(a) The sum total of all the chemical reactions occurring in the body is known as metabolism and no non-living object exhibits metabolism.
(b) However, metabolic reactions can be demonstrated outside the body in a test tube (cell free medium).
(c) Thus, isolated metabolic reaction (s) outside the body of an organism, performed in a test tube is neither living nor non-living.
(d) Metabolic reactions occurring in vitro are living reactions but not living things.