Biological Problems of Death

In some of the recent German reviews this topic has been discussed at some length. Death is called a definite arrest and change of life. This can only occur among multicellular beings, and is not found among unicellular organisms. These latter increase by fusion, growing to a certain stage, then dividing into two parts alike in size and structure. These organisms may be called immortal, because if protected from violent death live on indefinitely. The individuals of these unicellular species on the earth to-day are far older than mankind, and as old as life itself.
Source: JAMA - Category: General Medicine Source Type: research