Answer:
free radical
Step-by-step explanation:
The most scientifically accepted free radical theory of aging is the theory of free radical aging, which proposes that reactions triggered by free radicals are responsible for the molecular damage underlying the aging process. From this perspective, aging would ultimately be the result of a generalized cellular oxidation process; This is why it is often said that "man does not grow old but oxidizes." That is, according to this theory, unstable oxygen molecules cause damage to the structure of cells, ie oxidizing, increasing with age.