"An isolated metabolic reaction(s) outside the body of an organism, performed in a test tube is neither living nor non-living. Hence, while metabolism is a defining feature of all living organisms without exception, isolated metabolic reactions in vitro are not living things but surely living reactions ". First it is said that they are neither living nor non  living then it is said that they are living reactions. So my question is, are metabolic reactions in vitro living or non living ?

Dear student, 

All living organisms are made up of chemicals. These chemicals can change into different biomolecules through various chemical reactions. The sum total of all chemical reactions occurring in the body of living organisms is known as metabolism. So, all the living organisms whether unicellular or multicellular exhibit metabolism. However, metabolic reactions can also be carried out outside the body in a cell free system. So, the metabolic reactions are living reactions since they are the characteristic feature of living organisms but isolated metabolic reactions carrying out in vitro represent the non-living things.

Regards.