Do you consider a person in coma-living or dead?
Consciousness is a defining property of all living organisms. Whereas, coma is a profound or deep state of unconsciousness lasting more than six hours, in which a person can not be awakened and fails to respond normally to external stimuli, light or sound.
Such a person exhibits a complete absence of wakefulness and is unable to consciously feel, speak, hear or move. Such a person is called brain dead but as the body system is functioning, the person is considered as living.