The living organisms are made up of molecules. These are of various sizes, classes, functions, etc. They need to change in some other biomolecules. These conversions are chemical reactions or metabolic reactions.
Metabolism is a defining feature of life, as living things depend on various biochemical reactions. These reactions can be demonstrated outside the body in cell-free systems, which are neither living nor non-living. Isolated metabolic reactions in vitro are thus, not living things, but surely living reactions.
