era we all have entered in Global culture understanding. Means we understand only things written or printed in English. This is Understandable as we were slaves for 200 and odd years.